Protein adsorption, as the primary process occurring when a foreign surface comes into contact with biosystem, was studied on thin polymer brush films consisting of poly(N-isopropylacrylamide) (PNIPAAm) and poly(2-vinylpyridine) (P2VP). These were prepared by "grafting to" method. The protein resistance stimuli responsive PNIPAAm-brushes toward serum albumin recorded compared adsorption P2VP brushes. To achieve better understanding resistance, PNIPAAm brushes different molecular weights...

Silk has a robust clinical track record and is emerging as promising biopolymer for drug delivery, including its use nanomedicine. However, silk-based nanomedicines still require further refinements full exploitation of their potential; the application "stealth" design principals especially necessary to support evolution. The aim this study was develop examine potential PEGylated silk nanoparticles an anticancer delivery system. We first generated B. mori derived by driving β-sheet assembly...

Temperature-sensitive poly(N-isopropylacrylamide) (PNIPAAm) brushes with different molecular weights Mn and grafting densities σ were prepared by the "grafting-to" method. Changes in their physicochemical properties according to temperature investigated help of situ spectroscopic ellipsometry attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy. Brush criteria indicate a transition between brush conformation below lower critical solution (LCST) an intermediate...

We report on the immobilization of gold nanoparticles end-functionalized and solvent responsive polystyrene brushes, grafted an underlying substrate. The presence brushes was confirmed by atomic force microscopy (AFM) X-ray photoelectron spectroscopy (XPS). resulting polystyrene−Au nanoassemblies have been used as nanosensors for detection a variety organic solvents in surrounding media. sensing mechanism is based upon change proximity immobilized consequence induced reversible...

Mixed polymer brushes as functional ultra thin films for surface functionalization have an enormous potential to create a variety of smart, switchable, and multifunctional surfaces films. It is shown how computer simulations can contribute better understanding the switching behavior brushes. Furthermore, it described be used with switchable ultrahydrophobicity wettability gradients, well layers immobilization nanoparticles. Applications these versatile brush coatings are envisioned in many...

We report on a facile route for the immobilization of silver nanoparticles (Ag NPs) onto pH-responsive poly(2-vinylpyridine) (P2VP) brushes. The process involves chemical grafting P2VP chains underlying substrate in brush conformation followed by situ synthesis Ag NPs via reduction nitrate (AgNO3) presence effect various reaction parameters, such as employed concentration AgNO3 salt and time process, has been demonstrated. quantitative analysis loaded amount surface coverage polymer brushes...

With a coupled spectroscopic ellipsometry-quartz crystal microbalance with dissipation (QCM-D) experimental setup, quantitative information can be obtained about the amount of buffer components (water molecules and ions) to poly(acrylic acid) (PAA) brush surface in swelling protein adsorption processes. PAA Guiselin brushes more than one anchoring point per single polymer chain were prepared. For swollen high was found brush-solution interface addition content inside layer. Upon bovine serum...

A versatile water-method for the controlled growth of Ag nanoparticles deposited onto surface SiO₂ spheres is developed. The nanohybrid systems exhibited exceptional SERS and catalytic properties.

In this study, we report on the fabrication of nanoassemblies composed by Au and bimetallic core–shell Au@Ag nanorods immobilized onto pH-responsive poly(2-vinylpyridine) (P2VP) brushes. The general process includes synthesis gold (through seed mediated method) a subsequent reduction AgNO3 surface. These colloidal particles were carboxy-terminated P2VP brushes (COOH-P2VP), previously grafted underlying substrates (silicon wafers glass slides). UV–vis spectroscopy transmission electron...

Controlling the reversibility, quantity, and extent of biomolecule interaction at interfaces has a significant relevance for biomedical biotechnological applications, because protein adsorption is always first step when solid surface gets in contact with biological fluid. Polymer brushes, composed end-tethered linear polymers sufficient grafting density, are very promising to control alter interactions systems their unique structure distinct collaborative response environmental changes. We...

