Evaluation of a Hydrogel-Based Diagnostic Approach for the Point-of-Care Based Detection of Neisseria gonorrhoeae.
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ABSTRACT:
SUBMITTER: Perera SR
PROVIDER: S-EPMC6164196 | biostudies-literature | 2018 Aug
REPOSITORIES: biostudies-literature
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Evaluation of a Hydrogel-Based Diagnostic Approach for the Point-of-Care Based Detection of <i>Neisseria gonorrhoeae</i>.
Perera Sumudu R SR Taheri Ali A Khan Nurul H NH Parti Rajinder P RP Stefura Stephanie S Skiba Pauline P Acker Jason P JP Martin Irene I Kusalik Anthony A Dillon Jo-Anne R JR
Antibiotics (Basel, Switzerland) 20180804 3
Eleven primer pairs were developed for the identification of <i>Neisseria gonorrhoeae</i>. The sensitivity and specificity of these primers were evaluated by Real Time (RT)-PCR melt curve analyses with DNA from 145 <i>N. gonorrhoeae</i> isolates and 40 other <i>Neisseria</i> or non-<i>Neisseria</i> species. Three primer pairs were further evaluated in a hydrogel-based RT-PCR detection platform, using DNA extracted from 50 <i>N. gonorrhoeae</i> cultures. We observed 100% sensitivity and specifici ...[more]
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Project description:Herein, we report results of the studies relating to the development of an impedimetric, magnetic bead-assisted supersandwich DNA hybridization assay for ultrasensitive detection of Neisseria gonorrhoeae, the causative agent of a sexually transmitted infection (STI), gonorrhea. First, a conductive ink was formulated by homogenously dispersing carboxylated multiwalled carbon nanotubes (cMWCNTs) in a stable emulsion of terpineol and an aqueous suspension of carboxymethyl cellulose (CMC). The ink, labeled C5, was coated onto paper substrates to fabricate C5@paper conductive electrodes. Thereafter, a magnetic bead (MB)-assisted supersandwich DNA hybridization assay was optimized against the porA pseudogene of N. gonorrhoeae. For this purpose, a pair of specific 5′ aminated capture probes (SCP) and supersandwich detector probes (SDP) was designed, which allowed the enrichment of target gonorrheal DNA sequence from a milieu of substances. The SD probe was designed such that instead of 1:1 binding, it allowed the binding of more than one T strand, leading to a ‘ladder-like’ DNA supersandwich structure. The MB-assisted supersandwich assay was integrated into the C5@paper electrodes for electrochemical analysis. The C5@paper electrodes were found to be highly conductive by a four-probe conductivity method (maximum conductivity of 10.1 S·cm−1). Further, the biosensing assay displayed a wide linear range of 100 aM-100 nM (109 orders of magnitude) with an excellent sensitivity of 22.6 kΩ·(log[concentration])−1. The clinical applicability of the biosensing assay was assessed by detecting genomic DNA extracted from N. gonorrhoeae in the presence of DNA from different non-gonorrheal bacterial species. In conclusion, this study demonstrates a highly sensitive, cost-effective, and label-free paper-based device for STI diagnostics. The ink formulation prepared for the study was found to be highly thixotropic, which indicates that the paper electrodes can be screen-printed in a reproducible and scalable manner.
| S-EPMC10136323 | biostudies-literature
Project description:BackgroundTimely detection and treatment are important for the control of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis. The objective of this study was to measure the performance of the Visby Medical Sexual Health Test, a single-use, point-of-care PCR device.MethodsWomen aged 14 years and older who presented consecutively to ten clinical sites across seven US states were enrolled for a cross-sectional, single-visit study. Patients who consented to participate, and who had not used any exclusionary products in the genital area in the previous 48 h, provided self-collected vaginal swabs for testing with the investigational device. Untrained operators received the specimens and ran the device using the guide provided. Specimens had to be run within 2 h of collection to be considered valid. For comparison, patient-infected status was derived by testing clinician-collected vaginal specimens with the Hologic Aptima Combo 2 Assay and Aptima Trichomonas vaginalis Assay, as well as the BD ProbeTec CT/GC Qx Amplified DNA Assay and BD ProbeTec Trichomonas vaginalis Qx Assay. If the results of those assays did not match, the BD MAX CT/GC/TV was used as a tiebreaker. The primary outcomes were the sensitivity and specificity of the investigational device for the detection of C trachomatis, N gonorrhoeae, and T vaginalis compared with patient-infected status.FindingsBetween Feb 25, 2019, and Jan 6, 2020, 1585 participants aged between 14 years and 80 years (mean 34·8 [SD 14·2]) were enrolled. 1555 participants had tests run with the investigational device, of whom 1532 (98·5%) had a valid result on either the first or repeat test. Among the patients with evaluable results (including a determinate patient-infected status), the device had a sensitivity of 97·6% (95% CI 93·2-99·2) and specificity of 98·3% (97·5-98·9) for C trachomatis (n=1457), sensitivity of 97·4% (86·5-99·5) and specificity of 99·4% (98·9-99·7) for N gonorrhoeae (n=1468), and sensitivity of 99·2% (95·5-99·9) and specificity of 96·9% (95·8-97·7) for T vaginalis (n=1449).InterpretationThis innovative, rapid, easy-to-use, single-use, point-of-care device to detect C trachomatis, N gonorrhoeae, and T vaginalis infections showed excellent sensitivity and specificity, and could represent an important advance in the development of rapid diagnostics for sexually transmitted infections and other infectious diseases.FundingDivision of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases.
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