Elsevier

Biosensors and Bioelectronics

Volume 23, Issue 3, 31 October 2007, Pages 432-437
Biosensors and Bioelectronics

Short communication
Electrochemical study of ferrocenemethanol-modified layered double hydroxides composite matrix: Application to glucose amperometric biosensor

https://doi.org/10.1016/j.bios.2007.06.007Get rights and content

Abstract

A novel amperometric glucose sensor based on co-immobilization of ferrocenemethanol (MeOHFc) and glucose oxidase (GOD) in the layered double hydroxides (LDHs) was described. MeOHFc immobilized in LDHs played effectively the role of an electron shuttle and allowed the detection of glucose at 0.25 V (versus SCE), with dramatically reduced interference from easily oxidizable constituents. The sensor (LDHs/MeOHFc/GOD) exhibited a relatively fast response (response time was about 5 s), low detection limit (3 μM), and high sensitivity (ca. 60 mA M−1 cm−2) with a linear range of 6.7 × 10−6 to 3.86 × 10−4 M of glucose. Apparent Michaelis–Menten constant was calculated to be 2.25 mM.

Introduction

Since the first report by Clark and Lyons (1962), biosensors have been received the considerable attention. In the literature, there are thousands of reports on biosensors based on glucose oxidase (GOD), because this enzyme is well-studied, inexpensive, stable and particularly applied in clinical and chemical analysis (Cheetham and Wiseman, 1985). Nevertheless, significant efforts should be continuously devoted to the production of reliable glucose sensors, due to the great demand for blood glucose measurements (particularly for treatment and control of diabetes). The development of amperometric glucose biosensors has included several techniques for immobilization of glucose oxidase onto electrodes. Selection and modification of the immobilization matrix are the essential parameters for optimization of enzyme stability and overall sensitivity (Cosnier, 1999).

Inorganic clay has been widely utilized to the biosensor constructions by the group of Cosnier (Poyard et al., 1998, Cosnier et al., 2000, De Melo et al., 2002, Shan et al., 2002) and that of Walcarius (Tonlé et al., 2004, Tonlé et al., 2005, Mbouguen et al., 2006, Ngameni et al., 2006, Tchinda et al., 2007). Layered double hydroxides (LDHs), also called “anionic clays”, have been demonstrated as attractive materials due to their technological importance in catalysis, separation, optics, medical science and nanocomposite materials engineering (Choy et al., 1999, Luis Garcia-Ponce et al., 2000, Crepaldi et al., 2000). LDHs consist of positively charged metal hydroxide layers, in which the anions (along with water) are stabilized in order to compensate the positive layer charges. In our previous works, we showed that these synthetic lamellar materials could be used as immobilization matrix of enzymes for biosensor applications (De Melo et al., 2002, Shan et al., 2003a, Shan et al., 2003b, Shan et al., 2004a, Shan et al., 2004b, Shan et al., 2006a).

Very recently, we reported a cheap and simple amperometric biosensor, based on the immobilization of GOD into LDHs ([Zn3–Al–Cl]) (Shan et al., 2006a). The resulting glucose sensor exhibited good analytical performance, such as rapid response, good operational stability and low detection limit. No significant effect was observed at the low concentration ratio of interferents to glucose with such an unmediated sensor at the applied potential of 0.6 V versus SCE. However, with increase in the interferents–glucose ratio, the interference became more and more observable.

Mediated enzyme electrodes are known to be less susceptible to interfering substances because of lower electrode potentials (Chaubey and Malhotra, 2002). Sensors in which the mediators are co-immobilized with the enzymes on the electrodes will not require the addition of the former to the test solutions (‘reagentless’), thereby eliminating many practical limitations. The immobilized mediators catalyze the redox reactions of biomolecules and shuttle the electrons more efficiently between enzymes and the base electrodes, resulting in the greatly enhanced sensing performance (Niu and Lee, 2002). With the aim to improve the analytical performances of the LDHs modified biosensors, especially their selectivity, in this present work, GOD enzyme and ferrocenemethanol (MeOHFc) mediators were co-immobilized in LDHs membranes to form reagentless glucose biosensors.

Section snippets

Reagents

Glucose oxidase (GOD) (EC1.1.3.4, Type VII-S, 108 U/mg) from Aspergillus niger was purchased from Amresco. Ferrocenemethanol (MeOHFc) was obtained from Sigma. Layered double hydroxides (LDHs) Zn3Al(OH)8Cl, denoted [Zn3–Al–Cl] was synthesized by co-precipitation method developed by De Roy (Shan et al., 2006a, De Roy et al., 1992). The colloidal suspension of LDHs was prepared in deionized and decarbonated water. Other aqueous solutions were prepared in deionized distilled water. Fifty millimolar

Results and discussion

The use of artificial electron mediators to shuttle electrons from the redox center of the enzyme to the surface of the working electrode can effectively reduce the operating potential and hence enhance selectivity and sensitivity. There are several reports on MeOHFc mediated biosensor (Setti et al., 2005, Piro et al., 2001, Zhang et al., 2004a). However, MeOHFc was generally added directly into the test solution, which results in many application problems. In this work, MeOHFc was immobilized

Conclusion

In this work, we gave the first successful example to immobilize simultaneously enzyme and mediator in the anionic clay LDHs. MeOHFc was only absorbed on the external phase of the LDHs particles. From the cyclic voltammetry and amperometric measurements, the entrapped MeOHFc was demonstrated to be redox active and function as electron shuttling agent between GOD and electrode. In our future work, we attempt to intercalate MeOHFc or other ferrocene derivates into the interlayers of LDHs by the

Acknowledgments

The authors are grateful to the financial supports of National Natural Science Foundation of China (Grant no. 20505014), the Key Project of Chinese Ministry of Education (no. 207041) and the Foundation of Jiangsu Provincial Key Program of Physical Chemistry in Yangzhou University.

References (42)

  • W.A. Alves et al.

    Biosens. Bioelectron.

    (2006)
  • R.S. Brown et al.

    Anal. Chim. Acta

    (1995)
  • A. Chaubey et al.

    Biosens. Bioelectron.

    (2002)
  • S. Cosnier

    Biosens. Bioelectron.

    (1999)
  • M.E. Ghica et al.

    Anal. Chim. Acta

    (2005)
  • S.H. Lee et al.

    Sens. Actuator B

    (2006)
  • J. Li et al.

    J. Electroanal. Chem.

    (1999)
  • J. Niu et al.

    Sens. Actuator B

    (2002)
  • R. Pauliukaite et al.

    Electrochim. Acta

    (2006)
  • B. Piro et al.

    J. Electroanal. Chem.

    (2001)
  • S. Poyard et al.

    Anal. Chim. Acta

    (1998)
  • L. Setti et al.

    Biosens. Bioelectron.

    (2005)
  • D. Shan et al.

    J. Electroanal. Chem.

    (2002)
  • D. Shan et al.

    Biosens. Bioelectron.

    (2004)
  • D. Shan et al.

    Anal. Biochem.

    (2006)
  • A.J. Tchinda et al.

    Sens. Actuator B

    (2007)
  • I.K. Tonlé et al.

    Electrochim. Acta

    (2004)
  • I.K. Tonlé et al.

    Sens. Actuator B

    (2005)
  • K. Wang et al.

    Biosens. Bioelectron.

    (2005)
  • J. Yu et al.

    Biosens. Bioelectron.

    (2003)
  • S. Zhang et al.

    Anal. Chim. Acta

    (2004)
  • Cited by (0)

    View full text