Although UV detectors are most commonly used in HPLC, refractive detectors are used when analysing compounds which do not possess UV absorption properties (such as sugars). When conducting sugar analysis using a refractive detector, baseline instability will generally become a problem. The most common reason for baseline drift problems is due to the changes in temperature of a column. Comparison of baseline stability for different temperature control methods is shown in the figures below. Baseline drift is very high at an ambient temperature without any column temperature control. Even when a water bath or a column oven is used, baseline noise can occur as a result of changes in temperature as a result of the heater switching on and off. One way to avoid this is to place the column in a stirred water bath at the ambient temperature without heating.

Comparison of baseline stability by a difference of a control method of column temperature.