Publications by authors named "N Sivaprasad"

We share our experience in the development of immunoradiometric assay (IRMA) for gonadotropins, FSH and LH using common tracer concept. Commercially procured, monoclonal antibody against 'common epitope' of FSH and LH was radiolabeled and epitope specific monoclonal antibody against β-subunit of FSH and LH was chemically immobilized and used as a capture system. In an inclusive assay procedure developed, 100 µl of respective standard and specific capture antibody was incubated with 100 µl common tracer, for 3 h at RT with shaking.

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Background & Objectives: Estimation of parathyroid hormone (PTH) levels is important in the management of metabolic bone disorders. Here we describe a simple, sensitive and specific second generation immunoradiometric assay (IRMA) to detect intact PTH levels using different solid phase matrices. Different methods for immobilization of antibodies have also been evaluated.

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Luciferase from Indian firefly Luciola praeusta (Coleoptera: Lampyridae: Luciolinae) was isolated and the properties compared with that of the North American firefly, Photinus pyralis. Luciola praeusta luciferase was purified using acetone extraction, gel-filtration column chromatography, ammonium sulfate precipitation and anion exchange chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates a homogeneous preparation and the molecular mass was slightly higher than that of Photinus pyralis.

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Different monoclonal antibodies, both commercial and indigenously produced, were evaluated in various combinations to optimize an immunoradiometric assay (IRMA) system for human thyroid stimulating hormone (hTSH). During these studies, it was observed that mixing one of the indigenously produced hTSH monoclonal antibody (2B11) in the hTSH IRMA system using Immunotech (Beckman Coulter, Czech Republic) kit reagents, led to an overall increase in the assay binding and sensitivity (from 0.025 mIU/L to 0.

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A sensitive immunoenzymometric assay (IEMA) of serum thyrotropin (hTSH) was developed using anti-hTSH rabbit polyclonal antibody and anti-hTSH in-house monoclonal antibody with a sensitivity of 0.12 mIU/L. Serum samples were incubated in ELISA wells precoated with polyclonal antibody.

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