On-line monitoring of process HPLC by sensors

On-line process control with a SAW (surface acoustic wave) sensor-based gas -sensor microsystem (SAGAS PC = surface acoustic wave based aroma and gas a nalyzing system) for industrial applications is presented. The monitoring o f the gradient former of a preparative HPLC system is a useful tool for the on-line process control of pilot plant production. All applications deal w ith the detection and subsequent qualification as well as quantitation of v olatile organic compounds (VOCs), for example, organic solvents or even wat er, by investigating their vapor with the SAGAS PC-system. To demonstrate t he suitability of the system for the above-mentioned purpose different exam ples of typical binary solvent mixtures for normal phase (NP) HPLC have bee n chosen. The accuracy, precision, and robustness of the applied method are determined, and the results meet the specification requirements. Furthermo re, online measurements in a pilot plant environment are presented.