3-(4-Hydroxymethylphenylsulfanyl)propanoic acid (HMPPA) as a new safety catch linker in solid phase peptide synthesis

A new safety catch linker, 3-(4-hydroxymethylphenylsulfanyl)propanoic acid (HMPPA), is described for use in solid phase peptide synthesis. The linker is readily synthesized from commercially available chemicals in a more cost efficient way compared to similar reported linkers. The HMPPA linker is easily attached to an amino derivatized solid support followed by on-resin oxidation of the thioether to sulfoxide, thereby making the linker very stable towards strong acid treatment. Final resin cleavage is performed by reductive acidolysis.     

Optimization in sample stacking for the measurement of short chain organic acids in serum of natural rubber latex by capillary electrophoresis

It is of interest to measure the short chain organic acid content in natural latex serum, and capillary electrophoresis (CE) has proved to be a good tool for this study. However, for some acids, a higher sensitivity than that provided by the standard methods was needed. Therefore, a stacking effect was optimised and applied both for standards and real samples. Large-volume injection of sample solutions prepared in low conductivity matrices containing 50% acetonitrile (v/v) and 0.5% NaCl (w/v) gave the best results with enhancement factors over 17 and recoveries ranging from 83±14 to 122±4%.