Show simple item record

dc.contributor.authorAoko, Ivy Lynn
dc.contributor.authorOndigo, Dezzline
dc.contributor.authorKavoo, Agnes Mumo
dc.contributor.authorWainaina, Cornelius
dc.contributor.authorKiirika, Leonard
dc.date.accessioned2021-04-16T07:50:53Z
dc.date.available2021-04-16T07:50:53Z
dc.date.issued2021-01-27
dc.identifier.issn2322-1461
dc.identifier.issn2588-3143
dc.identifier.urihttps://karuspace.karu.ac.ke/handle/20.500.12092/2499
dc.description.abstractWe report a simple colorimetric probe based on gold nanoparticles (AuNPs) for detecting Ralstonia solanacearum. The AuNPs were synthesized through reduction with citrate ion and characterized by ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The freshly synthesized AuNPs were brick red due to an intense surface plasmon absorption band at 520 nm. Upon interaction with synthetic gibberellic acid (GA3), a bathochromic shift occurred in the surface plasmon resonance (SPR) peak of AuNPs to higher wavelengths. The 'eye-ball' limit of detection was 0.2 ppm. This shift was accompanied by a change in the color of the AuNPs from brick red to purple. Soil samples were collected from the rhizosphere of tomato plants, exhibiting bacterial wilt symptoms and pure cultures of Ralstonia solanacearum isolated using a modified Kelman’s TZC medium. Gibberellins (GA) were extracted from the culture of R. solanacearum using ethyl acetate and characterized using fourier transform infrared spectroscopy (FT-IR). AuNP solution aggregation was induced by GA-mediated R. solanacearum. A color change from brick red to purple was also observed. The results illustrated the use of both SPR wavelength-shift sensing and visual color change to detect molecules of biological relevanceen_US
dc.language.isoenen_US
dc.publisherInternational Journal of Horticultural Science and Technologyen_US
dc.subjectBacterial wilten_US
dc.subjectBiosensoren_US
dc.subjectAuNPsen_US
dc.subjectTomatoen_US
dc.titleA Gold Nanoparticle-Based Colorimetric Probe for Detection of Gibberellic Acid Exuded by Ralstonia solanacearum Pathogen in Tomato (Solanum lycopersicum L.)en_US
dc.typeArticleen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record