ZnS quantum dots as pH probes for study of enzyme reaction kinetics.

Abstract:

:Water soluble ZnS quantum dots (QDs) modified by mercaptoacetic acid (MAA) were used to determinate proton concentration in aqueous solutions by fluorescence spectroscopic technique. The results showed that the fluorescence of the water-soluble QDs could be quenched by proton concentration and the fluorescence intensity of the water-soluble QDs decreased linearly as the pH varied from 4.5 to 7.0. Based on this phenomenon, a convenient, rapid and specific method to determine of enzyme reaction kinetics was proposed. The modified ZnS QDs were successfully used as pH probes in monitoring the hydrolysis of glycidyl butyrate catalyzed by porcine pancreatic lipase (PPL). The proposed method was found to improve stability, sensitivity and a monitoring range for determination proton concentration as compared to the already described analytical methods based on p-Nitrophenoxide (PNP).

journal_name

Enzyme Microb Technol

authors

Wu D,Chen Z

doi

10.1016/j.enzmictec.2012.03.012

subject

Has Abstract

pub_date

2012-06-10 00:00:00

pages

47-52

issue

1

eissn

0141-0229

issn

1879-0909

pii

S0141-0229(12)00043-9

journal_volume

51

pub_type

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