Battersby J E, Guzzetta A W, Hancock W S
Genentech Inc., South San Francisco, CA 94080.
J Chromatogr B Biomed Appl. 1994 Dec 9;662(2):335-42. doi: 10.1016/0378-4347(94)00312-2.
Using capillary HPLC, femtomole amounts of recombinant DNA-derived human growth hormone (rhGH) have been successfully detected from solutions at nanomolar concentrations. The separation used capillaries of 15 cm x 320 microns I.D. and detection was with a UV absorbance detector containing a capillary Z-shaped flow-cell. A sample of rhGH that was recovered from rat serum was analyzed by capillary reversed-phase HPLC, using both acidic- and neutral-pH mobile phases, as well as by capillary ion-exchange chromatography. When compared to HPLC separations performed at flow-rates of 1 ml/min, the sensitivity of the detection was increased 200 times, without any loss in resolution. Sub-microgram amounts of rhGH were also analyzed by tryptic mapping using capillary HPLC and peptides were identified by capillary LC-MS.