A colorimetric assay for immobilized chloroperoxidase

Area of Science:

• Biochemistry
• Enzyme kinetics
• Analytical chemistry

Background:

• Chloroperoxidase (CPO) is an important enzyme involved in various biological processes.
• Accurate and sensitive methods are needed for quantifying CPO activity.
• Existing assays may lack speed, sensitivity, or applicability to immobilized enzymes.

Purpose of the Study:

• To develop a rapid and sensitive colorimetric assay for chloroperoxidase activity.
• To identify an optimal chromogenic substrate for CPO detection.
• To validate the assay for both soluble and immobilized CPO.

Main Methods:

• Screened four chromogenic substrates for CPO-catalyzed color production.
• Selected N,N,N',N'-Tetramethyl-p-phenylenediamine based on high molar absorption of the blue product.
• Optimized assay conditions including wavelength (563 nm) and product stabilization.
• Determined the linear range of the assay with respect to enzyme concentration.
• Tested the assay with both soluble and immobilized CPO.

Main Results:

• N,N,N',N'-Tetramethyl-p-phenylenediamine yielded a blue product with absorbance maxima at 563 and 610 nm.
• The assay demonstrated high sensitivity and a stable product absorbance for at least 1 hour.
• A linear relationship was established between enzyme amount and product absorbance.
• The assay proved effective for both soluble and immobilized chloroperoxidase.

Conclusions:

• A robust and sensitive colorimetric assay for chloroperoxidase activity has been successfully developed.
• The assay utilizes N,N,N',N'-Tetramethyl-p-phenylenediamine as an effective chromogenic substrate.
• This method is suitable for quantifying chloroperoxidase activity in both soluble and immobilized forms, enhancing its applicability in research and diagnostics.