High-Sensitivity Quantitative Analysis of Trace-Level Impurities and Active Ingredients with HPLC

As the trend toward smaller and smaller analyte concentrations progresses, conventional analytical methods are becoming less and less able to address trace-level analyses. For example, not only do product impurities affect product quality, there are increasing instances of product safety being compromised as well. This has prompted increasingly stringent impurity control across a wide range of business enterprises, where concern about quantitative analysis of extremely low levels of impurities is the current reality. On the other hand, when the analyte is the active ingredient itself, it becomes increasingly difficult to establish a quantitative method as the concentrations decrease to minute levels.
While the typical approach to addressing this situation is to increase sensitivity by taking such measures as increasing the sample concentration, there is always the concern that the solubility of the principal ingredient may be adversely affected, or that the analyte might not be sufficiently separated from possibly large numbers of obstructing substances in the sample matrix. Addressing this situation often necessitates the use of pretreatment procedures such as extraction and concentration, which also adversely affects efficiency due to the extra time and labor involved in conducting complicated pretreatment procedures.
Thus, it becomes necessary to satisfy two very different requirements for the quantitation of trace-levels of analytes: increasing measurement sensitivity and speeding up operations. The key point in achieving this is to automate the entire process from the fraction collection (fractionation) and concentration of the analytes to final quantitation.