Sensitive and rapid determination of elemental nanosulfur/sulfur by liquid chromatography.

ABSTRACT

In order to identify the most suitable method for the estimation of nanosulfur for studying its residue dynamics, the present work was taken up. HPLC and GC methods were explored for its analysis. A comparative study of the existing analytical methods for the quality control of nanosulfur was undertaken. UV spectrophotometry and HPLC methods were superior with lower LOD when compared to GC-MS, which was not satisfactory due to breakage of catenated S20 into S6 and S8 . The method has been validated by analyzing various nanosulfur formulations of known concentrations. The recovery of the UV and HPLC methods ranged from 80.71 to 109.51% and 82.31 to 109.84%, respectively. The LOD of UV, GC-MS, and HPLC is 4, 20, and 1 ppm, respectively. The retention time of sulfur was 13.77 (HPLC), 2.89 (ultra high performance liquid chromatography), and 12.715 + 21.524 min (GC-MS). The method was successfully utilized for estimating sulfur in natural samples such as water from a sulfur hot spring and wastewater. The method has been validated by following the method recommended by the American Society for Testing and Materials. The HPLC method emerged as the best analytical method for the estimation of elemental sulfur.