Determination of protein in milk powder using 2-sulfophenylazo-rhodanine as a probe by the enhanced resonance Rayleigh light-scattering technique.
In this paper, the interaction between 2-sulfophenylazo-rhodanine and protein was investigated by Rayleigh light-scattering technique. Based on this, a novel method for the determination of protein was developed. The effects of different conditions, such as acidity and media, were investigated thoroughly, and the optimum conditions were confirmed. Bis(2-ethylhexyl)sulfosuccinate (AOT) microemulsion, which is introduced into the protein determination, markedly increased the sensitivity of the system by changing the microenvironment. In pH 2.80 Britton-Robinson buffer solution in the presence of AOT microemulsion, the detection limits of bovine serum albumin, human serum albumin, ovalbumin, and gamma-globulin are 5.4, 4.5, 9.8, and 10.1 ng/mL, respectively. The method developed in this paper has been applied to the determination of protein in milk powder with satisfactory results.
Wei
Qin
Q
Jinan University, School of Chemistry and Chemical Engineering, Jinan, People's Republic of China. sdjndxwq@263.net
Li
Yan
Y
Dong
Wenying
W
Du
Bin
B
D000818:Animals; D002417:Cattle; D005504:Food Analysis / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008027:Light; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000032:analysis* / Q000592:standards; D015336:Molecular Probe Techniques; D010047:Ovalbumin / Q000032:analysis; D011208:Powders; D012236:Rhodanine / Q000031:analogs & derivatives; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012709:Serum Albumin / Q000032:analysis; D012710:Serum Albumin, Bovine / Q000032:analysis; D013386:Succinates; D005719:gamma-Globulins / Q000032:analysis
C512554:1,4-bis(2-ethylhexyl) sodium sulfosuccinate; D008894:Milk Proteins; D011208:Powders; D012709:Serum Albumin; D013386:Succinates; D005719:gamma-Globulins; D012710:Serum Albumin, Bovine; D012236:Rhodanine; D010047:Ovalbumin