Biochemical applications of ultrathin films of enzymes, polyions and DNA

Abstract

This feature article summarizes recent applications of ultrathin films of enzymes and DNA assembled layer-by-layer (LbL). Using examples mainly from our own research, we focus on systems developed for biocatalysis and biosensors for toxicity screening. Enzyme-poly(L-lysine) (PLL) films, especially when stabilized by crosslinking, can be used for biocatalysis at unprecedented high temperatures or in acidic or basic solutions on electrodes or sub-micron sized beads. Such films have bright prospects for chiral synthesis and biofuel cells. Excellent bioactivity and retention of enzyme structure in these films facilitates their use in detailed kinetic studies. Biosensors and arrays employing DNA-enzyme films show great promise in predicting genotoxicity of new drug and chemical product candidates. These devices combine metabolic biocatalysis, reactive metabolite-DNA reactions, and DNA damage detection. Catalytic voltammetry or electrochemiluminescence (ECL) can be used for high throughput arrays utilizing multiple LbL "spots" of DNA, enzyme and metallopolymer. DNA-enzyme films can also be used to produce nucleobase adduct toxicity biomarkers for detection by LC-MS. These approaches provide valuable high throughput tools for drug and chemical product development and toxicity prediction.

Layer-by-Layer films based on biopolymers extracted from red seaweeds and polyaniline for applications in electrochemical sensors of chromium VI

“…Amongst the preparation methods for thin films of soft materials, the Layer-by-Layer (LbL) self-assembly technique has received recent attention partly due to its experimental simplicity, and because it enables studies of molecular interactions between a wide variety of materials [3,4]. In addition, when working with materials in the form of thin films, rather than as powder or solution, it is possible to obtain highly organized structures at the molecular level and controlling the thickness of according to the purpose of study or application for the film.…”

On the Behavior of Boron Nitride Nanotube-Flavin Adenine Dinucleotide Interaction Ion Implantation Order to Design Biofuel Cells

“…3 4 Electron transfer has been gotten for many enzymes by immobilizing them within thin films of various sorts on an electrode. [5][6][7][8][9] Glucose oxidase (GOX) based glucose oxidizing electrodes have attracted attention as candidate for bio catalytic fuel cell anodes. The FAD/FADH 2 redox cofactor of GOX has a sufficiently negative formal potential for a biofuel cell anode.…”

Differential Photoluminescent and Electrochemiluminescent Detection of Anions with a Modified Ruthenium(II)–Bipyridyl Complex

“…[22][23][24][25] The increasing interest in ECL over the past two decades is reflected in the growing number of its analytical applications. [22][23][24][25][26] ECL has also been commercially developed for the clinical diagnostic market (e.g., immunoassays and nucleic acid assays). [27][28][29] Indeed, ECL allows highly sensitive and selective detection of various analytes.…”