A microfluidic point-of-care bilirubin measurement system.

Measuring bilirubin levels in blood or serum is a critical process for evaluating liver function and monitoring the effectiveness of various treatments for liver-related conditions. Abnormal bilirubin levels can indicate liver dysfunction, bile duct obstruction, or hemolytic disorders, making accurate measurement essential for timely diagnosis and intervention. This study focuses on assessing the clinical performance of a newly developed point-of-care (PoC) device specifically designed for rapid and reliable bilirubin measurement in serum samples. The PoC device integrates advanced technology, including a compact optoelectronic sensing module, which provides high sensitivity and precision, and a microfluidic test cartridge, enabling efficient sample handling and analysis.

To validate the performance of the PoC device, serum bilirubin levels were measured in 20 patient samples, covering a wide concentration range from 2 µmol/L to 480 µmol/L. These measurements were compared with those obtained using the standard laboratory method, which serves as the gold standard in clinical diagnostics. Statistical methods, including Bland–Altman analysis and Passing–Bablok regression, were employed to evaluate the agreement and correlation between the PoC device and standard laboratory results. Additionally, the diagnostic capability of the PoC device to classify samples based on clinically relevant bilirubin thresholds—specifically 200 µmol/L, 300 µmol/L, and 450 µmol/L—was assessed using receiver operating characteristic (ROC) analysis.

The results demonstrated that the PoC device produced measurements with a mean difference of -5.6 µmol/L compared to the standard laboratory method. The 95% confidence interval for this difference ranged from -45.1 µmol/L to 33.9 µmol/L, indicating acceptable limits of agreement for clinical use. Furthermore, the coefficient of determination (R²) between the two methods was 0.986, reflecting a strong correlation. The PoC device also exhibited robust diagnostic performance, achieving over 90% sensitivity and 97% specificity for correctly classifying bilirubin levels within the defined clinical thresholds. These findings highlight the potential of the PoC device as a reliable alternative to traditional laboratory methods, particularly in settings where rapid and on-site testing is required.

In conclusion, this study demonstrates that the proposed PoC device is capable of accurately measuring serum bilirubin levels with clinically acceptable precision and reliability. Its compact design, integration of advanced technologies, and high diagnostic accuracy make it a valuable tool for point-of-care applications in various healthcare settings. The device’s ability to provide quick and accurate results has the potential to improve patient outcomes by enabling timely clinical decision-making, especially in resource-limited environments or emergency care scenarios.