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Portugaliae Electrochimica Acta

Print version ISSN 0872-1904

Port. Electrochim. Acta vol.21 no.2 Coimbra  2003

 

Development of a New Amperometric Biosensor for Lactose Determination

 

R.J.M. Lourenço, M.L.M. Serralheiro, M.J.F. Rebeloa) *

Centro de Estudos Bioquímicos e Fisiologia Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal

a) Centro de Electroquímica e Cinética, Faculdade de Ciências da Universidade de Lisboa, 1749-016 Lisboa, Portugal

 

Received 20 December 2002; accepted in revised form 25 February 2003

 

Abstract

A new amperometric biosensor for lactose determinaion in raw milk was developed through the simultaneous immobilization of β-galactosidase and galactose oxidase on a derivatised polyethersulphone membrane. β-galactosidase catalyses the hydrolysis of lactose into galactose and glucose and galactose oxidase catalyses the oxidation of galactose into galactonic acid and H2O2. The membranes with the two immobilized enzymes were then used in an amperometric sensor, by oxidation of the H2O2 formed, at a Pt electrode of an Universal Sensors electrode base system. The sensitivity and the reproducibility of the biosensor thus formed were found to be 6.81 and 0.72 nA.M-1, respectively. Biosensors were found to be stable for 20 days.

Keywords: biosensor, lactose, amperometric, stabilization, b-galactosidase, galactose oxidase.

 

Texto completo disponível apenas em PDF.

Full text only available in PDF format.

 

References

1. J.G. Zadow. Lactose Properties and Uses. J. Dairy Science 67 (1984) 2654-2679.        [ Links ]

2. A.B. Karasz, W.M. Gautenbei, L. Bokns. Determination of Added Lactose (Nonfat Dry Milk) in Meat Products. I. Colorimetric Method. J. Assoc. Off. Anal. Chem. 54 (1971) 1436-1438.        [ Links ]

3. R.K. Bahl. An Enzymatic Method for the Determination of Lactose in Milk Including Human Milk. Analyst 97 (1972) 559-561.        [ Links ]

4. V.V. Mistry, H.N. Hassan, R.J. Baer. Spectrophotometric Method for Measurement of Lactose in Milk and Milk Products by Using Dialysis. J. Assoc. Off Anal. Chem. 72-6 (1989) 877-880.         [ Links ]

5. R. Pilloton, M. Mascini, L.G. Casella, M.R. Festa, E. Mottari. Lactose determination in raw milk with a two enzymes based electrochemical sensor. Anal. Lett. 20 (1987) 1803.        [ Links ]

6. J.A. Hamid, G.J. Moody, J.D.R. Thomas. Flow-through Multi-enzyme Electrodes for the Determination of Lactose. Analyst 114 (1989) 1587-1592.        [ Links ]

7. R. Puchades, A. Maquieira, L. Torró. Enzymatic Flow Injection Determination of Lactose in Milk With On-line Dialysis. Analyst 118 (1993) 855-859.        [ Links ]

8. A. Jäger, U. Bilitewski. Screen-printed Enzyme Electrode for the Determination of Lactose. Analyst 119 (1994) 1251-1255.        [ Links ]

9. I. Eshkenazi, E. Maltz, B. Zion, J. Rishpon. A Three-Cascaded-Enzymes Biosensor to Determine lactose Concentration in Raw Milk. J. Daily Science 83 (2000) 1939-1945.        [ Links ]

10. J. Tkáč, P. Šturdik. Rapid and sensitive galactose oxidase-peroxidase biosensor for galactose detection with prolonged stability. Biotechnology Techniques 13 (1999) 931-936.        [ Links ]

11. L. Tkáč, E. Šturdík, P. Gemeiner. Novel glucose on-interference biosensor for lactose detection based on galactose oxidase-peroxidase with and without co-immobilised β-galactosidase. Analyst 125 (2000) 1285-1289.        [ Links ]

12. H. Gülce, A. Gülce, A. Yildiz. A Novel Two-Enzyme Amperometric Electrode for Lactose Determination. Analytical Sciences 18 (2002) 147-150.        [ Links ]

13. J. Švorc, S. Miertuš, A. Barlíková. Hybrid Biosensor for determination of Lactose. Anal. Chem. 62 (1990) 1628-1631.        [ Links ]

14. P.V. Climent, M.L.M. Serralheiro, M.J.F. Rebelo. Development of a new amperometric biosensor based on polyphenoloxidase and polyethersulphone membrane. Pure Appl. Chem. 73-12 (2001) 1993-1999.        [ Links ]

 

* Corresponding author. E-mail address: mjrebelo@fc.ul.pt. Communication presented at XV Ibero-American Meeting of Electrochemistry.

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