Ion concentration measurement using synthetic microfluidic papers.

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Point-of-Care Diagnostics

Background:

• Non-invasive self-health evaluation using biological fluids like urine and saliva is desirable.
• Accurate diagnostic results depend on precise biological liquid sampling.
• Conventional filter paper methods exhibit variations in sampling volume due to structural differences.

Purpose of the Study:

• To develop and validate synthetic microfluidic papers for precise biological liquid sampling.
• To optimize the design and collection method for accurate sample volume acquisition.
• To demonstrate the utility of synthetic microfluidic papers in quantifying analyte concentrations.

Main Methods:

• Synthetic microfluidic papers composed of obliquely combined micropillars were designed and fabricated.
• Sampling volume accuracy was evaluated using various designs and collection techniques.
• Potassium concentration was measured using optimized synthetic microfluidic paper and a densitometer.

Main Results:

• Synthetic microfluidic papers demonstrated improved sampling volume accuracy compared to conventional methods.
• An optimized protocol was established for precise liquid collection.
• Accurate potassium concentration measurements validated the effectiveness of the synthetic microfluidic papers.

Conclusions:

• Synthetic microfluidic papers offer a precise and reliable method for biological liquid sampling.
• This technology enhances the accuracy of non-invasive diagnostic tests.
• The developed method holds significant potential for self-health monitoring applications.