{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T13:03:14Z","timestamp":1785157394033,"version":"3.55.0"},"reference-count":26,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T00:00:00Z","timestamp":1785110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006245","name":"Viet Nam Ministry of Science and Technology","doi-asserted-by":"publisher","award":["03.M04.2024"],"award-info":[{"award-number":["03.M04.2024"]}],"id":[{"id":"10.13039\/501100006245","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Methods Protoc.","MPs"],"abstract":"<jats:p>Viral diseases are one of the most destructive threats to global agriculture. Among plant viruses, tobacco mosaic virus (TMV) is a highly contagious pathogen infecting numerous economically vital crops. With no curable treatments, the only strategy to mitigate virus spread is early detection and plant removal. The gold standard for TMV detection is reverse transcriptase-polymerase chain reaction (RT-PCR), followed by agarose gel electrophoresis. To reduce TMV diagnosis time and eliminate the requirement for expensive equipment, this study developed and optimized a one-step RT-PCR-coupled cysteamine-functionalized gold nanoparticle assay for the colorimetric determination of the virus. By integrating cDNA synthesis and PCR amplification into a single tube and analyzing the results using cysteamine- functionalized gold nanoparticles (Au@Cys), the diagnosis turnaround time was significantly reduced. Furthermore, this AuNPs-based colorimetric assay enabled straightforward visual inspection with the naked eye, eliminating the need for costly optical devices. Additionally, our regression equation linking RT-PCR product color values, extracted as mean A value based on the CIELAB color space (green-red axis), and viral load allows for the accurate quantification of TMV infection levels in field samples. Our research lays the groundwork for the further development of more cost-effective, quantitative and rapid plant virus diagnosis methods.<\/jats:p>","DOI":"10.3390\/mps9040111","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T11:54:26Z","timestamp":1785153266000},"page":"111","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A One-Step RT-PCR-Coupled Cysteamine-Functionalized Gold Nanoparticle Assay for Colorimetric Detection of Tobacco Mosaic Virus"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-9835-0952","authenticated-orcid":false,"given":"Thuy-Duong Thi","family":"Tran","sequence":"first","affiliation":[{"name":"Vietnam-Korea Institute of Science and Technology, Hoa Lac High-Teck Park, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quy Thi","family":"Vu","sequence":"additional","affiliation":[{"name":"Vietnam-Korea Institute of Science and Technology, Hoa Lac High-Teck Park, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hoa Thi","family":"Hoang","sequence":"additional","affiliation":[{"name":"Vietnam-Korea Institute of Science and Technology, Hoa Lac High-Teck Park, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-0744-0930","authenticated-orcid":false,"given":"Phan Thi Ngoc","family":"Hoa","sequence":"additional","affiliation":[{"name":"Vietnam-Korea Institute of Science and Technology, Hoa Lac High-Teck Park, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nguyen Pham Thi","family":"Thao","sequence":"additional","affiliation":[{"name":"Center for Materials Innovation and Technology, VinUniversity, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2440-2576","authenticated-orcid":false,"given":"Truong T. N.","family":"Lien","sequence":"additional","affiliation":[{"name":"Vietnam-Korea Institute of Science and Technology, Hoa Lac High-Teck Park, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1094\/PHYTO-05-22-0167-RVW","article-title":"Plant viruses of agricultural importance: Current and future perspectives of virus disease management strategies","volume":"113","author":"Tatineni","year":"2023","journal-title":"Phytopathology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1105\/tpc.11.3.301","article-title":"Tobacco mosaic virus: Pioneering research for a century","volume":"11","author":"Creager","year":"1999","journal-title":"Plant Cell"},{"key":"ref_3","first-page":"27","article-title":"Tobacco mosaic virus","volume":"11","author":"Carr","year":"2004","journal-title":"Annu. Plant Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"136909","DOI":"10.1016\/j.snb.2024.136909","article-title":"Rapid visual detection of tobacco mosaic virus using a portable paper-based molecularly imprinted sensor","volume":"424","author":"Gong","year":"2025","journal-title":"Sens. Actuators B Chem."},{"key":"ref_5","first-page":"723","article-title":"Effects of Planting Season Shifts on Major insect Pests and virus diseases of Tobacco in Northern Vietnam: A Review","volume":"26","author":"Giang","year":"2026","journal-title":"Ronika J."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1146\/annurev.phyto.42.040803.140322","article-title":"Tobacco mosaic virus: A model system for plant biology","volume":"42","author":"Scholthof","year":"2004","journal-title":"Annu. Rev. Phytopathol."},{"key":"ref_7","first-page":"521","article-title":"Milestones in research on tobacco mosaic virus","volume":"354","author":"Harrison","year":"1999","journal-title":"Philos. Trans. R. Soc. Lond. Ser. B Biol. