Whole-cell Gluconobacter oxydans biosensor for 2-phenylethanol biooxidation monitoring.

A microbial biosensor for 2-phenylethanol (2-PE) based on the bacteria Gluconobacter oxydans was developed and applied in monitoring of a biotechnological process. The cells of G. oxydans were immobilized within a disposable polyelectrolyte complex gel membrane consisting of sodium alginate, cellulose sulphate and poly(methylene-co-guanidine) attached onto a miniaturized Clark oxygen electrode, forming whole cell amperometric biosensor.

Analysis of ethanol in fermentation samples by a robust nanocomposite-based microbial biosensor.

A robust microbial biosensor was constructed from a bionanocomposite prepared by a direct mixing of bacterial cells of Gluconobacter oxydans and carbon nanotubes with ferricyanide employed as a mediator for enhanced sensitivity of ethanol oxidation. A successful integration of the device into flow injection analysis mode of operation provided a high sensitivity of detection of (74 ± 2.7) μA mM(-1) cm(-2), a low detection limit of 5 μM and a linear range from 10 μM up to 1 mM.

A hyaluronic acid dispersed carbon nanotube electrode used for a mediatorless NADH sensing and biosensing.

A biocompatible nanocomposite consisting of single-walled carbon nanotubes (CNTs) dispersed in a hyaluronic acid (HA) was investigated as a sensing platform for a mediatorless electrochemical detection of NADH. The device was characterised by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and extensively by electrochemistry. CNT-HA bionanocomposite showed more reversible electrochemistry, higher short-term stability of NADH sensing and higher selectivity of NADH detection compared to frequently used CNT-CHI (chitosan) modified GCE.

Off-line FIA monitoring of D-sorbitol consumption during L-sorbose production using a sorbitol biosensor.

A ferricyanide mediated amperometric biosensor system implementing D-sorbitol dehydrogenase together with diaphorase for sensitive detection of D-sorbitol was used. The biosensor system was successfully integrated into an off-line FIA system with a throughput of detection of 10 h(-1). The device exhibited limit of detection of 20 microM with an average relative standard deviation of analysis of samples of 2.

A novel microbial biosensor based on cells of Gluconobacter oxydans for the selective determination of 1,3-propanediol in the presence of glycerol and its application to bioprocess monitoring.

Novel and selective microbial amperometric biosensors that use Gluconobacter oxydans cells to monitor the bacterial bioconversion of glycerol (Gly) to 1,3-propanediol (1,3-PD) are described. Two different mediators, ferricyanide and flexible polyvinylimidazole osmium functionalized polymer (Os-polymer), were employed to prepare two different microbial biosensors, both of which gave high detection performance. The good operational stabilities of both types of biosensor were underlined by the ability to detect 1,3-PD throughout 140 h of continuous operation.

Development of enzyme flow calorimeter system for monitoring of microbial glycerol conversion.

Glycerokinase from Cellulomonas sp. was used to develop biosensor based on flow calorimetry for quantitative analysis of glycerol during bioconversion process. An automatic flow injection analysis device with the glycerol biosensor was built and tested during growth on glycerol of 1,3-propanediol-producing bacteria.