Abramson M B, Katzman R
Science. 1968 Aug 9;161(3841):576-7. doi: 10.1126/science.161.3841.576.
Aqueous systems of sphingomyelin-sulfatide and lecithin-sulfatide were compared with aqueous systems of the individual lipids. The acid capacity of the mixed lipids increased, a result of the formation of an ionic bond between the sulfate of one molecule and the positive nitrogen of the other, making the phosphate available for direct titration. Cholesterol reduces this ionic interaction, probably because of the increased spacing of the ionized groups.
将鞘磷脂 - 硫脂和卵磷脂 - 硫脂的水相体系与单一脂质的水相体系进行了比较。混合脂质的酸容量增加，这是由于一个分子的硫酸盐与另一个分子的正氮之间形成了离子键，使得磷酸盐可用于直接滴定。胆固醇减少了这种离子相互作用，可能是因为离子化基团的间距增加。
