Tunable layer-by-layer films containing hyaluronic acid and their interactions with CD44
Layer by layer (LbL) assembly is the hierarchical and controlled association of oppositely charged polyelectrolytes (PEs). It is usually applied to generate coatings or self-standing membranes relevant for different technological fields.1,2 In the biomedical area, biodegradable and biocompatible PEs have been used to generate LbL-based drug delivery systems;3 substrates that induce stem cell differentiation;4 surfaces…
Influence of the sulfation degree of glycosaminoglycans on their multilayer assembly with poly-l-lysine
We report on the build-up and the intrinsic properties of polyelectrolyte multilayer films from poly-l-lysine and glycosaminoglycans (GAGs) with different sulfation degree, i.e. different charge. We used three complementary techniques, namely electrokinetic analysis (EKA), quartz-crystal microbalance with dissipation (QCM-D) and surface plasmon resonance (SPR), to characterize the assembly process and to assess the properties of…
Biofunctionalization of titanium surface with multilayer films modified by heparin-VEGF-fibronectin complex to improve endothelial cell proliferation and blood compatibility
In-stent restenosis and subsequent thrombosis remain a significant complication following the implantation of coronary stents. Different approaches have been used in developing novel coronary stents to protect against thrombosis and minimize restenosis. In the present study, we designed a biomacromolecular layer-by-layer coating with heparin, vascular endothelial growth factor (VEGF), and bronectin onto nickel-free titanium surface…
Layer-by-layer assembly of lysozyme with iota-carrageenan and gum Arabic for surface modification of food packaging materials with improved barrier properties
The study aimed to investigate the surface modification of biaxially oriented polypropylene (BOPP) by layer-by-layer (LbL) assembly of lysozyme (LZ) with two different polysaccharides, iota-carrageenan (IC) and gum arabic (GA), for food packaging applications. The effects of solution pH, adsorption time, elimination of intermediate drying steps were investigated. The LbL film growth was monitored up…
Development of a novel biosensor for Creatine Kinase (CK-MB) using Surface Plasmon Resonance (SPR)
In this paper, we report a new biosensor for detection of the cardiac biomarker Creatine Kinase (CK-MB) using Surface Plasmon Surface (SPR) technique, with the purpose of the diagnosis of Acute Myocardial Infarction (AMI). For this, we employed gold nanoparticles (AuNP) stabilized with Cysteamine (Cys), and functionalized with Creatine Phosphate (Pcrea), which promote an increase…
Continuous assembly of supramolecular polyamine–phosphate networks on surfaces: preparation and permeability properties of nanofilms
Supramolecular self-assembly of molecular building blocks represents a powerful “nanoarchitectonic” tool to create new functional materials with molecular-level feature control. Here, we propose a simple method to create tunable phosphate/polyamine-based films on surfaces by successive assembly of poly(allylamine hydrochloride) (PAH)/phosphate anions (Pi) supramolecular networks. The growth of the films showed a great linearity and regularity…
Enzyme Multilayers on Graphene-Based FETs for Biosensing Applications
Electrochemical sensors represent a powerful tool for real-time measurement of a variety of analytes of much significance to different areas, ranging from clinical diagnostics to food technology. Point-of-care devices which can be used at patient bedside or for online monitoring of critical parameters are of great importance in clinical daily routine. In this work, portable, low-cost…
Cascading reaction of arginase and urease on a graphene-based FET for ultrasensitive, real-time detection of arginine
Herein, a biosensor based on a reduced graphene oxide field effect transistor (rGO-FET) functionalized with the cascading enzymes arginase and urease was developed for the detection of L-arginine. Arginase and urease were immobilized on the rGO-FET sensing surface via electrostatic layer-by-layer assembly using polyethylenimine (PEI) as cationic building block. The signal transduction mechanism is based on the ability of the cascading enzymes to selectively perform chemical transformations and…
Layer-by-layer self-assembly for carbon dots/chitosan-based multilayer: Morphology, thickness and molecular interactions
Oxidized Carbon dots, prepared from the acid dehydration of cellulose, were used in the preparation of self-assembled films with the biopolymer chitosan. The morphology, thickness and molecular interactions of the films were characterized with a variety of techniques including AFM, FTIR, UV–Vis and Surface Plasmon Resonance (SPR) spectroscopy. We noticed an increase in the thickness…