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Fluorescence decrease of conjugated polymers by the catalytic activity of horseradish peroxidase and its application
M I González-Sánchez1, M Laurenti, J Rubio-Retama
1Physical Chemistry Department, School of Industrial Engineering, University of Castilla-La Mancha, Albacete 02071, Spain.
Biomacromolecules
|February 24, 2011
Summary
Horseradish peroxidase (HRP) catalyzes the fluorescence decrease of a conjugated polymer (MPS-PPV) and acetaminophen. Encapsulating HRP in microgels enables detection of phenolic compounds via fluorescence changes.
Area of Science:
- Biochemistry and Enzymology
- Polymer Science
- Analytical Chemistry
Background:
- Horseradish peroxidase (HRP) is a versatile enzyme with diverse catalytic applications.
- Conjugated polymers like poly(2-methoxy-5-propyloxy sulfonate phenylene vinylene) (MPS-PPV) exhibit fluorescence sensitive to their environment.
- The interaction between enzymes and fluorescent polymers can be exploited for sensing applications.
Purpose of the Study:
- To investigate the fluorescence quenching of MPS-PPV mediated by horseradish peroxidase.
- To explore the potential of MPS-PPV as a substrate in HRP-catalyzed reactions.
- To develop a sensing system for phenolic compounds using HRP and MPS-PPV.
Main Methods:
- Studied the fluorescence decrease of MPS-PPV in the presence of HRP and hydrogen peroxide (H2O2).
- Investigated the effect of acetaminophen, a phenolic drug, on the fluorescence quenching.
- Encapsulated HRP within polyacrylamide microgels to isolate enzymatic intermediates and study the reaction pathway.
Main Results:
- MPS-PPV fluorescence decreased due to electron transfer to HRP intermediates (compounds I and II) during its catalytic cycle.
- Acetaminophen addition enhanced the fluorescence decrease, indicating co-oxidation of MPS-PPV and acetaminophen.
- HRP encapsulation in microgels allowed for selective detection of acetaminophen oxidation products through fluorescence changes.
Conclusions:
- MPS-PPV serves as a donor substrate for HRP, leading to fluorescence quenching.
- The HRP-MPS-PPV system demonstrates potential for detecting phenolic compounds like acetaminophen.
- Microgel encapsulation of HRP offers a strategy to control enzymatic reactions and enhance sensing specificity.
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