A smartphone-based calibration-free portable urinalysis device

As one of the most common medical diagnosis methods, urinalysis is a highly demanded technique for screening tests or daily monitoring of various diseases. With the rapid development of POC (point-of-care) systems, a convenient house-using urinalysis device is widely needed. However, considering the difference of onboard systems and multiple test indicators in urinalysis, the design of such an intelligent device is still challenging. In this paper, a smartphone-based portable urinalysis system has been developed and applied for the colorimetric analysis of routine urine examination indices using an Android app. By integrating the test paper sensor in the portable device for urinalysis, our system significantly improves the instability of conventional dipstick-based manual colorimetry, and the smartphone application used for color discrimination enhances the accuracy of the visual assessment of sample strips. Using a simple operation approach that takes ∼ 2 min per test, our system can be applied as rapid urinalysis for routine check-ups.