Buffers Mcllvaine

It should also be kept in mind that the pigment solution under investigation should exhibit a constant pH. Mcllvaine buffer was found to be the most suitable because it contains both citric acid and phosphate ions previously reported to enhance betalain stability. According to our observations, a pH of 6.0 or 6.5 should be chosen for spectrophotometric quantification, and not more than 20% of the final dilution should stem from the sample. 

Mode of action and kinetics. Routine polygalacturonase assays were performed in a reaction mixture containing 50 mM Na-acetate pH 4.2 and 0.25 % w/v pga at 30 °C. The release of reducing sugars was determined according to Stephens et al. [9]. For determination of pH optima the 50 mM Na-acetate buffer was replaced by Mcllvain buffers. 

Figure 5. pH activity profile of PGE on polygalacturonate. Mcllvaine buffers were used in the pH range from 2.5 to 5,5, Reducing sugars were detected by the neocuproine method. PGE (2 mg/ml) was 80-times diluted and incubated with 500 pi of a 0.25% (w/v) polygalacturonate solution, at SO C. 

Fish muscles Extraction with Mcllvaine buffer pH QL = 0.04 pg/g Recovery = 33-35% [78]... 

Extraction Mcllvaine buffer-EDTA solution, cleanup with SPE column... 

---