High temperature injection in capillary high temperature liquid chromatography

A new high temperature sample introduction device for use in packed capilla ry high temperature liquid chromatography has been developed. In combinatio n with a commercially available high temperature injection valve, samples w ith little solubility in any solvent at ambient temperature could be analyz ed. Injections of synthetic high molecular weight hydrocarbon waxes were fe asible at elevated temperatures with the high temperature sample introducti on device. Compared to injection with a preheated conventional liquid chrom atography syringe, problems of precipitation and plugging were removed, the injection time was reduced, and the relative standard deviation of area me asurements was improved. The synthetic waxes could be separated with temper ature programming and isocratic mobile phases, with packed capillary column s and evaporative light scattering detection. (C) 1999 John Wiley & Sons, I nc.