Direct detection of renal function markers using microchip CE with pulsed electrochemical detection

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Clinical Diagnostics

Background:

• Traditional assays for creatinine, creatine, and uric acid often rely on enzymes or chemical reactions.
• Electrophoretic microchips offer potential for integrated, portable, and rapid separation and detection.
• Assessing renal function commonly involves measuring these key biomarkers.

Purpose of the Study:

• To develop a microchip capillary electrophoresis (CE) system for direct detection of creatinine, creatine, and uric acid.
• To utilize pulsed amperometric detection (PAD) for sensitive measurement of these nitrogen-containing and oxidizable compounds.
• To validate the system's performance for clinical applications, including real urine sample analysis.

Main Methods:

• Development of a microchip CE system.
• Implementation of pulsed amperometric detection (PAD).
• Optimization of separation conditions using a borate buffer (30 mM, pH 9.4).
• Analysis of creatinine, creatine, and uric acid in a real urine sample.

Main Results:

• Achieved baseline separation of the three compounds in under 200 seconds.
• Established linear calibration curves with low limits of detection (80 µM for creatinine, 250 µM for creatine, 270 µM for uric acid).
• Demonstrated successful analysis of a real urine sample, with creatinine results validated against a clinical assay kit.

Conclusions:

• The developed microchip CE-PAD system provides a fast, sensitive, and portable method for simultaneous detection of creatinine, creatine, and uric acid.
• This technology holds promise for improving the efficiency and accessibility of clinical diagnostics, particularly for renal function assessment.
• The system's performance in analyzing real urine samples indicates its potential for practical clinical use.