Reusable optofluidic point-of-care testing platform with lyophilized specific antibody for fluorescence detection of cholylglycine in serum

Abstract

A reusable optofluidic point-of-care testing platform (OPOCT) was successfully constructed through integrating evanescent wave fluorescence technology into an all-fiber-based optofluidic system. The compact design of the OPOCT allows it to be portable and suitable for on-site sensitive determination of biomarkers in serum without complicated and costly procedures. The sensitivity of 90.9 pM for antibody determination is observed thanks to the high transmission efficiency of excitation light and fluorescence in the OPOCT. The affinity constant between cholylglycine (CG) and anti-CG antibody was quantified using this platform based on the proposed theory. Using the lyophilized fluorescence-labeled specific antibody and reusable fiber optic biosensor, the OPOCT is applied to the one-step sensitive determination of CG in serum, which eliminates the dearth associated with liquid reagent handling, disposable biosensors, and user intervention. A limit of detection of 0.025 μg/mL for CG is obtained, which is far more than adequate for meeting diagnostic requirements. The matrix effect of serum samples on the evanescent wave-based optofluidic biosensor can be effectively reduced by simple dilution of serum samples. The performance of the OPOCT also compared favorably with that of a commercial turbidimetric inhibition immunoassay through analyzing multiple serum samples. This platform is ready to expand to measure any other biomarker by using its specific antibody. The simplicity, sensitivity, cost-effectiveness, and robustness of the OPOCT enable the early diagnosis of disease and making a timely clinical decision.

Immunosensor of Nitrofuran Antibiotics and Their Metabolites in Animal-Derived Foods: A Review

“…Fluorescent substances mainly include substances with fluorescence effect, such as fluorescein and its derivatives ( Hu et al, 2016 ), rhodamine ( Feng et al, 2002 ), quantum dots (QDs) ( Zhou et al, 2020 ), lanthanide chelates ( Lee et al, 2020 ), essence dyes ( Liu J. et al, 2020 ) and phycoerythrin ( Yang et al, 2020 ), as well as some substances that can emit fluorescence under the action of enzymes, which usually produce visible light after the irradiation of ultraviolet or X-ray. However, the sensitivity of the traditional fluorescein-labeled (fluorescein, etc.)…”

Clinical importance of laboratory biomarkers in liver fibrosis

“…One of the few studies on CG’s performance as a biomarker, Tanggo et al, revealed that CG concentration is elevated in patients with acute hepatitis and liver cirrhosis and could be used in screening individuals for cirrhosis ( 62 ). In a 2020 study, Liu et al ., showed that a reusable optofluidic point-of-care testing platform could be successfully adapted for the measurement of CG concentration in serum, with the authors noting that it can offer quick, easy and early diagnosis ( 63 ).…”

Application of Microfluidics in Immunoassay: Recent Advancements

“…ey integrated evanescent wave fluorescence technology into an all-fiber-based optofluidic system to increase the reusability of the system. Although the LOD was 0.025 μg/ mL which was not enough for diagnostic criteria, the sensitivity could be improved simply by the dilution of the serum sample [110]. Different from the previous attempt to enhance reusability, in 2020, Yang et al developed a low-cost disposable experimental device that could be mass-produced.…”