H-point curve isolation method for determination of catechol in complex unknown mixtures

Area of Science:

• Analytical Chemistry
• Spectrophotometry
• Chemometrics

Background:

• Catechol determination is challenging due to interfering phenolic compounds.
• Existing spectrophotometric methods struggle with complex matrices and overlapping spectra.
• Accurate quantification of catechol is crucial in various applications, including environmental and biological sample analysis.

Purpose of the Study:

• To develop and validate a novel spectrophotometric method for accurate catechol determination.
• To address the challenge of quantifying catechol in the presence of significant phenolic interferents.
• To demonstrate the method's applicability to both simulated and real-world complex samples.

Main Methods:

• Combination of H-point curve isolation method (HPCIM) and H-point standard additions method (HPSAM).
• Spectrophotometric multivariate calibration using successive standard additions.
• Extraction of cumulative interferent spectra using HPCIM for subsequent HPSAM analysis.

Main Results:

• The HPCIM effectively extracted cumulative interferent spectra, validated with simulated data.
• The combined HPCIM-HPSAM method accurately determined catechol in synthetic ternary mixtures with overlapping interferents.
• Successful application to real samples (tea and urine) yielded percent recoveries between 95.4% and 113.6%.

Conclusions:

• The proposed HPCIM-HPSAM method offers a robust solution for catechol quantification in complex matrices.
• This approach effectively overcomes spectral interferences from phenolic compounds.
• The method demonstrates high accuracy and applicability for real-world sample analysis.