The technique used to produce a 3D tissue engineering (TE) scaffold is of fundamental importance in order to guarantee its proper morphological characteristics. An accurate assessment of the resulting structural properties is therefore crucial in order to evaluate the effectiveness of the produced scaffold. Synchrotron radiation (SR) computed microtomography (m-CT) combined with further image analysis seems to be one of the most effective techniques to this aim. However, a quantitative assessment of the morphological parameters directly from the reconstructed images is a non trivial task. This study considers two different poly(e-caprolactone) (PCL) scaffolds fabricated with a conventional technique (Solvent Casting Particulate Leaching, SCPL) and an additive manufacturing (AM) technique (BioCell Printing), respectively. With the first technique it is possible to produce scaffolds with random, non-regular, rounded pore geometry. The AM technique instead is able to produce scaffolds with square-shaped interconnected pores of regular dimension. Therefore, the final morphology of the AM scaffolds can be predicted and the resulting model can be used for the validation of the applied imaging and image analysis protocols. It is here reported a SR m-CT image analysis approach that is able to effectively and accurately reveal the differences in the pore- and throat-size distributions as well as connectivity of both AM and SCPL scaffolds.

Two different dielectric barrier discharge processes are presented, fed with the aerosol of the organic precursor, to deposit -CHO containing coatings from lactic acid (pdLA) and tetraethylene glycol dimethyl ether (PEO-like) of possible interest in biomedical applications as biodegradable and non-fouling polymers, respectively.

Scaffold design is a key factor in the clinical success of bone tissue engineering grafts. To date, no existing single biomaterial used in bone repair and regeneration fulfils all the requirements for an ideal bone graft. In this study hydroxyapatite/polycaprolactone (HA/PCL) composite scaffolds were prepared by a wet chemical method at room temperature. The physico-chemical properties of the composite materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, while scaffold morphology was investigated by scanning electron microscopy (SEM) with energy-dispersive spectroscopy to validate the process used for synthesis. Finally, the response of bone marrow-derived human mesenchymal stem cells (hMSCs) in terms of cell proliferation and differentiation to the osteoblastic phenotype was evaluated using the Alamar blue assay, SEM and alkaline phosphatase activity. Microstructural analysis indicated that the HA particles were distributed homogeneously within the PCL matrix. The biological results revealed that the HA/PCL composite scaffolds are suitable for the proliferation and differentiation of MSCs in vitro, supporting osteogenesis after 15 days. All the results indicate that these scaffolds meet the requirements of materials for bone tissue engineering and could be used for many clinical applications in orthopaedic and maxillofacial surgery.

Bovine lactoferrin and lactoferricin B, well-known for their antimicrobial properties, were individually immobilized on two different coatings functionalized with − COOH groups deposited in the inner part of polyethylene micro tubes by means of a plasma deposition (PE-CVD) process fed with ethylene and acrylic acid vapors. The resulting functionalized tubes were tested for antimicrobial activity against three Pseudomonas strains responsible for casein hydrolysis and cheese pigmentation. The cell counts of these spoilage bacteria, incubated for 30 h under their optimal growth conditions, were found to be significantly reduced after 24 h in micro tubes functionalized with lactoferricin B, whereas a very low antimicrobial activity against the same strains, often undistinguishable from that of control samples, was observed in tubes functionalized with lactoferrin. This is the first work in which a plasma coating functionalized by lactoferricin B was studied to make an active packaging useful to control cheese spoilage by Pseudomonas. Industrial relevance The current study describes a new method to immobilize two food grade proteinaceous natural compounds. The resulting plasma-functionalized lactoferricin B-immobilized coating is a promising tool for the control of spoilage microorganisms and shelf-life extension of cheeses. Abbreviations PE-CVD, plasma enhanced-chemical vapor deposition; BLF, bovine Lactoferrin; LfcinB, Lactoferricin B; HM, Mozzarella cheese High Moisture Mozzarella cheese; pdEthAA, plasma deposited Ethylene/Acrylic Acid; XPS, X-ray Photoelectron Spectroscopy; IEX, ion-exchange chromatography; LOQ, limit of quantification; EDC, 1-Ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride; PBS, phosphate buffered saline; PP, polypropylene; PCB, Plate Count Broth; PCA, Plate Count Agar; II, Inhibition Index; GLM, General Linear Model; ANOVA, Analysis of variance; LSD, Fisher's least significant difference; P, statistical probability; LC/MS, Liquid chromatography–mass spectrometry; HPLC, High-performance liquid chromatography Keywords Antimicrobial peptides; Plasma processing; Active packaging; Food spoilage; HM Mozzarella cheese -------------------------------------------------------------------------------- 1. Introduction Antimicrobial peptides (< 10 kDa; 3–50 amino acid residues) have been extensively investigated for promising applications in food preservation (Meng, Huanli, & Fengshan, 2010). Among milk proteins, bovine lactoferrin (BLF) has gained much interest as functional bioactive ingredient for applications in food, personal care, pharmaceutical products (Wakabayashi, Yamauchi, & Takase, 2006) and for its antimicrobial activity against fungi, yeasts and Gram-negative and positive bacteria (Naidu, 2000). Some authors have demonstrated that the digestion of BLF with pepsin releases the peptide lactoferricin B (LfcinB), largely responsible for BLF antibacterial activity (Bellamy et al., 1992 and Tomita et al., 1991). Active packaging systems can be categorized into adsorbing (e.g. oxygen and ethylene scavengers) and releasing systems (e.g. flavor and odor releasers and antimicrobials), as recently reviewed (Pereira de Abreu, Cruz, & Paseiro Losada, 2012). Concerning antimicrobial releasing systems, most researches were addressed to control pathogens in foods such as Listeria monocytogenes ( Cha et al., 2003, dos Santos Pires et al., 2008, Limjaroen et al., 2005, Nguyen et al., 2008, Santiago-Silva et al., 2009 and Trinetta et al., 2010), whereas fewer studies have concerned with antimicrobial packaging for the control of spoilage bacteria. Appendini and Hotchkiss (2001) found that a 14-amino-acid residue peptide, covalently immobilized on polystyrene by solid phase peptide synthesis, was microcidal in a concentration and time dependent manner against several microorganisms re-suspe