Polymer brush surfaces that alter their physical properties in response to chemical stimuli have the capacity be used as new surface-based sensing materials. For such surfaces, detecting polymer conformation is key capabilities. Herein, we report on FRET-integrated ultrathin (<70 nm) exhibit stimuli-dependent FRET with changing conformation. Poly(N-isopropylacrylamide) polymers were chosen due exceptional sensitivity liquid mixture compositions and ability assembled into well-defined...

The pH-dependent switching of a poly(acrylic acid) (PAA) polyelectrolyte brush was investigated in situ using infrared spectroscopic ellipsometry (IRSE). synthesized by "grafting to" procedure on silicon substrate with native oxide layer. overall thickness the PAA dry state ∼5 nm. Reversible polymer studied at titration from pH 2 to 10 and back steps 1 unit. process observed monitoring characteristic vibrational bands carboxylic groups molecules. Decreasing C═O band amplitude arising COO−...

In this study, we report on the fabrication of nanoassemblies consisting poly(N-isopropyl acrylamide) (PNIPAAm) brushes immobilized with gold nanoparticles (Au NPs). The employed process involves grafting carboxyl terminated PNIPAAm chains an underlying substrate in a brush conformation followed by immobilization surface functionalized Au NPs means physical interaction (hydrogen bonding). Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and UV−vis have been to...

Abstract The ability to vary, adjust, and control hydrophobic interactions is crucial in manipulating between biological objects the surface of synthetic materials aqueous environment. To this end a grafted polymer layer (multi‐component mixed brush) synthesized that capable reversibly exposing nanometer‐sized fragments at its hydrophilic tuning, turning on, off interactions. reversible switching occurs response changes environment alters strength range attractive or amphiphilic probes...

Catalysis by enzymes on surfaces has many applications. However, strategies for efficient enzyme immobilization with preserved activity are still in need of further development. In this work, we investigate polyelectrolyte brushes prepared both grafting-to and grafting-from the aim to achieve high catalytic activity. For comparison, self-assembled monolayers that bind same chemical interactions included. We use model glucose oxidase two kinds polymers: anionic poly(acrylic acid) cationic...

Polymer brushes, consisting of densely end-tethered polymers to a surface, can exhibit rapid and sharp conformational transitions due specific stimuli, which offer intriguing possibilities for surface-based sensing the stimuli. The key toward unlocking these is development methods readily transduce signals from polymer changes. Herein, we report on single-fluorophore integrated ultrathin (<40 nm) brush surfaces that changing fluorescence properties based conformation. basis our change in...

Binary brushes constituted from two incompatible polymers can be used in the form of ultrathin polymeric layers as a versatile tool for surface engineering to tune physicochemical characteristics such wettability, charge, chemical composition, and morphology furthermore create responsive properties. Mixed oppositely charged weak polyelectrolytes represent special case responding surfaces that are sensitive changes pH value aqueous environment therefore interesting tools biosurface...

The AFM colloidal probe technique was used to measure the interaction between microsized silica spheres and annealed polyelectrolyte brushes made of poly(acrylic acid) (PAA) poly(2-vinyl pyridine) (P2VP) in KCl solutions various pH values salt concentrations. energy showed a distance dependence that affected strongly by swelling electric properties brushes. Between PAA particles, repulsive has been observed for all concentrations reflecting brush with varying value transition from osmotic...

Abstract The ability of a mixed polymer brush consisting poly( N ‐isopropyl acrylamide) (PNIPAAM) and poly(acrylic acid) (PAA) to modify physicochemical interfacial properties is presented. answer the binary toward changes environmental conditions like temperature, salt concentration, pH value was investigated by in situ spectroscopic VIS‐ellipsometry as well AFM contact angle mesurements dry state compared with behavior corresponding homopolymer brushes. A coupled swelling PNIPAAm PAA could...

The protein-adsorbing and -repelling properties of various smart nanometer-thin polymer brushes containing poly(N-isopropylacrylamide) poly(acrylic acid) with high potential for biosensing biomedical applications are studied by in situ infrared-spectroscopic ellipsometry (IRSE). IRSE is a highly sensitive nondestructive technique that allows protein adsorption on to be investigated an aqueous environment as external stimuli, such temperature pH, varied. These changes relevant conditions...