微流蒸发光散射检测器的研制及评价

构建了适用于纳升级到微升级流量的毛细管分离体系的微流蒸发光散射检测器(μELSD),实现了其与毛细管液相色谱(eLC)的联用.对雾化器孔径和雾化毛细管内径、蒸发管内径和长度、光散射池尺寸、雾化毛细管位置和辅助载气流量等参数进行了优化.在最优条件下,微流蒸发光散射检测器检出限为直接进样葡萄糖1 ng(S/N＞ 10),线性范围0.01～1.0 μg,重复性好,峰面积RSD(n=6)为0.4％,峰高RSD(n=6)为0.3％.本检测器已成功应用cLC-μELSD平台,使用C18毛细管色谱柱(内径250 μm),0.1％甲酸铵溶液(pH 4.5)-甲醇(60∶40,V/V)为流动相,分离检测了3种常用甜味剂,表明本研究构建的系统可以应用于实际分离检测中,具有分析时间快、溶剂消耗量少、样品需求量小的优点.

Development and Evaluation of Micro Evaporative Light Scattering Detector

A novel micro-flow evaporative light scattering detector(μELSD),suitable for capillary liquid chromatography(cLC) system,was constructed and eveluated.The main parameters of detector,such as the aperture of nebulizer,inner diameter of capillary,specification of the evaporative tube and scattering cell,were optimized.Under the optimal experimental conditions:nebulizer 410 μm I.D.,nebulized capillary 50 μm I.D.×360 μm O.D.,evaporative tube 15 cm×4.6 mm I.D.,scattering cell 60 mm×33 mm I.D.,the detection limitation of glucose(S/N>10) was 1 ng with a linear range of 0.01-1 μg.Good reproducibility has been achieved in peak area and peak height with the RSD(n=6) of 0.4% and 0.3%(n=6),respectively.The detector was successfully coupled to a cLC system and applied to the separation and detection of three kinds of sweeteners,in the condition of capillary column(C18,250 μm I.D.) and 0.1%(V/V) ammonium formate(pH=4.5):methanol(60:40,V/V) as mobile phase.The cLC-μELSD system has the advantages in universal applicability,high column efficiency,and less solvent and sample consumptions compare with a common HPLC-ELSD system,and is suitable for separation and analysis of real samples.