In this work, the response of Saos2 cells to polymeric Surfaces with different toughness/density Of nanometric dots produced by a tailored plasma-etching process has been studied. Topographical features have been evaluated by atomic force microscopy, while wetting behavior, in terms of water-surface adhesion energy, has been evaluated by measurements of drop sliding angle. Saos2 cytocompatibility has been investigated by scanning electron microscopy, fluor. escent macroscopy, and optical, microscopy. The similarity in outer chemical composition has allowed isolation of the impact of the topographical features on cellular behavior. The results indicate that Saos2 cells respond differently to surfaces with different nanoscale topographical - features, clearly showing a certain inhibition in cell adhesion when the nanoscale is particularly small. This effect appears to be attenuated in surfaces with relatively bigger nanofeatures, though these express a more pronounced slippery/dry wetting character.

Synthetic biodegradable polymers are commonly used as scaffolds for tissue engineering despite their poor cell adhesion compared to natural polymers. One of the problems in using biodegradable scaffolds is that a higher cell colonization at the scaffold periphery and inadequate colonization at its center is generally noted. Such aspects could seriously compromise the in vivo regeneration of a damaged tissue and, in turn, the success of the implant. Plasma processes have been lately proven as promising scaffold modification techniques. The current work aims at enhancing cell colonization in the core of polymer scaffolds via plasma deposition of coatings with different chemical characteristics. The versatility and ability of plasma processes to modify only the outermost layer of a material can render them competitive with respect to wet chemistry approaches in the field of biomedical materials. In this paper some of the results obtained by plasma processing of 3D interconnected porous polymer scaffolds for Tissue Engineering will be shown. In particular, it will be shown how it is possible to enhance cell adhesion, growth and colonization in porous Polycaprolactone (PCL) scaffolds where gradient of surface compositions are induced from the external (e.g., hydrophobic, slightly cell-repulsive) to the internal (e.g., hydrophilic, cell-adhesive) side of the scaffolds. 3D scaffolds were modified with several RF (13.56 MHz) deposition and treatment plasma processes. Materials were characterized by means of XPS, and FT-IR techniques. Cell-growth experiments were run with cell-lines to check the efficiency of several treatments to enhance/accelerate cell in-growth inside scaffolds.

A method was developed to functionalize biomedical metals with liposomes. The novelty of the method includes the plasma-functionalization of the metal surface with proper chemical groups to be used as anchor sites for the covalent immobilization of the liposomes. Stainless steel (SS-316) disks were processed in radiofrequency glow discharges fed with vapors of acrylic acid to coat them with thin adherent films characterized by surface carboxylic groups, where liposomes were covalently bound through the formation of amide bonds. For this, liposomes decorated with polyethylene glycol molecules bearing terminal amine-groups were prepared. After ensuring that the liposomes remain intact, under the conditions applying for immobilization; different attachment conditions were evaluated (incubation time, concentration of liposome dispersion) for optimization of the technique. Immobilization of calcein-entrapping liposomes was evaluated by monitoring the percent of calcein attached on the surfaces. Best results were obtained when liposome dispersions with 5 mg/ml (liposomal lipid) concentration were incubated on each disk for 24 h at 37 degrees C. The method is proposed for developing drug-eluting biomedical materials or devices by using liposomes that have appropriate membrane compositions and are loaded with drugs or other bioactive agents.

