Nano-assembly of glucose oxidase on thein situself-assembled films of polypyrrole and its optical, surface and electrochemical characterizations

Abstract

An in situ self-assembly technique with nanometre control over thicknesses and multilayered structures was used to manufacture the ultrathin films of polypyrrole (PPY). The PPY film was deposited on a polyanion, poly(styrene sulfonate) (PSS) modified surface as a function of time, previously PSS had been deposited on various substrates (glass, mica, indium-tin-oxide coated glass plates). Later, alternate PPY and PSS films were fabricated on such substrates using a layer-by-layer (LBL) technique. The glucose oxidase (GOD) molecules were also deposited on such self-assembled PPY films by the LBL technique. The PSS/PPY/GOD, PPY/PPY/GOD/poly(ethylene imine) (PEI)/GOD etc, film configurations were fabricated, and functionally as well as structurally characterized by UV-visible, electrochemical and scanning probe microscopy techniques, respectively. The results of a scanning probe microscopic study on the films were analysed to understand the molecular orientation of GOD on the PPY surface, and the dependence of the enzyme concentration for the depositing solutions. Moreover, the electrochemical studies performed provided information with respect to the electron transfer processes on the spatial arrangement of GOD molecules on the PPY surfaces. The immobilization of GOD on a conductive PPY represented a crucial and important step, and allowed us to construct the glucose-responsive biosensors.

In situ observation of the initial adsorption process of layer‐by‐layer sequential adsorbed polyelectrolyte film using an AFM

“…It can also be combined with other techniques [14], such as micro-printing [15,16] and the surface sol-gel method [17]. Organic light-emitting devices [6,16,18], nonlinear optical devices, solar cells [19][20][21], filters [22,23], and sensors [24] have also been studied and fabricated by using the layer-by-layer technique.…”

Hybrid Film Biosensor for Phenolic Compounds Detection

“…LbL deposition was used i.e. to incorporate Glucose oxidase (GOx) into a multilayer of poly(styrene sulfonic acid)/polypyrrole (PSS/PPY) on the surface of in-situ polymerized PPY (Ram et al, 2000).…”

“…To immobilize the receptor, it is bonded to the polymer matrix through covalent or noncovalent interaction. Physical adsorption (Lopez et al, 2006), the Langmuir-Blodgett technique (Cabaj et al, 2010ab), layer-by layer deposition technique (Ram et al, 2000), and mechanical embedding method (J. Kan et al, 2004) are used to bind the receptor to the matrix through noncovalent bonding.…”

Selective potentiometric determination of uric acid with uricase immobilized on ZnO nanowires

“…Recent advances in electrochemical biosensing based on a wide variety of nanostructures such as ZnO nanowires, nanotubes and nonporous materials have attracted great interest due to their remarkable properties like non-toxicity, bio-safety, excellent biological compatibility, high-electron transfer rates, enhanced analytical performance, increased sensitivity, ease of fabrication and low cost [25][26][27][28][29]. ZnO nanomaterials can be used in a variety of electrochemical biosensing schemes due to their unique advantages in combination with immobilized enzymes.…”

“…Also ZnO nanowires exhibited better performance in perspective of signal to noise ratio as compared to ZnO thin film [33] because the nanosurfaces have other chemical properties as well. These are the reasons why nanowires are more sensitive, have an extended detection limit and possess a fast response time as compared to a thin films [24][25][26][27][28][29][30][31][32][33][34][35].…”