PLCL/PCL Dressings with Platelet Lysate and Growth Factors Embedded in Fibrin for Chronic Wound Regeneration.

Introduction: The formation of diabetic ulcers (DU) is a common complication for diabetic patients resulting in serious chronic wounds. There is therefore, an urgent need for complex treatment of this problem. This study examines a bioactive wound dressing of a biodegradable electrospun nanofibrous blend of poly(L-lactide-co-ε-caprolactone) and poly(ε-caprolactone) (PLCL/PCL) covered by a thin fibrin layer for sustained delivery of bioactive molecules.

Vascular Response on a Novel Fibrin-Based Coated Flow Diverter.

Purpose: Due to thromboembolic complications and in-stent-stenosis after flow diverter (FD) treatment, the long-term use of dual antiplatelet treatment (DAPT) is mandatory. The tested nano-coating has been shown to reduce material thrombogenicity and promote endothelial cell proliferation in vitro. We compared the biocompatibility of coated (Derivo Heal) and non-coated (Derivo bare) FDs with DAPT in an animal model.

The Effect of a Polyester Nanofibrous Membrane with a Fibrin-Platelet Lysate Coating on Keratinocytes and Endothelial Cells in a Co-Culture System.

Chronic wounds affect millions of patients worldwide, and it is estimated that this number will increase steadily in the future due to population ageing. The research of new therapeutic approaches to wound healing includes the development of nanofibrous meshes and the use of platelet lysate (PL) to stimulate skin regeneration. This study considers a combination of a degradable electrospun nanofibrous blend of poly(L-lactide--ε-caprolactone) and poly(ε-caprolactone) (PLCL/PCL) membranes (NF) and fibrin loaded with various concentrations of PL aimed at the development of bioactive skin wound healing dressings.

Accelerated in vitro recellularization of decellularized porcine pericardium for cardiovascular grafts.

An ideal decellularized allogenic or xenogeneic cardiovascular graft should be capable of preventing thrombus formation after implantation. The antithrombogenicity of the graft is ensured by a confluent endothelial cell layer formed on its surface. Later repopulation and remodeling of the scaffold by the patient's cells should result in the formation of living autologous tissue.

Endothelialization of an ePTFE vessel prosthesis modified with an antithrombogenic fibrin/heparin coating enriched with bound growth factors.

Early and late thrombosis remain the most frequent reasons for the failure of synthetic cardiovascular grafts. Long-term hemocompatibility of implanted synthetic grafts can be achieved if a natural living endothelium is formed over its blood-contacting surface. Here we present a modification of a standard expanded polytetrafluorethylene (ePTFE) vessel prosthesis by a controlled preparation of a fibrin mesh enriched with covalently bound heparin and noncovalently bound vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF).

Hemocompatibility Testing of Blood-Contacting Implants in a Flow Loop Model Mimicking Human Blood Flow.

The growing use of medical devices (e.g., vascular grafts, stents, and cardiac catheters) for temporary or permanent purposes that remain in the body's circulatory system demands a reliable and multiparametric approach that evaluates the possible hematologic complications caused by these devices (i.

Human decellularized and crosslinked pericardium coated with bioactive molecular assemblies.

Decellularized human pericardium is under study as an allogenic material for cardiovascular applications. The effects of crosslinking on the mechanical properties of decellularized pericardium were determined with a uniaxial tensile test, and the effects of crosslinking on the collagen structure of decellularized pericardium were determined by multiphoton microscopy. The viability of human umbilical vein endothelial cells seeded on decellularized human pericardium and on pericardium strongly and weakly crosslinked with glutaraldehyde and with genipin was evaluated by means of an MTS assay.

Low-thrombogenic fibrin-heparin coating promotes in vitro endothelialization.

Long-term performance of implanted cardiovascular grafts can be ensured if living endothelium overgrows their surface. Surface modifications to implants are therefore being sought that can encourage endothelialization while preventing thrombus formation until the natural endothelium is formed. In the present study, heparin was covalently attached to a fibrin mesh grown from a polyvinyl chloride (PVC) substrate surface by the catalytic action of surface immobilized thrombin on a fibrinogen solution.

Ultralow-Fouling Behavior of Biorecognition Coatings Based on Carboxy-Functional Brushes of Zwitterionic Homo- and Copolymers in Blood Plasma: Functionalization Matters.

