Pre-eclampsia diagnosis on clinical samples using microfiber-Bragg-grating-assisted point-of-care biosensor

Pre-eclampsia is a severe multi-organ complication that can arise during pregnancy, posing a serious threat to both the mother and the infant. Early diagnosis and treatments are crucial to improve patient outcomes. Existing diagnostic approaches are often time-consuming, and require specialized equipment. Placental growth factor (PlGF), a key biomarker for the pre-eclampsia diagnosis, undergoes a decrease in affected patients. Therefore, we propose an innovative microfiber Bragg grating (μFBG) assisted point-of-care (POC) biosensor for rapid, cost-effective, and accurate detection of PGF in whole serum of patients. The biosensor consists of dual FBG configurations on a tapered optical fiber. One FBG, sensitive to refractive index changes, is inscribed in the tapered region, while a second FBG inscribed in the non-tapered region responds to temperature only. The designed device enables PlGF detection by effectively mitigating temperature fluctuations. Microfluidic chip integration empowers analysis of tiny sample volumes (10 μL), enhancing its clinical applicability where sample availability may be limited. The developed biosensor achieves a detection limit of 5 pg/mL, with a dynamic range of 5–120 pg/mL on clinical serum samples, and demonstrates high specificity of 87.5%. Since PlGF levels in pre-eclamptic patients are usually less than 1 ng/mL, this performance remarkably empowers the use in clinical settings. The biosensor offers key advantages, including high sensitivity, low detection limits, minimal sample requirements, rapid analysis, and potentially low-cost production. These unique features make it a promising POC diagnostic tool for pre-eclampsia, promoting prompt detection and treatment, and ultimately enhancing patient care.