Electrolyte-gated organic field-effect transistors are successfully used as biosensors to detect binding events occurring at distances from the transistor electronic channel that are much larger than the Debye length in highly concentrated solutions. The sensing mechanism is mainly capacitive and is due to the formation of Donnan's equilibria within the protein layer, leading to an extra capacitance (CDON) in series to the gating system.

Little is known about how cells respond to different biomaterials at the molecular level. Biomaterials could stimulate specific cellular responses at the molecular level, such as activation of signalling pathways that control gene activity involved in the maintenance, growth and functional regeneration of liver tissue in vitro. This aspect is an important step in liver tissue engineering. Currently, there are no data available concerning the modulation of cellular genomic response by using synthetic membranes in a bioartificial system. For the first time we investigated gene expression profiles of primary hepatocytes cultured on different substrates: collagen sandwich, native and NH3 plasma-grafted PEEKWCPU membranes. Gene expression in cell suspension prepared after cell isolation was used as a control. Generally, microarray data revealed that the expression of the majority of genes remained unchanged compared to the control. Among 31 000 genes, 52 were significantly changed: 20 were upregulated and 32 downregulated. There were similar changes in gene expression of hepatocytes cultured in the membranes and collagen sandwich. However, some genes involved in the cell proliferation and functional metabolic pathways are more expressed in cells cultured on the membranes and especially on the functionalized ones. Both membranes sustained liver functions at the molecular level, demonstrating their suitability for the reconstruction of liver and as a toxicogenomic tool to predict the liver response to novel drugs.

There is an increasing interest in low cost, timesaving, yet reliable, point-of-care assays. Direct electronic, label-free transduction of bio-recognition events represents a compelling alternative offering miniaturization, easy data handling and processing. Low costs and versatility can be provided if organic electronic devices such as organic fi eld-effect transistors (OFETs) are used as transducers. [ 1 , 2 ] At the beginning, OFET sensors were mostly involved the detection of volatile chemical analytes, [ 3 , 4 ] while organic electronics allowed fabrication of sensing circuits on fl exible substrates. [ 5 , 6 ] However, bare OFET-sensor responses are based on weak interactions that are non-specifi c in nature. Specifi city can be achieved by endowing the OFET with receptor molecules capable of selectively interacting with given analytes.

In this work a genuine combination of a bottom-up approach, which is based on synthesis and functionalization of emitting nanocrystals (NCs), with a top-down strategy, which relies on a flexible and versatile cold plasma process, is shown. Luminescent semiconducting colloidal NCs consisting of a CdSe core coated with a ZnS shell (CdSe@ZnS) are directly assembled onto micro-patterned substrates previously functionalized by means of glow discharges performed through physical masks. The NC assembly is driven by electrostatic interactions that led to their successful organization into spatially resolved domains. Two distinct protocols are tested, the former using a plasma deposition process combined with an electrostatic layer-by-layer procedure, the latter based on a two-step plasma deposition/treatment process. The procedures are thoroughly monitored with fluorescence microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy and scanning electron microscopy. The two-step plasma protocol is demonstrated to be more efficient in directing a uniform and specific assembly of luminescent NCs with respect to the hybrid procedure. The presented 'mix and match' approach offers great potential for integrating NCs, with their unique size-dependent properties, into microstructures, providing a universal platform for the fabrication of sensors, biochips, displays and switches.

In this work a genuine combination of a bottom-up approach, which is based on synthesis and functionalization of emitting nanocrystals (NCs), with a top-down strategy, which relies on a flexible and versatile cold plasma process, is shown. Luminescent semiconducting colloidal NCs consisting of a CdSe core coated with a ZnS shell (CdSe@ZnS) are directly assembled onto micro-patterned substrates previously functionalized by means of glow discharges performed through physical masks. The NC assembly is driven by electrostatic interactions that led to their successful organization into spatially resolved domains. Two distinct protocols are tested, the former using a plasma deposition process combined with an electrostatic layer-by-layer procedure, the latter based on a two-step plasma deposition/treatment process. The procedures are thoroughly monitored with fluorescence microscopy, atomic force microscopy, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy and scanning electron microscopy. The two-step plasma protocol is demonstrated to be more efficient in directing a uniform and specific assembly of luminescent NCs with respect to the hybrid procedure. The presented ‘mix and match’ approach offers great potential for integrating NCs, with their unique size-dependent properties, into microstructures, providing a universal platform for the fabrication of sensors, biochips, displays and switches.

