IMPROVED ULTRAVIOLET DETECTION IN HIGH-TEMPERATURE OPEN-TUBULAR LIQUID-CHROMATOGRAPHY

Different ways to increase the sensitivity of UV detection in high-temperature open-tubular liquid chromatography are addressed. A micro flow (Z-shaped) cell was evaluated for the possibility of enhancing the signal-to-noise ratio in high-temperature open-tubular liquid chromatography. For the same chromatographic technique, a novel approach was taken with on-column detection. Optical fibre bundles were employed, yielding a significant increase in sensitivity with only a small decrease in efficiency. This approach is also feasible for other micro-separation techniques, e.g., capillary electrophoresis. Sample preconcentration and a gradient elution are also shown to be a powerful means of increasing detection limits in high-temperature open-tubular liquid chromatography.