INVESTIGATING BIOMARKERS IN TEAR FLUID FOR RAPID DIAGNOSIS OF DIABETIC RETINOPATHY USING SINGLE MODE OPTICAL FIBER BIOSENSOR

Abstract

Diabetic retinopathy is one of the most prevalent and the most distinct complication of diabetic mellitus, which is estimated to affect 700 million people globally by 2045. Previous studies have shown that about 14% of patients with type 1 and 33% of patients with type 2 diabetes progress to develop diabetic retinopathy. This shows the ultimate need for quick, effective, and affordable screening of diabetic retinopathy for early intervention. Besides the high purchase cost, existing technologies used for screening diabetic retinopathy using tear fluid have registered significant challenges due to the limited volume accessible for analysis; the collection of tear fluid from patients; and the tedious laboratory processing for a timely diagnosis. Optical fiber biosensors have transformed biosensing platforms by bringing added benefits which include simplicity of fabrication and operation, low-cost, rapid response time, miniaturized size, high sensitivity and specificity, robustness, in-situ measurement capability, and can easily be interfaced for data analysis, making them ideal for a very wide range of applications. The proposed study uses fiber optic biosensors as affinity biosensors to detect LCN-1 protein spiked in artificial tear fluid using a wearable eye-goggle tear fluid sampling device that facilitates the interaction of tear fluid sample with an optical fiber ball resonator (OFBR) biosensor. This study aims to prove this concept and eliminate the inconsistencies in existing sample collection, storage, and laborious processing methods currently being used in conventional tear fluid analysis. The experiments involved evaluating static and in-situ measurements of LCN-1 protein in artificial tears using a wearable sampling device. Results obtained from this experiment has demonstrated the potential of using the proposed concept for detecting biomarker in tear fluid using single-mode fiber optic biosensor.