Stainless steel surfaces were processed by means of plasma enhanced chemical vapor deposition (PE-CVD) fed with acrylic acid vapors in order to functionalize them with carboxyl groups, which were subsequently activated for covalent immobilization of heparin-loaded (HEP) NH2 group-functionalized (Fun) nanoliposomes (NLs). Empty Fun or HEP non-functionalized (control) NLs were used as controls. NLs were characterized for mean diameter, surface charge and heparin encapsulation/release. Different lipid compositions were used for NL construction; PC/Chol (2:1 mol/mol) or PC/Chol (4:1 mol/mol) (fluid type vesicles) [ which allow gradual release of heparin] and DSPC/Chol (2:1 mol/mol) (rigid type vesicles). Surface haemocompatibility was tested by measuring blood clotting time. Platelet adhesion on surfaces was evaluated morphologically by SEM and CLSM. The haemocompatibility of plasma-processed surfaces was improved (compared to untreated surfaces); Fun-HEP NL-coated surfaces demonstrated highest coagulation times. For short surface/blood incubation periods, surfaces coated with Fun-HEP NLs consisting of PC/Chol (2:1) had higher coagulation times (compared to DSPC/Chol NLs) due to faster release of heparin. Heparin release rate from the various NL types and surface platelet adhesion results were in agreement with the corresponding blood coagulation times. Concluding, covalent immobilization of drug entrapping NLs on plasma processed surfaces is a potential method for preparation of controlled-rate drug-eluting metallic stents or devices.

Cellular adhesion and proliferation inside three-dimensional synthetic scaffolds represent a major challenge in tissue engineering. Besides the surface chemistry of the polymers, it is well recognized that scaffold internal architecture, namely pore size/shape and interconnectivity, has a strong effect on the biological response of cells. This study reports for the first time how polycaprolactone (PCL) scaffolds with controlled micro-architecture can be effectively produced via bioextrusion and used to enhance the penetration of plasma deposited species. Low-pressure nitrogen-based coatings were employed to augment cell adhesion and proliferation without altering the mechanical properties of the structures. X-ray photoelectron spectroscopy carried out on different sections of the scaffolds indicates a uniform distribution of nitrogen-containing groups throughout the entire porous structure. In vitro biological assays confirm that plasma deposition sensitively promotes the activity of Saos-2 osteoblast cells, leading to a homogeneous colonization of the PCL scaffolds.

Atmospheric pressure(AP)DielectricBarrierDischarges(DBD)generatedinairwereperformedonwater, Phosphate BufferSaline(PBS)andDulbecco'sModified Eagle'sMedium(DMEM)inordertoevaluate their potentialtogeneratehydrogenperoxide(H2O2), nitrite(NO2 − ) andnitrate(NO3 − ) species.Differences in cellgrowthandmorphologywerefoundintwodifferenttypesofeukaryoticcells,immortalandstem cells, incubatedfor1hinplasmatreatedDMEM,revealingaselectivityofthetreatment.

The electrical transport across a biomimetic interface made up of spin coated melanin layers on nanotextured silicon surfaces with different texturing features and wetting properties is discussed. Nanotexturing allows, under certain conditions, the melanin better anchoring on a hydrophobic silicon surface, overcoming the hydrophilic melanin-hydrophobic silicon interface criticism. The feature of the electrical signal transduction across such a structure was studied by impedance spectroscopy and found to be influenced by the nano-texturing chemistry and surface morphology. The effects of a voltage pulse, as external stimulus modifying the electrical transport mechanisms and retention of the subsequently achieved carrier transport conditions have been elucidated. The results let to foresee a possible exploiting of this circuital element for bio and environmental molecules sensing.

We describe the tailoring of polymer surfaces with CFx composition and roughness/density of different micro-/nanometric relieves (ribbons, petals, domes, dots) tuned independently in low pressure plasma deposition and etching processes. Similarity of outer chemical composition grants the comparison of cell culture results to analyze the impact of topographical features on cellular behavior. Such surfaces are of interest for biomedical substrates since tuning their surface composition and morphology can drive the behavior of cells in contact with them.

Background: Isolated hepatocytes removed from their microenvironment soon lose their hepatospecific functions when cultured. Normally hepatocytes are commonly maintained under limited culture medium supply as well as scaffold thickness. Thus, the cells are forced into metabolic stress that degenerate liver specific functions. This study aims to improve hepatospecific activity by creating a platform based on classical collagen sandwich cultures. Results: The modified sandwich cultures replace collagen with self-assembling peptide, RAD16-I, combined with functional peptide motifs such as the integrin-binding sequence RGD and the laminin receptor binding sequence YIG to create a cell-instructive scaffold. In this work, we show that a plasma-deposited coating can be used to obtain a peptide layer thickness in the nanometric range, which in combination with the incorporation of functional peptide motifs have a positive effect on the expression of adult hepatocyte markers including albumin, CYP3A2 and HNF4-alpha. Conclusions: This study demonstrates the capacity of sandwich cultures with modified instructive self-assembling peptides to promote cell-matrix interaction and the importance of thinner scaffold layers to overcome mass transfer problems. We believe that this bioengineered platform improves the existing hepatocyte culture methods to be used for predictive toxicology and eventually for hepatic assist technologies and future artificial organs.

