Effect of GLYMO/TEOS/MTEOS Sol-Gel Film Thickness on the Responses of Glucose Biosensor

Abstract

In the present study, the effect of the film thickness on the responses of a glucose biosensor was investigated. The modified platinum electrodes used in the study were constructed by immobilization of glucose oxidase under a film layer of the sol-gel coating solution. The sol-gel coating solutions were prepared by using (3-Glycidoxylpropyl) trimethoxysilane (GLYMO), tetraethoxysilane (TEOS), and methyltriethoxysilane (MTEOS). Electrochemical measurements were carried out amperometrically by determining hydrogen peroxide released by the enzymatic reaction between glucose and glucose oxidase. It was found that the amperometric responses of the sensor decreased with increasing the volume of coating solution dropped on the adsorbed enzyme. It was determined that the film thickness has a significantly influence on the sensor responses. It was observed that the amperometric responses decreased by 85% when the volume of the coating solution dropped on the electrode increased from 4 µL to 12 µL.

Keywords

• Biosensor; glucose; glucose oxidase; sol-gel

References

1. 1. Li J, Chia L.S., Goh N.K., Tan S.N., Ge H. Mediated amperometric glucose sensor modified by the sol-gel method, Sens Actuators B,1997;40:135-141. DOI:10.1016/S0925-4005(97)80252-3
2. 2. Chaubey A, Malhotra B.D. Mediated biosensors, Biosens Bioelectron, 2002; 17:441-456. DOI:10.1016/S0956-5663(01)00313-X
3. 3. Freire R.S., Pessoa C.A., Mello L.D., Kubota L.T. Direct electron transfer:An approach for electrochemical biosensors with higher selectivity and sensitivity, J Braz Chem Soc, 2003; 14:230-243. http://jbcs.sbq.org.br/imageBank/PDF/v14n2a08.pdf
4. 4. Wang J. Electrochemical glucose biosensors, Chem Rev, 2008;108:814-825. DOI:10.1021/cr068123a
5. 5. Collinson M.M. Analytical applications of organically modified silicates, Mikrochim Acta, 1998; 129:149-165. DOI:10.1007/BF01244737
6. 6. Jin W, Brennan J.D., Properties and application of proteins encapsulated within sol-gel derived materials, Anal Chim Acta, 2002;461:1-36. DOI:10.1016/S0003-2670(02)00229-5
7. 7. Thenmozhi K, Narayanan S.S. Electrochemical sensor for H2O2 based on thionin immobilized 3-aminopropyltrimethoxy silane derived sol-gel thin film electrode, Sens Actuators B, 2007; 125:195-201. DOI:10.1016/j.snb.2007.02.006
8. 8. Tu Y.F., Di J.W., Chen X.J. Study of the nano-size silica sol-gel film as the matrix of chemically modified electrode, J Sol-Gel Sci Technol, 2005;33:187-191. DOI:10.1007/s10971-005-5613-6

9. 9. Pandey P.C., Upadhyay S, Pathak, H.C. A new glucose sensor based on encapsulated glucose oxidase within organically modified sol-gel glass, Sens Actuators B, 1999;60:83-89. DOI:10.1016/S0925-4005(99)00246-4
10. 10. Pauliukaite R, Brett C.M.A. Characterization of novel glucose oxysilane sol-gel electrochemical biosensors with copper hexacynoferrate mediator, Electrochim Acta, 2005;50:4973-4980. DOI:10.1016/j.electacta.2005.01.060
11. 11. Demirkıran N, Ekinci E. Immobilization of glucose oxidase in GLYMO/MTEOS sol-gel film for glucose biosensor application, Acta Chim Slov, 2012; 59:302-306. http://acta-arhiv.chem-soc.si/59/59-2-302.pdf