Improvement of Peak Shape in Analysis of Basic Compounds and Reduction of Carryover by Multi-Rinse Function

Introduction

Frequent hand disinfection is an effective measure against the spread of seasonal influenza. The main component of many hand disinfectants is ethanol, and some of them contain bactericidal components as well. The effective components in commercially-available disinfectants include chlorhexidine and benzethonium, both of which are strongly basic compounds. When basic compounds are analyzed with a typical C18 column, tailing or other deterioration of the peak shape may occur due to the nonspecific interaction with remaining silanol on the surface of the packing materials. Because the Shim-pack Arata™ C18 is especially designed to suppress the interaction with silanol, a good peak shape can be expected when analyzing basic compounds, even if using a simple composition of mobile phase. It is known that chlorhexidine is a compound that is extremely easily absorbed on the wetted parts of autosamplers, and for this reason, the results of subsequent analyses may be influenced by chlorhexidine carryover, particularly after analyzing a high concentration sample. The Nexera™ X3 system is equipped with multi-rinse function as a standard to reduce carryover by automatically rinsing the injection port, where carryover frequently occurs. This article introduces an analysis of the two abovementioned basic compounds using Nexera X3 and Shim-pack Arata C18, together with reduction of carryover by multi-rinse function.

July 8, 2020 GMT