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"427","DOI":"10.15835\/nbha4129008","article-title":"The effects of tobacco mosaic virus infection on growth and physiological parameters in some pepper varieties (Capsicum annuum L.)","volume":"41","author":"Pazarlar","year":"2013","journal-title":"Not. Bot. Horti Agrobot. Cluj-Napoca"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/S0065-3527(08)60423-6","article-title":"Tobacco mosaic virus: Model for structure and function of a simple virus","volume":"Volume 26","author":"Hirth","year":"1981","journal-title":"Advances in Virus Research"},{"key":"ref_10","first-page":"569","article-title":"Historical overview of research on the tobacco mosaic virus genome: Genome organization, infectivity and gene manipulation","volume":"354","author":"Okada","year":"1999","journal-title":"Philos. Trans. R. Soc. Lond. Ser. B Biol. Sci."},{"key":"ref_11","first-page":"613","article-title":"Replication of tobacco mosaic virus RNA","volume":"354","author":"Buck","year":"1999","journal-title":"Philos. Trans. R. Soc. Lond. Ser. B Biol. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1007\/s00018-002-8406-x","article-title":"The spread of tobacco mosaic virus infection: Insights into the cellular mechanism of RNA transport","volume":"59","author":"Heinlein","year":"2002","journal-title":"Cell. Mol. Life Sci."},{"key":"ref_13","first-page":"603","article-title":"Tobacco mosaic virus and the study of early events in virus infections","volume":"354","author":"Shaw","year":"1999","journal-title":"Philos. Trans. R. Soc. Lond. Ser. B Biol. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1111\/j.1472-765X.2011.03117.x","article-title":"Detection of Tobacco mosaic virus and Tomato mosaic virus in pepper and tomato by multiplex RT\u2013PCR","volume":"53","author":"Kumar","year":"2011","journal-title":"Lett. Appl. Microbiol."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Chang, C.-C., Chen, C.-P., Wu, T.-H., Yang, C.-H., Lin, C.-W., and Chen, C.-Y. (2019). Gold nanoparticle-based colorimetric strategies for chemical and biological sensing applications. Nanomaterials, 9.","DOI":"10.3390\/nano9060861"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"49211","DOI":"10.1021\/acsomega.3c07503","article-title":"Staining-enhanced peroxidase-mimicking gold nanoparticles in nano-ELISA for highly sensitive detection of Klebsiella Pneumoniae","volume":"8","author":"Pham","year":"2023","journal-title":"ACS Omega"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.jviromet.2018.12.011","article-title":"A multiplex reverse transcription PCR assay for simultaneous detection of six main RNA viruses in tomato plants","volume":"265","author":"Liu","year":"2019","journal-title":"J. Virol. Methods"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2739","DOI":"10.1021\/cr2001178","article-title":"Gold nanoparticles in chemical and biological sensing","volume":"112","author":"Saha","year":"2012","journal-title":"Chem. Rev."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1631","DOI":"10.1111\/1750-3841.14179","article-title":"Cysteamine-Modified Gold Nanoparticles as a Colorimetric Sensor for the Rapid Detection of Gentamicin","volume":"83","author":"Gukowsky","year":"2018","journal-title":"J. Food Sci."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2633","DOI":"10.1039\/C7AY00368D","article-title":"Methods for preparing DNA-functionalized gold nanoparticles, a key reagent of bioanalytical chemistry","volume":"9","author":"Liu","year":"2017","journal-title":"Anal. Methods"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"6666","DOI":"10.1021\/la0202428","article-title":"Sequence-dependent stability of DNA-modified gold nanoparticles","volume":"18","author":"Storhoff","year":"2002","journal-title":"Langmuir"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"819","DOI":"10.1016\/j.talanta.2016.09.032","article-title":"Colorimetric detection of Cr (VI) based on the leaching of gold nanoparticles using a paper-based sensor","volume":"161","author":"Guo","year":"2016","journal-title":"Talanta"},{"key":"ref_23","unstructured":"Guzaev, M., Li, X., Park, C., Leung, W.-Y., and Roberts, L. (2026, July 06). Comparison of Nucleic Acid Gel Stains Cell Permeability, Safety, and Sensitivity of Ethidium Bromide Alternatives. Available online: https:\/\/biotium.com\/wp-content\/uploads\/2017\/02\/Gel-Stains-Comparison.pdf."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1186\/s12985-016-0639-7","article-title":"Ecogenomic survey of plant viruses infecting tobacco by next generation sequencing","volume":"13","author":"Akinyemi","year":"2016","journal-title":"Virol. J."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"260","DOI":"10.5423\/PPJ.OA.09.2012.0145","article-title":"Prevalence of tobacco mosaic virus in Iran and evolutionary analyses of the coat protein gene","volume":"29","author":"Alishiri","year":"2013","journal-title":"Plant Pathol. J."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Yatish, K., Ambika, D., Venkataravanappa, V., Shankarappa, K., Manjunatha, L., Uppala, L., and Tejashwini, N. (2025). Tobacco Mosaic Virus. Compendium of Phytopathogenic Microbes in Agro-Ecology: Vol. 2 Viruses and Viroids, Springer.","DOI":"10.1007\/978-3-031-81884-4_20"}],"container-title":["Methods and Protocols"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2409-9279\/9\/4\/111\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T12:26:16Z","timestamp":1785155176000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2409-9279\/9\/4\/111"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,27]]},"references-count":26,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["mps9040111"],"URL":"https:\/\/doi.org\/10.3390\/mps9040111","relation":{},"ISSN":["2409-9279"],"issn-type":[{"value":"2409-9279","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,27]]}}}