L-histidine doped CDs from Zingiber Montanum using hydrothermal method to enhance its antimicrobial activity and imply for latent fingerprint detection

Carbon dots (CDs) from Zingiber Montanum as a natural resource were prepared and tested as an antimicrobial activity with various types of bacteria. Then nitrogen doped carbon dots (N-CDs) were subject to obtain from the plant extract doped with L-histidine using hydrothermal method, indicating their N-CDs fluorescence intensity increases, and can be visualized more brightness under UV lamp compared with its bare CDs. Besides its antimicrobial purpose, fingerprint image is utmost known as one of the important characteristics of the crime evident, in this study, the N-CDs are then aimed to apply on various non-porous material surfaces for latent fingerprint detection. It was shown that the fine powder of N-CDs mixed with starch give more detailed minutiae compared with that from black commercial powder. The applicable fingerprint tracer using this N-CDs/starch powder shows a bit long time clear results until 90 days, indicating that the new N-CDs developed enhances much more the fingerprint performance than its usual. In addition, to confirm the antimicrobial activity the NCDs alone were also used for such antimicrobial testing via agarose disk diffusion assay against both gram negative and gram-positive bacteria, resulted satisfactorily that this nanomaterial can be a high potential use for antibacterial activity.