Sodium dodecyl sulfate-capillary gel electrophoresis of polyethylene glycolylated interferon alpha

2004 ◽  
Vol 25 (3) ◽  
pp. 476-479 ◽  
Author(s):  
Dong H. Na ◽  
Eun J. Park ◽  
Yu S. Youn ◽  
Byung W. Moon ◽  
Yeong W. Jo ◽  
...  
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Interferon Alpha ◽  
Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Capillary Gel Electrophoresis ◽  
Dodecyl Sulfate

Quantification of Whey Protein Content in Infant Formulas by Sodium Dodecyl Sulfate-Capillary Gel Electrophoresis (SDS-CGE): Single-Laboratory Validation, First Action 2016.15

2017 ◽  
Vol 100 (2) ◽  
pp. 510-521 ◽  
Author(s):  
Ping Feng ◽  
Christophe Fuerer ◽  
Adrienne McMahon
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Protein Content ◽  
Whey Protein ◽  
Gel Electrophoresis ◽  
Whey Proteins ◽  
Sodium Dodecyl ◽  
Infant Formulas ◽  
Method Performance ◽  
Capillary Gel Electrophoresis ◽  
Dodecyl Sulfate

Abstract Protein separation by sodium dodecyl sulfate-capillary gel electrophoresis, followed by UV absorption at 220 nm, allows for the quantification of major proteins in raw milk. In processed dairy samples such as skim milk powder (SMP) and infant formulas, signals from individual proteins are less resolved, but caseins still migrate as one family between two groups of whey proteins. In the first group, α-lactalbumin and β-lactoglobulin migrate as two distinct peaks. Lactosylated adducts show delayed migration times and interfere with peak separation, but both native and modified forms as well as other low-MW whey proteins still elute before the caseins. The second group contains high-MW whey proteins (including bovine serum albumin, lactoferrin, and immunoglobulins) and elutes after the caseins. Caseins and whey proteins can thus be considered two distinct nonoverlapping families whose ratio can be established based on integrated areas without the need for a calibration curve. Because mass-to-area response factors for whey proteins and caseins are different, an area correction factor was determined from experimental measurement using SMP. Method performance assessed on five infant formulas showed RSDs of 0.2–1.2% (within day) and 0.5–1.1% (multiple days), with average recoveries between 97.4 and 106.4% of added whey protein. Forty-three different infant formulas and milk powders were analyzed. Of the 41 samples with manufacturer claims, the measured whey protein content was in close agreement with declared values, falling within 5% of the declared value in 76% of samples and within 10% in 95% of samples.

Characterization of the H- and L-Subunit Ratios of Ferritins by Sodium Dodecyl Sulfate–Capillary Gel Electrophoresis

2002 ◽  
Vol 302 (2) ◽  
pp. 263-268 ◽  
Author(s):  
John K. Grady ◽  
Jia Zang ◽  
Thomas M. Laue ◽  
Paolo Arosio ◽  
N.Dennis Chasteen
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Capillary Gel Electrophoresis ◽  
Dodecyl Sulfate

scholarly journals Determination of Vegetal Proteins in Milk Powder by Sodium Dodecyl Sulfate–Capillary Gel Electrophoresis: Interlaboratory Study

2002 ◽  
Vol 85 (5) ◽  
pp. 1090-1095 ◽  
Author(s):  
María A Manso ◽  
Tiziana Maria Cattaneo ◽  
Stefania Barzaghi ◽  
Cornelis Olieman ◽  
Rosina López-Fandiño ◽  
...  
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Total Protein ◽  
Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Milk Powder ◽  
Interlaboratory Study ◽  
Capillary Gel Electrophoresis ◽  
Dodecyl Sulfate ◽  
Pea Proteins

Abstract An interlaboratory study, with the participation of 8 laboratories, was conducted to evaluate a sodium dodecyl sulfate–capillary gel electrophoresis method for determination of adulteration of milk powder with soy and pea proteins. Calibration standards (0–8%, w/w, soy and pea protein in total protein) and adulterated skim milk powders (0–5%, w/w, soy and pea proteins in total protein) were produced. Vegetal proteins were determined after removal of milk proteins by pretreatment of the samples with tetraborate–EDTA buffer, pH 8.3. Repeatability standard deviations ranged from 9 to 15% and reproducibility standard deviations ranged from 25 to 30% in the samples containing 5% vegetal protein in total protein.

Sign in / Sign up

Export Citation Format

Share Document