Protein immobilized reductants

Apply to the column 1.0ml of protein solution (dissolved in equilibration buffer-2) to be reduced. The inclusion of a denaturant in the solution deforms the protein structure so that inner disulfides are available to the immobilized reductant. Without the presence of guanidine or another deforming agent (i.e., urea, SDS, etc.), only partial reduction of the protein is possible. 

Fig. 5 Reversible oxidation and reduction of electroactive SAMs to generate renewable microarray surfaces for bioanalysis left). Corresponding fluorescent micrographs (right) depicting three cycles of carbohydrate and protein immobilization and release on the same substrate...

Zhao et al. [103] proposed the immobilization of myoglobin on the surface of MWCNT-modified GCE. They foimd that the protein immobilized can catalyze the reduction of hydrogen peroxide. The pH selected for the analysis was 4.0 and under these conditions, the response of the biosensor was very fast, reaching the 90% in 6 s. The relationship between current and hydrogen peroxide concentration was linear up to 330 pM, the reproducibility was 5.9 % and the detection limit was 4.2 pM under anaerobic conditions. The voltammetric response did not change significantly after 1 month at 4 °C or 1 week stored in air. 

Periodate Oxidation mainly of polysaccharide supports has become a popular activation technique for protein immobilization [149]. Sodium periodate (Nal04) can react with vicinal cw-hydroxyl groups on cellulose, dextran, or any other diols to produce aldehyde groups. These aldehyde groups can easily be transformed into secondary amines by reductive oxidation or to hydrazides by reaction with dihydrazine. Further attachment of ligands or spacer molecules can be performed via primary amino groups. 

Reduce-IMM. [Pieioe Chem.] Immobilized reductant for proteins. 

In another investigation, ELP[V5L2G3-90] with three lysines in the N-terminal region was immobihzed on a glass surface in a microreactor to enable temperature-controlled positioning of ELP fusion proteins. For this purpose, the glass surface was first functionalized with A -2-(aminoethyl)-3-aminopropyltrimethoxysilane, followed by glutaraldehyde treatment and reductive amination to immobilize the biopolymer on the surface (Fig. 17b) [132]. 

The biomembrane-like films can provide a favorable microenvironment for proteins and enhance direct electron-transfer rate between proteins and electrodes, so many biopolymers such as methyl cellulose (MC) and dihexadecylphospate (DHP) have been used to immobilize Mb and make biosensors [230-232], The electrochemical catalytic reduction of oxygen by the Mb-MC/EPG was examined by CVs. Mb-MC... 

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