低分子量羟丙甲纤维素的分子量及其分布的测定

Determination of the Molecular Weight and Its Distribution of Low Molecular Weight Hypromellose

摘要: 目的测定低分子量羟丙甲纤维素的分子量及其分布。方法利用高效体积排阻色谱-示差折光检测器-多角激光光散射检测器（HPSEC-RID-MALLS）技术，以0.1 mol·L^-1硝酸钠-甲醇（95：5）为流动相，采用Shodex OHpak SB-804 HQ（8.0 mm×300 mm）凝胶柱进行检测。结果低分子量羟丙甲纤维素的重均分子量测定误差≤2%，数均分子量和分子量分布误差均≤5%，结果准确可靠。结论利用HPSEC-RID-MALLS技术可测定低分子量羟丙甲纤维素的分子量及其分布。

Abstract: OBJECTIVE To determine the molecular weight and its distribution of low molecular weight hypromellose. METHODS High performance size exclusion chromatograghy in conjunction with refractive index detector and eighteen-angle laser light scatter detector(HPSEC-RID-MALLS), was performed on the Shodex OHpak SB-804HQ(8.0 mm×300 mm) column, using 0.1 mol·L^-1 sodium nitrate-methanol(95：5) as mobile phase. RESULTS The error of the weight-average molecular weight of low molecular weight hypromellose was ≤2%, and the error of number-average molecular weight and molecular weight distribution of low molecular weight hypromellose were ≤5%. The results were accurate and reliable. CONCLUSION It can be used to determine the molecular weight and its distribution of low molecular weight hypromellose by HPSEC-RID-MALLS．