An SPE-HPTLC method for simultaneous identification and quantification of seven pharmaceuticals in production wastewater was
optimized and validated. The studied compounds were enrofloxacine, oxytetracycline, trimethoprim, sulfamethazine, sulfadiazine,
sulfaguanidine and penicillin G/procaine. The method involves solid-phase extraction on hydrophilic-lipophilic balance cartridges
with methanol and HPTLC analysis of extracts on CN modified chromatographic plates followed by videodensitometry at 254 and
366 nm. Optimization of chromatographic separation was performed by systematic variation of the mobile phase composition using
genetic algorithm approach and the optimum mobile phase composition for TLC separation was 0.05 M H
2C
2O
4:methanol = 0.81:0.19 (
v/
v). Linearity of the method was demonstrated in the ranges from 1.5 to 15.0 µg L
−1 for enrofloxacine, 100–500 µg L
−1 for oxytetracycline, 150–600 µg L
−1 for trimethoprim, 300–1100 µg L
−1 for sulfaguanidine and 100–400 µg L
−1 for sulfamethazine, sulfadiazine and penicillin G/procaine with coefficients of determination higher than 0.991. Mean recoveries
ranged from 74.6 to 117.1% and 55.1 to 108.0% for wellspring water and production wastewater, respectively. Only sulfaguanidine
showed lower results. The described method has been applied to the determination of pharmaceuticals in wastewater samples
from pharmaceutical industry.
Keywords Thin layer chromatography - Videodensitometry - Veterinary pharmaceuticals - Wastewater treatment