Biosensors preparation

A. Salimi, R.G. Compton, and R. Hallaj, Glucose biosensor prepared by glucose oxidase encapsulated sol-gel and carbon-nanotube-modified basal plane pyrolytic graphite electrode. Anal. Biochem. 333, 49— 56 (2004). 

The RP-HPLC method based on the CL reaction of luminol (124) catalyzed by Co(II) (Section in.B.2.c) can be applied for determination of peroxycarboxylic acids, esters and diacyl peroxides (see examples of LOD in equation 67, Section V.B.2.c) . The biosensor prepared according to equation 70, that is effective in the determination of hydroperoxides (Section V.B.6.b), becomes deactivated after three days of operation when trying to determine t-butyl peracetate. ... 

Fig. 20.1. MAC Mode AFM three-dimensional images in air of (A) clean HOPG electrode (B) thin-film dsDNA-biosensor surface, prepared onto HOPG by 3 min free adsorption from 60 pg/mL dsDNA in pH 4.5 0.1 M acetate buffer (C) multi-layer film dsDNA biosensor, prepared onto HOPG by evaporation of three consecutive drops each containing 5pL of 50 pg/mL dsDNA in pH 4.5 0.1 M acetate buffer (D) thick-film dsDNA biosensor, prepared onto HOPG by evaporation from 37.5mg/mL dsDNA in pH 4.5 0.1M acetate buffer. With permission from Refs. [28,29].

F. Ricci and G. Palleschi, Sensor and biosensor preparation, optimisation and applications of Prussian Blue modified electrodes, Biosens. Bioelectron., 21 (2005) 389-407. 

GLUCOSE OXIDASE BIOSENSOR PREPARATION Enzyme immobilisation was carried out, at room temperature. 

A.M. Chiorcea-Paquim and A.M. Oliveira Brett 28.3 DNA ELECTROCHEMICAL BIOSENSORS PREPARATION... 

Thick-layer dsDNA biosensor prepare by covering the GCE surface with 10 pL of 35mgmL 1 dsDNA solution and allow it to dry in normal atmosphere. 

Multi-layer dsDNA biosensor prepare by successively covering the GCE (d = 1.5 mm) surface with three drops of 5pL each of 50 pgmL-1 dsDNA solution. After placing each drop on the electrode surface of the biosensor, dry under a constant flux of N2. 

Thin-layer dsDNA biosensor prepare by immersing the GCE in a 60 mgmL-1 dsDNA solution and apply a potential of +0.40 V during 10 min. 

Figure 1. Current-time curves of glucose biosensors prepared A) in depositing the mixture of glucose oxidase and AQ atop the platinum electrode and allowing the solvent to evaporate at room temperature, B) in covering this AQ-glucose oxidase film with a Nafion layer or C) in heating the AQ-glucose oxidase film at 50°C in an oven for 30 min. The assays were done with 20 mM of glucose at pH 7.

Figure 2. Effect of glucose oxidase concentration on the amperometric response to 20 mM glucose for biosensors prepared with different amounts of enzyme mixed with 25 il of AQ 1%. The AQ-glucose oxidase films were dried at 50°C during 30 min in an oven.

Reprinted from Biosensors and bioelectronics, 17(6-7), Henke L, Nagy N, Krull UJ, An AFM determination of the effects on surface roughness caused by cleaning of fused silica and glass substrates in the process of optical biosensor preparation, 547-551, 2002, with permission from Elsevier. 

Kobayashi, Y. Hoshi, T. Anzai, J. Glucose and lactate biosensors prepared by a layer-by-layer deposition of eoneanavalin A and mannose-labeled enzymes electrochemical response in the presence of electron mediators. Chem. Pharm. Bull. 2001, 49, 755. 

Similar to the behavior of Nafion, poly(ester sulphonic acid) ionomers selectively exclude anionic species and large particles, but cations and neutral molecules are permeable. Of the three Eastman Kodak AQ 29, AQ 38, and AQ 55 polymers, AQ 55 (see the polymer backbone in Fig. 11.12) is the most studied and most applied in biosensor preparation. Wang and coworkers described have features of this polymer as an electrode material, including strong affinity toward hydrophobic counterions, prevention of electrode fouling from proteins, stability of the polymer film on the electrode, ability to preconcentrate catalysts in the film, and lowering the overpotential of many species difficult to oxidize or reduce. Several workers also showed that this poly(ester sulphonic acid) polymer is very stable as an organic phase electrode material. ... 

Three procedures used in the DNA-electrochemical biosensor preparation by adsorption with or without applied potential, and their characterisation by AFM, are shown in Fig. 6.1 ... 

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