Recent advances in nephropathy biomarker detections using paper-based analytical devices

Nephropathy or kidney disease involves the deterioration of kidney functions, causing severe diseases, such as proteinuria, chronic kidney diseases, and kidney failure. Currently, nephropathy that develops into kidney failure is increasing globally, as indicated by the increasing number of patients undergoing hemodialysis. Some developed analytical methods for nephropathy using albumin, creatinine, uric acid, and the urinary albumin-to-creatine ratio biomarkers, including spectrophotometry, turbidimetric immunoassay, and ELISA, have been reported so far, providing good accuracy and precision. However, WHO has established guidelines for developing diagnostic tools that meet several criteria: Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, Delivered to those who need it. This means that nephropathy detection can be carried out using a simple method compatible with point-of-care that allows independent urine analysis by patients. For this purpose, the use of paper-based analytical devices (PADs) as an alternative platform for the detection of albumin, creatinine, uric acid, and the urinary albumin-to-creatine ratio were reviewed.