Cuillière ML, Abbadi M, Molé C, Montagne P, Béné MC, Faure G. Microparticle-enhanced nephelometric immunoassay of alpha-lactalbumin in human milk.
JOURNAL OF IMMUNOASSAY 1997;
18:97-109. [PMID:
9139050 DOI:
10.1080/01971529708005806]
[Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A microparticle-enhanced nephelometric immunoassay was developed for alpha-lactalbumin quantitation in human milk. It is based on the nephelometric measurement of the light scattered during the competitive immunoagglutination of a microparticle-alpha-lactalbumin conjugate with an anti-alpha-lactalbumin antiserum. This immunoassay is sensitive (detection limit in reaction mixture, 1.5 micrograms/L) and could be performed in high dilution of milk, excluding any interference or sample pretreatment. It allowed the quantification of alpha-lactalbumin on a large range of concentrations (0.5-16.9 g/L) with accuracy (linear recovery in dilution-overloading assay) and precision (within- and between-run coefficients of variation from 1 to 7%). Changes in the alpha-lactalbumin concentration of human milk during lactation were determined in 162 samples. The concentration and ratio of alpha-lactalbumin total protein were found to be significantly lower in colostrum (4.9 g/l, 27%) than in transitional milk (5.2 g/L, 40%), then decreased in mature milk (3.4 g/L, 31%).
Collapse