Optimisation of the enzyme-based determination of hydrogen peroxide using the quartz crystal microbalance.
The benzidines, 3,3'-diaminobenzidine (DAB), 3,3'-dimethoxybenzidine (DMOB) and 3,3',5,5'-tetramethylbenzidine (TMB) were enzymatically oxidised to detect hydrogen peroxide, using the quartz crystal. The oxidised product mainly remains in suspension, resulting in a limited quartz sensor signal. We have used two non-ionic surfactants, Tween 80 and Triton X-100 to interact with the oxidised amphiphilic products to increase their solubility and surface activity, and their ability to adsorb to the crystal surface. Tween 80 exhibits optimised response effects for DAB, DMOB and TMB at 0.012, 0.005, and 0.002% (v/v), respectively, whereas Triton X-100 is optimum at 0.1, 0.2, and 0.006% (v/v), respectively. As a result, we have improved the quartz crystal sensor sensitivity to peroxide. The use of Triton X-100 gave an improved response time.
Martin
S P
SP
Centre for Clinical Science and Measurement, School of Biomedical and Life Sciences, University of Surrey, Guildford, Surrey GU2 7XH, UK.
Lynch
J M
JM
Reddy
S M
SM
D001560:Benzidines / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D003460:Crystallization / Q000379:methods; D017097:Electric Impedance; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods; D006735:Horseradish Peroxidase / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000032:analysis*; D017830:Octoxynol / Q000737:chemistry; D010084:Oxidation-Reduction; D011136:Polysorbates / Q000737:chemistry; D011786:Quality Control; D011791:Quartz / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013501:Surface-Active Agents / Q000737:chemistry
D001560:Benzidines; D011136:Polysorbates; D013501:Surface-Active Agents; D011791:Quartz; D017830:Octoxynol; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase