Nanoparticle-Based Lateral Flow Biosensor Integrated With Loop-Mediated Isothermal Amplification for Rapid and Visual Identification of Chlamydia trachomatis for Point-of-Care Use

Abstract

Chlamydial infection, caused by Chlamydia trachomatis, is the most common bacterial sexually transmitted infection and remains a major public health problem worldwide, particularly in underdeveloped regions. Developing a rapid and sensitive point-of-care (POC) testing for accurate screening of C. trachomatis infection is critical for earlier treatment to prevent transmission. In this study, a novel diagnostic assay, loop-mediated isothermal amplification integrated with gold nanoparticle-based lateral flow biosensor (LAMP-LFB), was devised and applied for diagnosis of C. trachomatis in clinical samples. A set of LAMP primers based on the ompA gene from 14 C. trachomatis serological variants (serovar A-K, L1, L2, L3) was successfully designed and used for the development of C. trachomatis-LAMP-LFB assay. The optimal reaction system can be performed at a constant temperature of 67°C for 35 min. The total assay process, including genomic DNA extraction (~15 min), LAMP reaction (35 min), and LFB readout (~2 min), could be finished within 60 min. The C. trachomatis-LAMP-LFB could detect down to 50 copies/ml, and the specificity was 100%, no cross-reactions with other pathogens were observed. Hence, our C. trachomatis-LAMP-LFB was a rapid, reliable, sensitive, cost-effective, and easy-to-operate assay, which could offer an attractive POC testing tool for chlamydial infection screening, especially in resource starvation settings.

Visual and rapid identification of Chlamydia trachomatis and Neisseria gonorrhoeae using multiplex loop-mediated isothermal amplification and a gold nanoparticle-based lateral flow biosensor

“…The reaction's efficiency and specificity can be improved by incorporating two extra loop primers (LF and LB) into the LAMP reaction (McGinnis et al, 2021). We have previously used LAMP to detect C. trachomatis and N. gonorrhoeae, respectively, with an LoD as low as 50 copies per test (Chen et al, 2021;Chen et al, 2022). However, it was inadequate for simultaneously detecting these two important pathogens in a single test.…”

A rapid colorimetric lateral flow test strip for detection of live Salmonella Enteritidis using whole phage as a specific binder

“…However, the sensitivity of the phage-based lateral flow test strip in this study is lower than that of a previous report of an immuno-lateral flow assay for Salmonella Enteritidis and Typhimurium at 10 6 and 10 4 CFU/mL in culture media, respectively ( Moongkarndi et al, 2011 ). The sensitivity of the test strip can be further improved by exploring other reporting molecules such as luminescent nanoparticles ( Xie et al, 2014 ), carbon nanoparticles ( Noguera et al, 2011 ), and streptavidin-labeled AuNPs ( Chen et al, 2022 ).…”

Covalent Coupling Assisted Hydrophilic Perovskite Spheres for Ratiometric Fluorescent Visual Multichannel Immunoassay

“…[28] Therefore, we believe that this sensing platform is expected to be used for early diagnosis of hepatitis B. By investigating the relevant literature, the ratiometric fluorescence immunoassay based on hydrophilic perovskite fluorescent microspheres used in this study was compared with the results obtained by other researchers through different methods, [29][30][31][32][33][34] as shown in Table 2. It can be seen that the immunoassay proposed in this study had a wide linear range and low detection limit, indicating the successful exploration of perovskite materials as biosensors.…”