title: Design and development of a field applicable gold nanosensor for the detection of luteinizing hormone.
abstract: In this paper, we describe a novel strategy for the fabrication of a nanosensor for detecting luteinizing hormone (LH) of sheep using a gold nanoparticle-peptide conjugate. A new peptide sequence "CDHPPLPDILFL" (leutinizing hormone peptide, LHP) has been identified, using BLAST and Clustal W analysis, to detect antibody of LH (sheep). LHP has been synthesized and characterized, and their affinity toward anti-LH was established using enzyme linked immunosorbant assay (ELISA) technique. The thiol group in LHP directly binds with gold nanoparticles (AuNPs) to yield AuNP-LHP construct. Detailed physicochemical analysis of AuNP-LHP construct was determined using various analytical techniques. Nanosensor using gold nanoparticle peptide conjugate was developed on the basis of competitive binding of AuNP-LHP and LH toward anti-LH. Nitrocellulose membrane, precoated with anti-LH, was soaked in the mixture of AuNP-LHP and sample of analysis (LH). In the absence of LH (sheep), anti-LH coated on the membrane binds with AuNP-LHP, leading to a distinctive red color, while in the presence of LH, no color appeared in the membrane due to the interaction of anti-LH with LH thereby preventing the binding of AuNP-LHP with membrane bound anti-LH. The sensor assay developed in this study can detect LH (sheep) up to a minimal concentration of ∼50 ppm with a high degree of reproducibility and selectivity. The gold-nanoparticle-peptide based nanosensor would be a simple, portable, effective, and low cost technique for infield applications.
authors.affiliation: Department of Radiology, University of Missouri, Columbia, Missouri 65212, United States.
authors.forename: Ajit
authors.initials: A
authors.lastname: Zambre
authors.forename: Nripen
authors.initials: N
authors.lastname: Chanda
authors.forename: Sudhirdas
authors.initials: S
authors.lastname: Prayaga
authors.forename: Rosana
authors.initials: R
authors.lastname: Almudhafar
authors.forename: Zahra
authors.initials: Z
authors.lastname: Afrasiabi
authors.forename: Anandhi
authors.initials: A
authors.lastname: Upendran
authors.forename: Raghuraman
authors.initials: R
authors.lastname: Kannan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation*; D004797:Enzyme-Linked Immunosorbent Assay; D004867:Equipment Design; D006046:Gold / Q000737:chemistry*; D007986:Luteinizing Hormone / Q000032:analysis* / Q000097:blood / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D009842:Oligopeptides / Q000737:chemistry; D013499:Surface Properties
chemical_list: D009842:Oligopeptides; D006046:Gold; D007986:Luteinizing Hormone