Suzhou Yacoo Science Co. Ltd sell "PIPES"

PIPES buffer (piperazine-1,4-bis(ethanesulfonic acid), CAS 5625-37-6, molecular formula C8H18N2O6S2, molecular weight 302.36, 99.0-101% assay, white powder) has a pKa of 6.76 at 25C near physiological pH, useful for cell culture, with an effective buffering range of 6.1-7.5 at 25C. It has been shown to minimize lipid loss when buffering glutaraldehyde in plant and animal tissue histology, and combinations of glutaraldehyde and formaldehyde in PIPES buffer have optimized fungal zoospore fixation for fluorescence and electron microscopy. It has negligible divalent-ion binding capacity. Store at room temperature; packed in 25 kg drums or as requested.