Surface-enhanced Raman analysis of sulfa drugs on colloidal silver dispersion.

Surface-enhanced Raman spectrometry (SERS) of three sulfa drugs (sulfadiazine, sulfamerazine, and sulfamethazine) is reported. Silver colloidal dispersions prepared by simple borohydride reduction of silver nitrate are used as substrates. The capability of SERS for spectral fingerprinting of analytes with close structural properties using easily prepared substrates and relatively simple instrumentation is illustrated. By careful attention to the timing in the measurement, quantitative information can be obtained from silver colloids. Linearity was achieved up to 100 ng mL-1. Limits of detection range in the low nanograms per milliliter level.