Protein: Baby Formulas vs. Human Breast Milk Katherine E. Oliver

Polaris K-12 BioTaPP Program, Under the Direction of Aaron Kallas

– How do the proteins in baby formulas compare to those in human breast milk? – The proteins in baby formulas are derived from non-human sources. Human Breast milk is specifically formulated to meet the needs of human babies. – My mission: To determine how similar the proteins in assorted baby formulas are to those in human breast milk.

Bradford 1)  Mix up formulas according to label instructions (making very certain to get volumes and concentrations exact) 2)  Dilute samples (helps the experiments run more smoothly – I found a 1:10 dilution factor to be most effective) 3)  Use the Bradford Reagent in combination with the UV Spectrophotometer to quantify protein concentrations in samples

SDS-Page 1)   Take dilute

samples (1:10) and extract proteins using the Laemmli sample buffer

2)   Load and run in a polyacrylamide gel using a vertical electrophoresis rig

3)   Stain gel 4)   Analyze banding

pattern 5)   Create standard

curve. 6)   Use the

standard curve to determine the mass (kDa) of proteins found in the samples through the banding pattern.

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Bibliography