A novel sample delivery method for powder X-ray diffraction at Turkish Light Source

Powder X-ray diffraction is highly sensitive to sample-delivery conditions, particularly when measurements are performed on platforms originally designed for single-crystal diffraction. In this study, we developed a modified Terasaki-plate-based sample-delivery method for PXRD using a laboratory single-crystal diffractometer implemented with the XtalCheck-S plate-reader module at Turkish Light Source. The method was evaluated against standard loop/pin-based loading and a grease-based Terasaki setup using [4-(2-methoxyphenyl)piperazin-1-yl]methyl}-1,3,4-oxadiazol-2-thiol as a model analyte. While the loop-based method allowed initial PXRD measurements, it provided limited sample volume and insufficient particle statistics. The grease-based plate setup enabled multi-well data collection at a time, but yielded weaker, more diffuse patterns due to increased background noise. Inversely, modification of the Terasaki wells with Kapton tape enabled secure low-volume powder loading, improved diffraction clarity, and supported batch-mode data collection. Comparative search-match and profile-fitting analyses showed that all three loading strategies sampled the same crystalline material, whereas the Kapton-based setup presented the most reliable diffraction profile, with the lowest profile residual (Rp = 9.6%). These findings indicate that this novel sample-delivery method, rather than instrument hardware, can largely improve PXRD performance on an existing in-situ crystallography platform. The Kapton-Terasaki method provides a simple, cost-effective, and practical pipeline for high-throughput PXRD analysis of small powder samples under laboratory conditions.