The behavior of cells in terms of cell-substrate and cell-cell interaction is dramatically affected by topographical characteristics as shape, height, and distance, encountered in their physiological environment. The combination of chemistry and topography of a biomaterial surface influences in turns, important biological responses as inflammatory events at tissue-implant interface, angiogenesis, and differentiation of cells. By disentangling the effect of material chemistry from the topographical one, the possibility of controlling the cell behavior can be provided. In this paper, surfaces with different roughness and morphology were produced by radiofrequency (RF, 13.56 MHz) glow discharges, fed with hexafluoropropylene oxide (C3F6O), in a single process. Coatings with different micro/nanopatterns and the same uppermost chemical composition were produced by combining two plasma deposition processes, with C3F6O and tetrafluoroethylene (C2F4), respectively. The behavior of osteoblastlike cells toward these substrates clearly shows a strict dependence of cell adhesion and proliferation on surface roughness and morphology.

A plasma enhanced chemical vapor deposition process was proposed to functionalize the P3HT organic semiconductor surface of electrolyte gated organic field effect transistors with hydrophilic coatings bearing –COOH groups. Results demonstrate that the developed plasma process allows to functionalize the P3HT surfaces with carboxyl groups with negligible adverse effect on the bulk properties of P3HT as well as on EGOFET performances.

Poly epsilon-caprolactone (PCL) and poly (DL)-lactic acid (P(D,L)LA) scaffolds with controlled pore dimensions (100-200 mu m) were processed in low pressure RF (13.56 MHz) Glow Discharges. Ethylene/N(2) mixtures (for PCL) and allyl amine (for P(D,L)LA) were used to plasma deposit cell-adhesive coatings with controlled conditions to increase the affinity of Saos2 osteoblast and 3T3 fibroblast cell lines, respectively. Very promising results were obtained in terms of N-containing species penetration, by plasma processes, inside the core regions of scaffolds. In particular, a new double deposition process from allyl amine (core) and hexane (periphery), created a chemical gradient from the top to the bottom of the scaffolds, that increased the metabolic activity of cells inside the scaffolds.

In this paper, we describe the deposition of PEO-like coatings using dielectric barrier discharges (DBDs) fed with aerosols of the TEGDME organic precursor in helium. By properly tuning plasma parameters such as aerosol/carrier flow ratio, frequency of the electric field applied and input power, the deposition process could be modulated to obtain coatings with variable PEO character, from 50% (cell adhesive) to 70% (nonfouling), which are interesting for surface modification of biomaterials and biomedical devices.

Herein, plasma deposited thermally responsive thin polymer films from N-vinylcaprolactam (NVCL) is reported for the first time by using a low pressure RF plasma process. While FT-IR and XPS analyses highlight the film chemistry, ToF-SIMS combined with MALDI-MS analyses allow to accurately identify different oligomer distributions in the deposited film. The switching behavior of these smart surfaces is confirmed with water contact angle measurements at low and high temperatures, allowing also to estimate the Lower Critical Solution Temperature

In this study, polyvinyl alcohol films incorporated with lysozyme, as active compound, and natural fibres were investigated. Various composite systems were developed to control the release of lysozyme from the matrix by using different surface treatments of the natural fibres. Specifically, the plasma enhanced-chemical vapour deposition of acrylic acid and diamond-like coating on spelt bran powders, in a particular home-made rotating plasma reactor, were studied. Moreover, a mathematical model able to describe the release kinetics of the active compound from the polyvinyl alcohol film into water was presented. To validate the model the release kinetic of lysozyme were determined. The model was successfully used to fit the above experimental data, corroborating the validity of the hypothesis made to derive it. Results showed that the incorporation of treated natural fibres to the polymeric matrix allows to obtaining a decrease of the lysozyme diffusion coefficient up to 73.5% compared to active film without fibre.

Cold plasmas are continuously developed for biomaterials engineering as well as for therapeutic treatments of cells and tissues. For this last application plasma activated media (PAM) and reactive oxygen and nitrogen species (RONS) gained attention as key players. Here, the use of cold atmospheric pressure (AP) plasma is described, for generating RONS in Dulbecco's Modified Eagles Medium (DMEM); superoxide anion (O2-), hydrogen peroxide (H2O2), nitrates (NO3-), and nitrites (NO2-) were detected. PAM was applied to Bone Marrow Stem Cells (BMSC) and SAOS-2 osteoblasts. Both native and plasma-modified polymeric scaffolds were used as three dimensional (3D) supports for cell cultures. The cell activity was found dependent on both PAM and cell type. BMSCs grown on plasma-coated scaffolds tolerated better PAM with respect to those on native scaffolds

Surface modification techniques based on plasma processes allow to tune surface composition, morphology and properties of materials in several applications. This short review is aimed to list, according to the knowledge of the author, established and recently reported plasma deposition processes of “teflon-like” and PEO-like coatings to be used, in biomedical applications, to tailor at the best surface composition and morphology of biomaterials and biomedical devices to drive the interactions of proteins, cells, bacteria and biological tissues in contact with them.

