Development of diagnostic platforms using gold nanoparticles for early detection of Xanthomonas arborícola juglandis responsable of apical necrosis in walnuts

NATALIA GARRO; FRANCISCO ORTEGA SÁNCHEZ; MARTÍN RINALDI TOSI; MARTÍN A. FERNÁNDEZ BALDO

Sao Paulo

Congreso; Biotechnology World Convention; 2016

OMICS International

Development of diagnostic platforms using gold nanoparticles for early detection of Xanthomonas arborícola juglandis responsable of apical necrosis in walnuts.Martin RINALDI-TOSI1, Natalia GARRO1, Francisco ORTEGA-SANCHEZ2, Martin FERNANDEZ-BALDO31- Laboratory of Food Technology and Biotechnology (LaTBiA-CONICET). Rio Negro National University (UNRN), Argentina.2- Laboratory of Biodynamics. GENYO Institute. PFIZER-University of GRANADA, Spain.3- Laboratory of Bioanalític and Nanotechnology. Chemistry Institute of San Luis (INQUISAL-CONCIET). San Luis National University (UNSL), Chacabuco 917. D5700BWS. San Luis, ArgentinaXanthomonas arborícola juglandis is the main causative microorganism of brown apical necrosis in walnuts (Juglans regia L.), in addition to secondary fungal pathogens such as Fusarium and Alternaria species. This pathology is responsible of premature drop fruit and economic losses of over 70%, were detected in 2012 in Rio Negro valley. This study aims to develop methods that allow early diagnosis anticipate infection by microorganisms and act quickly. For this, gold nanoparticles were synthesized by chemical reduction using tetrachloroauric acid and sodium citrate, and functionalized with chitosan. Nanoparticles (NPs Au-CH) were subsequently characterized by several techniques. The results of UV-visible spectroscopy tests showed a characteristic band at 530 nm; studies of scanning electron microscopy (SEM) showed homogeneous and spherical morphology and particules size of 15±5 nm; energy dispersive spectrometry (EDS) assay showed a characteristic spectrum of 2 keV and X-ray fluorescence (XRF) with characteristic peaks between 37° and 38°. Finally, Xanthomonas arboricola antibodies were immobilized on the NPs Au-CH surface using glutaraldehyde, obtaining as result a nanostructured platform for the development of an immunosensor for early detection of this microorganism. We concluded that the nanostructured platform can be used to attach different specific biomolecules that recognize microorganisms responsible of apical necrosis and thus make early detection before that occur physic manifestation of the symptomatology.BiographyDr. Martín Fernández Baldo received his PhD in analytical chemistry in 2011 at Universidad Nacional de San Luis, Argentina and postdoctotal position in: Universidade Estadual de Campinas, Brasil and GENYO, Universidad de Granada, España. He is currently a teacher assistance of clinical analysis area at the Universidad Nacional de San Luis. Dr. Fernández-Baldo?s research interest comprises the synthesis and characterization of nanomaterials for its incorporation as platforms for immobilization of biomolecules in biosensors for clinical applications.Presenting author details Full name: Martin Edgardo RINALDI TOSIContact number: 542616117418Twitter account:Linked In account: Martin RINALDI-TOSISession name/number:Category: Poster presentation