A Low-Cost, High-Performance System for Fluorescence Lateral Flow Assays

Biosensors

Linda G. Lee¹  Eric S. Nordman¹  Martin D. Johnson² 

[1]Song Diagnostic Research LLC, 1 Megans Lane, Woodside, CA 94062, USA

关键词: fluorescence lateral flow immunoassay;    phycoerythrin;    biotinylated BSA;    hCG;   

DOI  :  10.3390/bios3040360

来源: mdpi

【 摘 要 】

We demonstrate a fluorescence lateral flow system that has excellent sensitivity and wide dynamic range. The illumination system utilizes an LED, plastic lenses and plastic and colored glass filters for the excitation and emission light. Images are collected on an iPhone 4. Several fluorescent dyes with long Stokes shifts were evaluated for their signal and nonspecific binding in lateral flow. A wide range of values for the ratio of signal to nonspecific binding was found, from 50 for R-phycoerythrin (R-PE) to 0.15 for Brilliant Violet 605. The long Stokes shift of R-PE allowed the use of inexpensive plastic filters rather than costly interference filters to block the LED light. Fluorescence detection with R-PE and absorbance detection with colloidal gold were directly compared in lateral flow using biotinylated bovine serum albumen (BSA) as the analyte. Fluorescence provided linear data over a range of 0.4–4,000 ng/mL with a 1,000-fold signal change while colloidal gold provided non-linear data over a range of 16–4,000 ng/mL with a 10-fold signal change. A comparison using human chorionic gonadotropin (hCG) as the analyte showed a similar advantage in the fluorescent system. We believe our inexpensive yet high-performance platform will be useful for providing quantitative and sensitive detection in a point-of-care setting.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.