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Measurement of serum phosphate levels using a mobile sensor
Aniruddha Ray1, Sarah Esparza2, Dimei Wu2
1Department of Electrical and Computer Engineering, University of California, Los Angeles, CA 90095, USA. ozcan@ucla.edu and Department of Bioengineering, University of California, Los Angeles, CA 90095, USA and California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA and Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA. isalusky@mednet.ucla.edu and Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606, USA.
A new portable device accurately measures serum phosphate levels from a single blood drop. This cost-effective, smartphone-integrated sensor offers frequent monitoring for chronic kidney disease patients.
Area of Science:
- Biomedical Engineering
- Clinical Chemistry
- Medical Diagnostics
Background:
- Serum phosphate monitoring is vital for advanced chronic kidney disease (CKD) and dialysis patients.
- Current monitoring is infrequent (0.5-3 months) due to clinic visit limitations and costs.
- Abnormal phosphate levels pose significant health risks for these patient populations.
Purpose of the Study:
- To develop a portable, cost-effective point-of-care device for serum phosphate measurement.
- To enable frequent or daily monitoring of serum phosphate levels.
- To provide a user-friendly and accessible diagnostic tool for CKD patients.
Main Methods:
- Integration of a paper-based microfluidic platform with a custom smartphone reader.
- Development of a 3D-printed smartphone attachment (under $80 USD).
- Testing the device on hemodialysis patients using small whole blood samples (<60 μl).
Main Results:
- The device achieved strong correlation with laboratory tests (Pearson r = 0.95, p < 0.001).
- Disposable test material cost is under $3.5 USD.
- Point-of-care measurement is completed in approximately 45 minutes.
Conclusions:
- The developed mobile sensor is a low-cost, portable, and accurate solution for serum phosphate monitoring.
- This system has the potential for daily use by patients at home, improving CKD management.
- Facilitates timely intervention by enabling frequent phosphate level assessment.
