Trace elements and components, used in chemical & engineering processes as catalysts and additives, play a crucial role in producing smooth and durable polymeric surfaces. The use of Sn as a catalyst is common for isocyanate reactions to form polyurethane films. However, a rapid quantification at PPM level for Sn presents a challenge. In this study we used electron microprobe (EMP) technique for in-situ analysis. The films containing varying concentrations of Sn (100-600 PPM) were analyzed by EMP in energy-dispersive (EDS) and wavelength-dispersive (WDS) modes. Sn was not detected using EDS analysis but the metal was resolvable at 500 PPM by WDS. However, WDS produced lower than expected abundances (385+43 PPM) due to inappropriate standardization. ICP-MS and ICP-OES analyses quantified Sn in all samples. This study reports our preliminary data, and further method development is in progress to improve standardization for EMP and development of a laser ablation ICP-MS technique.