对羟基苯甲酸酯的HPLC-ELSD分析

蒸发光散射检测器（ELSD）是一种通用的HPLC检测器，其检测原理基于光散射现象。在使用热去除挥发性流动相并用氮气喷射之后，当光照射到残留的非挥发性组分的颗粒上时发生散射。在检测部分中，LED被用作照射非易失性组件的光源，并且散射光被光电倍增器转换为电信号以测量强度。糖和脂肪通常使用折射率检测器或紫外线检测器的短波长范围进行测量，可以以更高的灵敏度和更稳定的基线进行测量。UASGOApplication Note 2/2Application NoteAnalysis of p-Hydroxybenzoate Esters by HPLC-ELSD Analysis of p-Hy droxybenzoate Esters by HPLC-ELSD An evaporative light scatteri n g detector (ELSD) is a universal detector for HPLC by employing the detection pr i nc i ple of l i ght scattering. Effluent f rom a column i s sprayed with N2 gas and then is heated for evaporative removal of volat i le mobile phase and then the light is irradiated on to the r esidual non-volati l e components to measure the light scattering. In the detection portion， LED is used as a l ight source for irradiating on to the non-volatile components and scattered l ight is transformed into an electric s i gnal by photomultiplie r to measure its inte n sity. Sugar and fat ， which had been usu a l l y measured using a refract i ve index detector or short wavelength range of a UV detector， can be measured with higher sensitivity and a more st a ble baseline us i ng ELSD. In this report， p-Hydroxybenzoic acid and p-Hydroxybenzoate esters (par a ben)， which are used as an ant is eptic for food， pharmaceutical Keyword ： paraben， C18 column， ELSD，p-Hydroxybenzoic acid， p-Hydroxybenzoate esters PU-20896 Experimental Equipment： Conditions： P u m p ： PU-2089 Autosampler：PU-2080 Column oven： CO-2060 Column： CrestPak C18S (4.6 mmlDx150 mmL， 5 pm) Eluent： Acetonitrile/Water(60/40) Flow rate： 1.0 mL/min Column temp.： 40°C ELSD condition： Nebulizer temp.： 30℃，Evaporator temp.： 30℃* Gas flow rate； 1.2 SLM Injection 10 pL volume： Standard sample： p-Hydroxybenzoic acid 0.05 mg/mL， p-Hydroxybenzoate esters 0.1 mg/ mL each in Acetonitrile Rega r ding Methyl 4-hydroxybenzoate a n d Ethy 4-hydroxyb e nzoate wh i ch ar e se m i-volat i le ma t erials ， the p eak he ight d e pe nd s on t he e vapo r a ti o n t empe r ature . Peak height ca n b e i ncreased by sett i ng a lowe r te m per a t u re . R esul t s and D i scuss io n Figu r e 1 s h ows the chr o m a t o g r a m of p -Hy d ro x y b e n z o i c acid an d p -Hy d r ox y b e n z o a t e e s t e r s F igu re 1. C hr o ma tog r am o f p-H y droxyb e n zoic a c i d an d p-Hyd ro x yb enz o ate e s t e r s.1： p -H y d ro x y b e n zoic a ci d ， 2： Met h yl 4-h y droxybenzoate， 3： Eth y l 4-h ydroxybenzoa t e， 4： Pro p yl 4-hydroxybe n zoate， 5：Bu t h y l 4-h yd r oxybe n zoa t e