Procedimento per la realizzazione, o il ripristino, per via plasmochimica di un film (film barriera, eventualmente multistrato, che consente di effettuare in modo controllato, uniforme e duraturo il rilascio di sostanze di interesse da un substrato che include come micro/nano particelle la sostanza da rilasciare, oppure da uno strato depositato sul substrato che include come micro/nano particelle la sostanza da rilasciare, oppure da uno strato di sostanza da rilasciare depositata sul substrato, oppure da un substrato che è la sostanza da rilasciare eventualmente in forma di particelle, in cui la sostanza da rilasciare è scelta dal gruppo comprendente metalli e composti con proprietà antibatteriche e molecole biologicamente attive, quali farmaci, ormoni, estratti vegetali, oligopeptidi, lipidi, protidi e glicidi; lo strato con la sostanza da rilasciare (matrice) è ottenuto dal deposito di uno strato, inorganico o organico, eventualmente con struttura simile ai polimeri di polietilenossido (PEO-like); il film barriera è ottenuto dal deposito di almeno uno strato, inorganico o organico, eventualmente con struttura simile ai polimeri di polietilenossido (PEO-like); ed i substrati su cui vengono fatti i depositi sono dispositivi medicochirurgici, manufatti di uso comune, strutture note come scaffold e le sostanze da rilasciare stesse. L’invenzione ha anche per oggetto i dispositivi medicochirurgici, i manufatti di uso comune e gli scaffold rivestiti con substrato e strato barriera, come pure le sostanze biologicamente attive rivestite con almeno uno strato barriera.

Cells positioned at the bottom of a Petri dish were exposed, in a home-made plasma source, to pulsed Dielectric Barrier Discharges operated in air in order to investigate the effect of the plasma species on their viability and growth. Processes with different number of pulse, respectively 1,3,9 and 27 pulse, were performed to study the influence on viability and cell growth of two different cell lines, Saos 2 and NHDF. Atmospheric air discharges applied on the two selected cell lines have shown an effect strongly dependent on cell type. At certain doses we have measured increased activity of the NHDF fibroblasts cell line. On the other side, an inhibition of cell adhesion and growth on the Saos 2 osteoblastoma cell line, directly dependent on the plasma doses, was clear. This study shows that by properly tuning the dose of exposure of cells to air plasma it is possible to induce both positive and negative effects on cell growth, that would be useful in several branches of Medicine.

Physical-chemical surface modifications represent a formidable tool to drive a suitable cell behavior on materials intended to be used in the biomedical field. Plasma processes are among the more powerful methods utilized to modify the surface of materials without altering their bulk intrinsic properties. In particular, by means of plasma treatment processes it is possible to graft chemical functional groups on polymer substrate. Functional groups grafted on the surface can improve per se cell adhesion and can also represent suitable anchor sites for biomolecule immobilization. The aim of this work was to determine the effect of plasma treatment and biomolecule immobilization on Polystyrene (PS) Petri dishes on the behavior of a human hepatocellular carcinoma cell line (HepG2). For this aim Petri dishes were grafted with N-containing groups in order to obtain grafted N-functionalities, to be used as anchor groups for the immobilization of galactosamine. In this way two different modified surfaces, NH3 grafted polystyrene (PS-NH3) and polystyrene owing galactosamine moieties (PS-NH3- GalNH2), have been obtained. Differences in cell morphology, urea and plasma Fibronectin (pFN) production were clearly observed on HepG2 seeded on PS-NH3 and PS-NH3- GalNH2. These results highlight the role of specific and non specific cell response in the in vitro study of materials intended to be used for biomedical purposes.

In order to improve the dispersion of multi-walled carbon nanotubes (MWCNTs) in aqueous media, their surface functionalization was carried out in O2-fed low-pressure plasmas. Differently from what can be found in the literature of this field, homogeneous functionalization was achieved by generating the plasma inside vials containing the nanotube powders properly stirred. Experimental parameters, such as input power, treatment time and pressure, were varied to investigate their influence on the process efficiency. A detailed characterization of the plasma treated nanotubes, dry and in aqueous suspension, was carried out with a multi-diagnostic analytical approach, to evaluate their surface chemical properties, morphology, structural integrity and stability in the colloidal state. The plasma grafting of polar ionizable (e.g. acid) groups has been proved to successfully limit the agglomeration of MWCNTs and to produce nanotubes suspensions that are stable for one month and more in water.

