RESUMO
Automated, rapid, sensitive, and label-free biosensor-based immunoassays for immunoglobulin G (IgG), folate binding protein, lactoferrin, and lactoperoxidase in bovine milk using surface plasmon resonance optical detection with direct binding assay format are described. Samples are prepared for analysis by direct dilution into buffer. Analysis conditions, including ligand immobilization, flow rate, contact time, and regeneration are defined and nonspecific binding considerations evaluated. The technique has been applied to the measurement of these proteins in consumer milks, colostrum, milk products, and infant formulas, and their temporal change during early bovine lactation followed.
Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Colostro/metabolismo , Proteínas do Leite/análise , Animais , Calibragem , Proteínas de Transporte/análise , Bovinos , Receptores de Folato com Âncoras de GPI , Imunoglobulina G/análise , Lactoferrina/análise , Lactoperoxidase/análise , Ligantes , Proteínas do Leite/química , Receptores de Superfície Celular/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de TempoRESUMO
The immunoprotective properties of bovine milk immunoglobulin G (IgG) have led to a recent proliferation of nutritional products incorporating this protein. It has therefore become critical that reliable analytical techniques for the measurement of the IgG content in such products are available. This literature review surveys current methods of analysis for IgG, including separation-based or immuno-based concentration analysis. The review also discusses nutraceutical applications, regulatory issues, stability of IgG and the significance of primary reference material in IgG analysis.