{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T22:10:11Z","timestamp":1788473411526,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2024,10,18]],"date-time":"2024-10-18T00:00:00Z","timestamp":1729209600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Srinakharinwirot University","award":["059\/2565"],"award-info":[{"award-number":["059\/2565"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background: Venereal syphilis in humans is caused by Trepenoma pallidum subspp. pallidum. A study has shown that 30,302 individuals in Thailand had syphilis in 2020, with a male-to-female ratio of 1:0.8 and the highest incidence rate at ages between fifteen and twenty-four. Methods: This research aimed to develop a loop-mediated isothermal amplification assay using gold nanoparticles (LAMP-AuNPs). Analytical sensitivity, diagnostic specificity, accuracy, and predictive values for each technique are provided. Results: The diagnosis sensitivities of polymerase chain reaction using agarose gel electrophoresis (PCR-AGE), loop-mediated isothermal amplification assay using agarose gel electrophoresis (LAMP-AGE), and LAMP-AuNPs were 116 ng\/\u00b5L, 11.6 ng\/\u00b5L, and 11.6 ng\/\u00b5L, respectively. We evaluated the analytical specificity using PCR and a LAMP-based assay, and there was no cross-reactivity to Leptospira interrogans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, human immunodeficiency virus (HIV), and healthy humans. After analyzing 400 serum samples of patients suspected of syphilis, the LAMP-AGE and LAMP-AuNPs assays displayed 100% diagnostic sensitivity scores, 91% diagnostic specificity scores, 95.5% accuracy rates, 100% positive predictive values (PPVs), and 91% negative predictive values (NPVs), the positive likelihood ratio (LR+) was 11.11, while the negative likelihood ratio (LR\u2212) was 0. Conversely, for PCR assays displayed 100% diagnostic sensitivity scores, 94.5% diagnostic specificity scores, 97.25% accuracy rates, 100% PPVs, and 94.5% NPVs, LR+ was 18.18, and LR\u2212 was 0. Conclusions: The LAMP-AuNPs technique demonstrates rapidity, affordability, and convenience, rendering it well-suited for point-of-care applications in the diagnosis, prevention, and management of pathogenic infections.<\/jats:p>","DOI":"10.3390\/diagnostics14202323","type":"journal-article","created":{"date-parts":[[2024,10,18]],"date-time":"2024-10-18T06:46:52Z","timestamp":1729234012000},"page":"2323","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Loop-Mediated Isothermal Amplification Assay Using Gold Nanoparticles for Detecting Treponema pallidum subspp. pallidum"],"prefix":"10.3390","volume":"14","author":[{"given":"Saranthum","family":"Phurijaruyangkun","sequence":"first","affiliation":[{"name":"Faculty of Medicine, Srinakharinwirot University, Bangkok 10110, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pongbun","family":"Tangjitrungrot","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biosensors, Panyananthaphikhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi 11120, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pornpun","family":"Jaratsing","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biosensors, Panyananthaphikhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi 11120, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suphitcha","family":"Augkarawaritsawong","sequence":"additional","affiliation":[{"name":"Faculty of Medical Technology, Rangsit University, Pathum Thani 12000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6238-1070","authenticated-orcid":false,"given":"Sawanya","family":"Pongparit","sequence":"additional","affiliation":[{"name":"Faculty of Medical Technology, Rangsit University, Pathum Thani 12000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rungnapa","family":"Veeramano","sequence":"additional","affiliation":[{"name":"Faculty of Medical Technology, Rangsit University, Pathum Thani 12000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kularb","family":"Tanomnuch","sequence":"additional","affiliation":[{"name":"Clinical and Anatomical Pathology, Panyananthaphikhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi 11120, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2838-1875","authenticated-orcid":false,"given":"Supatra","family":"Areekit","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biosensors, Panyananthaphikhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi 11120, Thailand"},{"name":"Innovative of Learning, Srinakharinwirot University, Bangkok 10110, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosum","family":"Chansiri","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biosensors, Panyananthaphikhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi 11120, Thailand"},{"name":"Srinakharinwirot University, Bangkok 10110, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Somchai","family":"Santiwatanakul","sequence":"additional","affiliation":[{"name":"Center of Excellence in Biosensors, Panyananthaphikhu Chonprathan Medical Center, Srinakharinwirot University, Nonthaburi 11120, Thailand"},{"name":"Srinakharinwirot University, Bangkok 10110, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,18]]},"reference":[{"key":"ref_1","first-page":"54","article-title":"Epidemiological characteristics among patients with syphilis in Thailand","volume":"49","author":"Chaisongkram","year":"2023","journal-title":"Dis. 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