Cold plasma processes for surface engineering of biomaterials and biomedical devices are traditionally performed at low pressure; more and more, though, surface modification plasma processes at atmospheric pressure are also gaining popularity. This short review is aimed to list briefly atmospheric pressure plasma processes reported, in the last decade, for adapting the surface of materials to the best interactions with cells, bacteria and biomolecules.

Uniform cellular distribution is a prerequisite to forming tissue within porous scaffolds, but the seeding process often results in preferential adhesion of cells at the periphery. We develop a vapour phase coating strategy which is readily applicable to any porous solid to provide a uniform cellular distribution. Plasma polymerized allyl amine (ppAAm) is used to form a thin nitrogen-containing coating throughout porous three-dimensional (3-D) poly(D,L.-lactic acid) scaffolds. Subsequent controlled deposition of a hydrocarbon plasma polymerized hexane (ppHex) allows control of the fibroblast penetration into these porous 3-D objects. In order to optimize the coating conditions, a planar pinhole model of plasma penetration into pores is developed to rapidly measure deposit penetration using picolitre water contact angle measurement. Sufficiently good control over the plasma deposition within the porous scaffold is achieved using this approach to superimpose a relatively cell-repellent ppHex coating at the scaffold periphery onto the ppAAm-coated core, with a chemical gradient between the two. This 3-D chemical gradient encourages 3T3 fibroblast cells to adhere homogeneously from the periphery to the centre, when balanced by the tortuousity of the pore structure, which cells experience when passing from the surrounding medium to the centre.

In the most common approach of tissue engineering, a polymeric scaffold with a well-defined architecture has emerged as a promising platform for cells adhesion and guide their proliferation and differentiation into the desired tissue or organ. An ideal model for the regeneration should mimic clinical conditions of tissue injury, create a permissive microenvironment for diffusion of nutrients, gases and growth factors and permit angiogenesis. In this work, we used a 3D support made of synthetic resorbable polylactic acid (PLLA), which has considerable potential because of its well-known biocompatibility and biodegradability. One of the factors that influence cell adhesion to the scaffold is its porosity degree, but surface properties represent the main driving forces that influence the composition and orientation of proteins that will be absorbed onto material surfaces. We used scaffolds in which it was possible to control pore size and that had undergone on type-I collagen treatment, to mimic the extra cellular matrix, or plasma enhanced chemical vapor deposition (PE-CVD) combined with plasma treatment, in order to modify surface chemistry of the material. Our results show different cell affinity in non-treated scaffolds compared to type-I collagen or plasma modified ones. These surface changes are of considerable interest for tissue engineering and other areas of biomaterials science, where it can be useful to improve the surface of biomedical polymers to facilitate the colonization of the structure by the cells and obtain a more rapid regeneration or tissue replacement.

Thin films were deposited from a mixture of ethylene and acrylic acid in RF (13.56 MHz, parallel plate) glow discharges in different experimental conditions to obtain substrate-adherent coatings stable in water, surface-functionalized with tunable density of carboxyl groups. The surface composition of the coatings as well as their stability in water was investigated by X-ray Photoelectron Spectroscopy measurements and Toluidine Blue-O derivatization of the carboxylic acid functionalities. Coatings stable in water media were obtained, with tunable surface density of -COOH groups, of possible interest in biomedical applications. Such coatings were used in cell culture experiments with Saos-2 osteoblast cell lines.

Processo per la produzione mediante deposizione plasmochimica di un film di spessore nanometrico, eventualmente multistrato, che consente di eseguire in modo controllato, uniforme e duraturo, il rilascio di sostanze di interesse in un terreno circostante contenente liquidi, da un substrato che include la sostanza a essere rilasciati come particelle micro / nano o da uno strato depositato sul substrato, compresa la sostanza da rilasciare sotto forma di particelle micro / nano, o da uno strato della sostanza da rilasciare depositato sul substrato o da un substrato che è il sostanza da rilasciare facoltativamente sotto forma di particelle. Le sostanze da rilasciare possono essere metalli, composti aventi proprietà anti-batteriche, molecole biologicamente attive come farmaci, ormoni, estratti vegetali, peptidi, lipidi, protidi e glucidi. Lo strato con la sostanza da rilasciare, sia essa organica o inorganica, è ottenuto mediante deposizione plasmochimica facoltativamente avente una struttura simile al polietilenossido (PEO) o polietilenglicole (PEG), detti polimeri PEO-simili, costituiti, in una percentuale variabile da unità di ossido di etilene (-CH2CH2O-, EO); il film barriera è ottenuto depositando per plasma almeno uno strato organico o inorganico, opzionalmente con una struttura simile a PEO, in cui composizione chimica, grado di reticolazione e spessore sono regolabili dai parametri del processo di deposizione chimica plasmo e consentono di regolare il rilascio di la sostanza attiva in base alle esigenze specifiche. Le strutture su cui possono essere depositati i suddetti film sono: dispositivi medico-chirurgici, lavori manuali comuni, strutture note come scaffold e le sostanze sopra definite da rilasciare loro stesse. L'invenzione riguarda anche dispositivi medico-chirurgici, lavori manuali e scaffold rivestiti da un substrato e strato barriera, nonché a sostanze biologicamente attive rivestite da almeno uno strato barriera.

