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Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth

Organized by Chemical Engineering Department, Gadjah Mada University, 4th - 5th December 2007 at Yogyakarta, Indonesia.

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Bibliographic Details
Main Authors: Mohd Noor Ahmad, Kwan, Wei Yen, A.K.M. Shafiqul Islam, Zhari Ismail, Misni Surif
Format: Working Paper
Language:English
Published: Gadjah Mada University 2008
Subjects:
Orthosiphon stamineus benth
Xanthine oxidase
Biosensors
Chitosan
Antioxidants
Herbal tea
Online Access:http://dspace.unimap.edu.my/xmlui/handle/123456789/2638
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id my.unimap-2638
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spelling my.unimap-26382009-12-31T04:06:51Z Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth Mohd Noor Ahmad Kwan, Wei Yen A.K.M. Shafiqul Islam Zhari Ismail Misni Surif Orthosiphon stamineus benth Xanthine oxidase Biosensors Chitosan Antioxidants Herbal tea Organized by Chemical Engineering Department, Gadjah Mada University, 4th - 5th December 2007 at Yogyakarta, Indonesia. An amperometric biosensor has been developed using xanthine oxidase (XO) enzyme as sensing materia] for the determination of antioxidant property of Orthosiphon stamineus benth (Cat whiskers) extracts. The enzyme was physically entrapped in modified chitosan membrane on carbon paste electrode. Experimental variables concerning the biosensor preparation such as the effect of enzyme amount, chitosan pH, pH of working buffer were optimized. The sensor showed linear response towards xanthine (poised at +600mV vs. Ag/AgCl) between 5.0 x 10ֿ7M to 43 x 10ֿ5M at pH 7.0 with detection limit of (S/N=3) of 1.5 x 10 ֿ7M. The biosensor reached 95% of it's steady-state current at about 6 seconds. The usefulness of the biosensor for the herbal extracts was demonstrated by determining percentage of inhibition of Orthosiphon stamineus extracts and compared with the method reported earlier by Tadataka Noro et al. using the uv-vis spectrophotometry. 2008-10-29T07:33:28Z 2008-10-29T07:33:28Z 2007-12-05 Working Paper http://hdl.handle.net/123456789/2638 en Proceedings of the 14th Regional Symposium on Chemical Engineering 2007 Gadjah Mada University
institution Universiti Malaysia Perlis
building UniMAP Library
collection Institutional Repository
continent Asia
country Malaysia
content_provider Universiti Malaysia Perlis
content_source UniMAP Library Digital Repository
url_provider http://dspace.unimap.edu.my/
language English
topic Orthosiphon stamineus benth
Xanthine oxidase
Biosensors
Chitosan
Antioxidants
Herbal tea
spellingShingle Orthosiphon stamineus benth
Xanthine oxidase
Biosensors
Chitosan
Antioxidants
Herbal tea
Mohd Noor Ahmad
Kwan, Wei Yen
A.K.M. Shafiqul Islam
Zhari Ismail
Misni Surif
Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth
description Organized by Chemical Engineering Department, Gadjah Mada University, 4th - 5th December 2007 at Yogyakarta, Indonesia.
format Working Paper
author Mohd Noor Ahmad
Kwan, Wei Yen
A.K.M. Shafiqul Islam
Zhari Ismail
Misni Surif
author_facet Mohd Noor Ahmad
Kwan, Wei Yen
A.K.M. Shafiqul Islam
Zhari Ismail
Misni Surif
author_sort Mohd Noor Ahmad
title Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth
title_short Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth
title_full Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth
title_fullStr Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth
title_full_unstemmed Biosensor for antioxidant determination in herbal tea, Orthosiphon stamineus benth
title_sort biosensor for antioxidant determination in herbal tea, orthosiphon stamineus benth
publisher Gadjah Mada University
publishDate 2008
url http://dspace.unimap.edu.my/xmlui/handle/123456789/2638
_version_ 1643787705475137536
score 13.214268

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