Boron nitride quantum dot-enabled paper microfluidic platform for non-invasive kidney disease detection

Abstract

Chronic kidney disease (CKD) is a significant disorder that requires reliable and non-invasive tracking of key urinary biomarkers like creatinine, albumin, and urea for early diagnosis and disease management. In the present work, a microfluidic paper-based analytical device integrated with boron nitride quantum dots (BNQDs) was developed for the detection of these biomarkers according to fluorescence response. The fluorescence response of BNQDs was optimized at pH 8, BNQD concentration of 3.6 mM, and an incubation time of 10 min. Under these optimized conditions, concentration-dependent fluorescence quenching was observed with no emission peak shift at ~498 nm. On the other hand, linear detection ranges of 1.0 to 5.0 mg/mL for creatinine (R² = 0.9626), 0.06 to 0.20 mg/mL for albumin (R² = 0.974), and 0.2 to 1.0 mg/mL for urea (R² = 0.9844) were obtained. The developed system in this study was successfully tested using the artificial urine samples, providing recoveries of 95–105%. The proposed BNQD-enabled microfluidic paper-based platform provides the simultaneous fluorescence detection of creatinine, albumin, and urea, three clinically relevant biomarkers associated with CKD, demonstrating its potential as a simple, low-cost, and multiplex point-of-care (POC) sensing platform.