Effect of various cryoprotectants on freeze-drying of liposomes containing Na methotrexate was written by Toliat, T.;Arab, N.;Rafiee-Tehrani, M.. And the article was included in Proceedings of the International Symposium on Controlled Release of Bioactive Materials in 1998.SDS of cas: 7413-34-5 This article mentions the following:
The retention of sodium methotrexate from liposomes after freeze-drying enhanced with the presence of sugars and polymers. Trehalose and Me cellulose had the most effective preservation against leakage form liposomes after lyophilization. In the experiment, the researchers used many compounds, for example, Sodium (S)-2-(4-(((2,4-diaminopteridin-6-yl)methyl)(methyl)amino)benzamido)pentanedioate (cas: 7413-34-5SDS of cas: 7413-34-5).
Sodium (S)-2-(4-(((2,4-diaminopteridin-6-yl)methyl)(methyl)amino)benzamido)pentanedioate (cas: 7413-34-5) belongs to amides. Because of the greater electronegativity of oxygen, the carbonyl (C=O) is a stronger dipole than the N–C dipole. The presence of a C=O dipole and, to a lesser extent a N–C dipole, allows amides to act as H-bond acceptors. Amides can be freed from solvent or water by drying below their melting points. These purifications can also be used for sulfonamides and acid hydrazides.SDS of cas: 7413-34-5
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics