McIlvain Buffers

An LC-thermospray MS assay was used for the determination of FZD in porcine tissue. Frozen pulverized tissue was homogenized with MeOH McIlvaine buffer, and the supernatant was extracted with dichloromethane. The organic layer, evaporated and reconstituted in... 

A sample (5g) was blended three times with 20, 20, and 10 mL of 0.1 M Na2EDTA-McIlvaine buffer (pH 4.0) using a high-speed blender and centrifuged each time. The supernatants were combined, centrifuged again, and filtered. 

Na2EDTA-McIlvaine buffer, filter, apply to cartridge, wash with 20 mL water, air dry under vacuum for 5 min. Condition a Baker 10 COOH cartridge with ethyl acetate. Elute contents of CIS cartridge onto COOH cartridge with 50 mL ethyl acetate. Wash COOH cartridge with 10 mL MeOH, elute with 10 mL mobile phase, inject a 100 p-L aliquot. 

This approach was used for the determination of OTC, TC, and CTC in milk samples. The centrifuged raw milk was mixed with succinate buffer (pH 4.0) to precipitate proteins. The clear supernatant was loaded directly on an MCAC column (1.5-ml Chelating Sepharose Fast-Flow) activated by passage of both water and 10 mM copper(II) sulphate solution. The blue-colored column was washed with both water and MeOH, and TCs were eluted with McIlvaine/EDTA/NaCl buffer. The extract was injected directly into the chromatographic system (25). 

The salt content of the buffer solutions of McIlvaine is rather high, and therefore the salt error of the indicator in these solutions will be much different from the error in other mixtures. 

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