Clinically Deployable 3D Cascade-Based Sensing
Device for Diagnosing Kidney Disease

Chronic kidney disease (CKD) has emerged as a significant contributor to morbidity and mortality in the 21st century. A bioengineered paper device has been created for the purpose of quantifying albumin in physiological samples. The paper surface was activated, and antibodies that are specific to the targeted biomarker were immobilized on the modified paper surface. Following the change, each subsequent step was characterized using FTIR, XPS, SPM, and optical analysis. Additionally, the device model was created via CAD files, and a three-dimensional cascade device was manufactured with an integrated continuous light source in order to establish a suitable and regulated environment for picture processing. Following the introduction of the sample onto the bioengineered paper, the subsequent occurrence involves the antigen–antibody reaction. The study of the image involved the utilization of an optical method, which entailed the identification of the image's area and the intensity of its color. The developed immunosensor's linear dynamic range has been reported to be 1–60 mg/mL, with a detection limit of 0.049(±0.002) mg/mL, spanning both the clinical and normal range of albumin in physiological samples. Furthermore, an assessment was conducted to determine the specificity of the immunosensor toward various compounds present in serum. The outcomes of this evaluation demonstrated a low level of cross-reactivity and a high level of performance. The device exhibited high precision and accuracy in determining the levels of albumin in the serum sample with the recovery % being between 88.14 and 97.70. The developed device has the potential to be employed in primary health care centers.