Multichannel separation device with parallel electrochemical detection.

Area of Science:

• Analytical Chemistry
• Materials Science
• Biomedical Engineering

Background:

• Simultaneous analysis of multiple analytes is crucial for complex biological samples.
• 3D printing offers novel possibilities for microfluidic device fabrication.
• Titanium is a biocompatible and robust material for device construction.

Purpose of the Study:

• To design and fabricate a multi-channel 3D-printed device for simultaneous sample analysis.
• To develop and optimize monolithic stationary phases for reversed-phase and hydrophilic interaction chromatography.
• To validate the device's performance in analyzing dopamine precursors and metabolites in human urine.

Main Methods:

• Device fabrication using 3D printing with titanium.
• Preparation of monolithic stationary phases with zwitterionic monomers and dimethacrylate cross-linkers.
• Optimization of mobile phase composition using window diagrams.
• Integration of miniaturized electrochemical detectors with carbon fiber electrodes.
• Method validation using a three-parameter retention model and human urine samples.

Main Results:

• A four-channel parallel analysis device was successfully manufactured.
• Stationary phases exhibited dual retention mechanisms (reversed-phase and HILIC).
• Optimized mobile phase achieved high resolution for dopamine-related compounds.
• Simultaneous analysis and detection of dopamine in human urine were demonstrated.
• Experimental results correlated well with the retention model predictions.

Conclusions:

• The 3D-printed titanium device enables efficient, simultaneous chromatographic separations.
• The developed monolithic stationary phases are versatile for analyzing dopamine and its metabolites.
• This technology shows significant potential for rapid and accurate analysis of biological samples.