One embodiment of the invention provides a method of manufacturing a filter material such as carbon suitable for use in a smoking article. The method includes modifying the filtration properties of the filter by altering the surface of the filter material. The surface alteration is performed by plasma processing and can be used, for example, to increase the acidic or basic properties of the surface. Another embodiment of the invention provides a filter produced by such a method.

Process for the production by plasmochemical deposition of a film having a nanometric thickness, optionally multilayered, permitting carrying out in a controlled, uniform and long lasting way, release of substances of interest in a surrounding medium containing liquids, from a substrate including the substance to be released as micro/nano particles, or from a layer deposited on the substrate including the substance to be released as micro/nano particles, or from a layer of the substance to be released deposited on the substrate, or from a substrate that is the substance to be released optionally in the form of particles. The substances to be released can be metals, compounds having anti-bacterial properties, biologically active molecules such as drugs, hormones, vegetable extracts, peptides, lipids, protides and glucides. The layer with the substance to be released, be it organic or inorganic, is obtained by plasmochemical deposition optionally having a structure similar to polyethylene oxide (PEO) or polyethylene glycol (PEG), called PEO-like polymers, constituted, in a variable percentage da ethylene oxide units (-CH2CH2O-, EO); barrier film is obtained by depositing by plasma at least one organic or inorganic layer, optionally with a PEO-like structure, wherein chemical composition, degree of crosslinking and thickness are adjustable by the plasmo chemical deposition process parameters, and allow to adjust the release of the active substance according to specific needs. The structures on which the above said films can be deposited are: medical-surgical devices, common handworks, structures known as scaffolds, and the above defined substances to be released themselves. The invention also relates to medical-surgical devices, common handworks and scaffolds coated by a substrate and barrier layer, as well as to biologically active substances coated by at least one barrier layer.

Process for the production by plasmochemical deposition of a film having a nanometric thickness, optionally multilayered, permitting carrying out in a controlled, uniform and long lasting way, release of substances of interest in a surrounding medium containing liquids, from a substrate including the substance to be released as micro/nano particles, or from a layer deposited on the substrate including the substance to be released as micro/nano particles, or from a layer of the substance to be released deposited on the substrate, or from a substrate that is the substance to be released optionally in the form of particles. The substances to be released can be metals, compounds having anti-bacterial properties, biologically active molecules such as drugs, hormones, vegetable extracts, peptides, lipids, protides and glucides. The layer with the substance to be released, be it organic or inorganic, is obtained by plasmochemical deposition optionally having a structure similar to polyethylene oxide (PEO) or polyethylene glycol (PEG), called PEO-like polymers, constituted, in a variable percentage da ethylene oxide units (-CH2CH2O-, EO); barrier film is obtained by depositing by plasma at least one organic or inorganic layer, optionally with a PEO-like structure, wherein chemical composition, degree of crosslinking and thickness are adjustable by the plasmo chemical deposition process parameters, and allow to adjust the release of the active substance according to specific needs. The structures on which the above said films can be deposited are: medical-surgical devices, common handworks, structures known as scaffolds, and the above defined substances to be released themselves. The invention also relates to medical-surgical devices, common handworks and scaffolds coated by a substrate and barrier layer, as well as to biologically active substances coated by at least one barrier layer.

The present invention deals with a process for the realization of labels endowed with an invisible identification drawing to use as an effective method for preventing counterfeiting. This is based on treatments able to give different surface properties to different domains of polymeric materials, paper materials and materials of other kind (e.g. hydrophilic areas alternating with other hydrophobic areas, areas with charge alternating with neutral areas, acid areas alternating with basic areas, etc) according to pre-set drawings, by means of an appropriate system of masks. The drawing obtained with our method will be totally invisible to the naked eye, but a commercial highlighter runned over the labels will allow to highlight a secret drawing applied to the batch identified by the said labels.

La società ha come oggetto: ricerca e sviluppo tecnologico e industriale nel campo dei processi via plasma di modificazione superficiale dei materiali.