Fengping Miao

Synthesis and moisture absorption and retention activities of a carboxymethyl and a quaternary ammonium derivative of α,α-trehalose

Carboxymethyl alpha,alpha-trehalose (CMT) and a quaternary ammonium derivative of alpha,alpha-trehalose (QT) were successfully prepared, and their moisture absorption and retention activities were assessed. Results showed that both CMT and QT had better moisture absorption abilities at 43% and 81% relative humidity (RH) than alpha,alpha-trehalose. In addition, the two alpha,alpha-trehalose derivatives had better moisture retention abilities than alpha,alpha-trehalose under three humidity conditions: 81% RH, 43% RH, and under dry conditions. Therefore, carboxymethylation and quaternarization could improve the moisture absorption and retention abilities of alpha,alpha-trehalose. CMT and QT showed better moisture absorption ability and moisture retention ability than that of hyaluronan (HA), and could potentially find a use as moisture retention ingredient, for example, in cosmetics.

The Moisture Absorption and Retention Abilities of Hyaluronan, Chitosan, Starch and Their Quaternary Derivatives

Quaternary ammonium salt of hyaluronan (QHA), quaternary ammonium salt of starch (QS), and quaternary ammonium salt of chitosan (QCTS) were successfully prepared. Infrared spectroscopy (IR), 1H NMR and 13C NMR techniques were used to characterize the molecular structure of QHA. Results showed that QHA had better moisture absorption abilities than HA both at 43% and 81% RH. QS and QCTS had the same tendency. In addition, the three quaternized polysaccharides had better moisture retention abilities than their corresponding polysaccharides under three humidity conditions: 81% RH, 43% RH and dry condition. The -N+ (CH 3 ) 3 group played a very important role in moisture-absorption and retention ability of the quaternized polysaccharides. QCTS and QHA showed parallel or better R a and R h than that of HA, and had potential to use as moisture-retention ingredient, e. g., in cosmetics.

The Moisture Absorption and Retention Abilities of Quaternized Carboxymethyl Chitosan

Different types of quaternized carboxymethyl chitosans (QCMCs) were prepared in this study. The moisture absorption abilities of each QCMCs were measured at 81% and 43% relative humidity (RH), and the moisture retention abilities were done at 81% RH, at 43% RH and in silica gel. Hyaluronic acid (HA) was used as control in each condition. Results showed that, both at 81% and 43% RH, each QCMCs had better properties both in moisture absorption and retention than HA. And in silica gel, the moisture retention ability of each QCMCs was better than or close to that of HA. Therefore, it is hopeful that certain of the QCMCs would replace HA as the moisture absorption and retention ingredient in