Fouling from complex biological fluids such as blood plasma to biorecognition element (BRE)-functionalized coatings hampers the use of affinity biosensor technologies in medical diagnostics. Here, we report the effects the molecular mechanisms involved in functionalization of low-fouling carboxy-functional coatings have on the BRE capacity and resistance to fouling from blood plasma. The specific mechanisms of EDC/NHS activation of carboxy groups, BRE attachment, and deactivation of residual activated groups on recently developed ultra-low-fouling carboxybetaine polymer and copolymer brushes (pCB) as well as conventional carboxy-terminated oligo(ethylene glycol)-based alkanethiolate self-assembled monolayers (OEG-SAMs) are studied using the polarization modulation infrared reflection/absorption spectroscopy, X-ray photoelectron spectroscopy, and surface plasmon resonance methods.

Protein nanocoatings on synthetic polymeric nanofibrous membranes designed as carriers for skin cells.

Protein-coated resorbable synthetic polymeric nanofibrous membranes are promising for the fabrication of advanced skin substitutes. We fabricated electrospun polylactic acid and poly(lactide--glycolic acid) nanofibrous membranes and coated them with fibrin or collagen I. Fibronectin was attached to a fibrin or collagen nanocoating, in order further to enhance the cell adhesion and spreading.

Plasmonic Hepatitis B Biosensor for the Analysis of Clinical Saliva.

A biosensor for the detection of hepatitis B antibodies in clinical saliva was developed. Compared to conventional analysis of blood serum, it offers the advantage of noninvasive collection of samples. Detection of biomarkers in saliva imposes two major challenges associated with the low analyte concentration and increased surface fouling.

Correction: Enhanced Mitogenic Activity of Recombinant Human Vascular Endothelial Growth Factor VEGF121 Expressed in E. coli Origami B (DE3) with Molecular Chaperones.

[This corrects the article DOI: 10.1371/journal.pone.

Copolymer Brush-Based Ultralow-Fouling Biorecognition Surface Platform for Food Safety.

Functional polymer coatings that combine the ability to resist nonspecific fouling from complex media with high biorecognition element (BRE) immobilization capacity represent an emerging class of new functional materials for a number of bioanalytical and biosensor technologies for medical diagnostics, security, and food safety. Here, we report on a random copolymer brush surface - poly(CBMAA-ran-HPMAA) - providing high BRE immobilization capacity while simultaneously exhibiting ultralow-fouling behavior in complex food media. We demonstrate that both the functionalization and fouling resistance capabilities of such copolymer brushes can be tuned by changing the surface contents of the two monomer units: nonionic N-(2-hydroxypropyl) methacrylamide (HPMAA) and carboxy-functional zwitterionic carboxybetaine methacrylamide (CBMAA).

Enhanced Mitogenic Activity of Recombinant Human Vascular Endothelial Growth Factor VEGF121 Expressed in E. coli Origami B (DE3) with Molecular Chaperones.

We describe the production of a highly-active mutant VEGF variant, α2-PI1-8-VEGF121, which contains a substrate sequence for factor XIIIa at the aminoterminus designed for incorporation into a fibrin gel. The α2-PI1-8-VEGF121 gene was synthesized, cloned into a pET-32a(+) vector and expressed in Escherichia coli Origami B (DE3) host cells. To increase the protein folding and the solubility, the resulting thioredoxin-α2-PI1-8-VEGF121 fusion protein was co-expressed with recombinant molecular chaperones GroES/EL encoded by independent plasmid pGro7.

Hepatitis B plasmonic biosensor for the analysis of clinical serum samples.

A plasmonic biosensor for rapid detection of protein biomarkers in complex media is reported. Clinical serum samples were analyzed by using a novel biointerface architecture based on poly[(N-(2-hydroxypropyl) methacrylamide)-co-(carboxybetaine methacrylamide)] brushes functionalized with bioreceptors. This biointerface provided an excellent resistance to fouling even after the functionalization and allowed for the first time the direct detection of antibodies against hepatitis B surface antigen (anti-HBs) in clinical serum samples using surface plasmon resonance (SPR).

The potential applications of fibrin-coated electrospun polylactide nanofibers in skin tissue engineering.

Fibrin plays an important role during wound healing and skin regeneration. It is often applied in clinical practice for treatment of skin injuries or as a component of skin substitutes. We prepared electrospun nanofibrous membranes made from poly(l-lactide) modified with a thin fibrin nanocoating.

Functionalizable low-fouling coatings for label-free biosensing in complex biological media: advances and applications.

This review focuses on recent advances in the development of functionalizable antifouling coatings and their applications in label-free optical biosensors. Approaches to the development of antifouling coatings, ranging from self-assembled monolayers and PEG derivatives to ultra-low-fouling polymer brushes, are reviewed. Methods of preparation and characterization of antifouling coatings and the functionalization of antifouling coatings with bioreceptors are reviewed, and the effect of functionalization on the fouling properties of biofunctional coating is discussed.

Surface plasmon resonance: advances of label-free approaches in the analysis of biological samples.

Surface plasmon resonance sensors have made vast advancements in the sensing technology and the number of applications achievable. New developments in surface plasmon resonance sensors have gained considerable momentum promoted by the urgent needs of fast, reliable and label-free methods for detection and quantification of analytes in molecular biology, medicine and other life sciences. However, even if enormous improvements in the limits of detections have been achieved, this technology still faces important challenges to be translated to clinical practice or in-field measurements.

Photo-patterning of non-fouling polymers and biomolecules on paper.

Functional cellulose substrates with tetrazole moieties are generated to serve as universal platforms for the spatio-temporal immobilization of synthetic ultra-low fouling polymer brushes and protein species via a nitrile imine-mediated tetrazole-ene cycloaddition (NITEC)-based protocol. Poly(carboxybetaine acrylamide) brushes are grafted from initiators photo-patterned by NITEC utilizing single electron transfer living radical polymerization. Streptavidin is photo-immobilized with remarkable efficiency, opening the possibility to generate new materials for biomedical and biosensing applications.

The gene expression of human endothelial cells is modulated by subendothelial extracellular matrix proteins: short-term response to laminar shear stress.

Vascular surgery for atherosclerosis is confronted by the lack of a suitable bypass material. Tissue engineering strives to produce bio-artificial conduits to provide resistance to thrombosis. The objectives of our study were to culture endothelial cells (EC) on composite assemblies of extracellular matrix proteins, and to evaluate the cellular phenotype under flow.

Diagnosis of Epstein-Barr virus infection in clinical serum samples by an SPR biosensor assay.

Label-free affinity biosensors offer a promising platform for the development of a new generation of medical diagnostic technologies. Nevertheless, when such sensors are used in complex biological media, adsorption of non-targeted medium components prevents the specific detection of the analyte. In this work, we introduce for the first time a biosensor assay based on surface plasmon resonance (SPR) capable of diagnosing different stages of Epstein-Barr virus (EBV) infections in clinical serum samples.

Functionalized ultra-low fouling carboxy- and hydroxy-functional surface platforms: functionalization capacity, biorecognition capability and resistance to fouling from undiluted biological media.

The non-specific binding of non-target species to functionalized surfaces of biosensors continues to be challenge for biosensing in real-world media. Three different low-fouling and functionalizable surface platforms were employed to study the effect of functionalization on fouling resistance from several types of undiluted media including blood plasma and food media. The surface platforms investigated in this work included two polymer brushes: hydroxy-functional poly(2-hydroxyethyl methacrylate) (pHEMA) and carboxy-functional poly(carboxybetaine acrylamide) (pCBAA), and a standard OEG-based carboxy-functional alkanethiolate self-assembled monolayer (AT-SAM).

Biomimetic non-fouling surfaces: extending the concepts.

In this study, we propose a substrate-independent biomimetic modification route for the creation of antifouling polymer brushes. This modification route consists of the formation/deposition of a biomimetic polydopamine anchor layer followed by a well-controlled surface-initiated atom transfer radical polymerization of antifouling polymer brushes initiated by 2-bromo-2-methylpropanoyl groups covalently attached to the hydroxyl and amine groups present in the anchor layer. In this way, we synthesized polymer brushes of methoxy- and hydroxy-capped oligoethylene glycol methacrylate, 2-hydroxyethyl methacrylate and carboxybetaine acrylamide.

Improved adhesion and differentiation of endothelial cells on surface-attached fibrin structures containing extracellular matrix proteins.

Currently used vascular prostheses are hydrophobic and do not allow endothelial cell (EC) adhesion and growth. The aim of this study was to prepare fibrin (Fb)-based two-dimensional (2D) and three-dimensional (3D) assemblies coated with extracellular matrix (ECM) proteins and to evaluate the EC adhesion, proliferation and differentiation on these assemblies in vitro. Coating of Fb with collagen, laminin (LM), and fibronectin (FN) was proved using the surface plasmon resonance technique.

Complete identification of proteins responsible for human blood plasma fouling on poly(ethylene glycol)-based surfaces.

The resistance of poly(ethylene glycol) (PEG) against protein adsorption is crucial and has been widely utilized in various biomedical applications. In this work, the complete protein composition of biofilms deposited on PEG-based surfaces from human blood plasma (BP) was identified for the first time using nanoLC-MS/MS, a powerful tool in protein analysis. The mass of deposited BP and the number of different proteins contained in the deposits on individual surfaces decreased in the order of self-assembling monolayers of oligo(ethylene glycol) alkanethiolates (SAM) > poly(ethylene glycol) end-grafted onto a SAM > poly(oligo(ethylene glycol) methacrylate) brushes prepared by surface initiated polymerization (poly(OEGMA)).