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Two novel fluorophore (BODIPY)-bearing complexes, pyriplatin (mCBP) and pyrimidine-chelated cisplatin (dCBP), were synthesized and characterized. The additional BODIPY-pyridine/pyridimine motifs of the two Pt(II) complexes resulted in stronger interactions with DNA in comparison with those of cisplatin. mCBP and cisplatin caused relative decreases in life span and body length in a cisplatin resistant in vivo model, N2 (wild-type) Caenorhabditis elegans. In contrast, dCBP resulted in a dramatic reduction in the two physiological parameters in N2 C. elegans, indicating high toxicity and sensitivity. The resistance factors (RF) of cisplatin, mCBP, and dCBP were determined to be 2.46, 1.04, and 0.91, respectively. The increasing RF folds for mCBP and dCBP against cisplatin were 2.36 and 2.70, respectively. This suggested they were featured with improved anti-chemoresistance capabilities. It is noteworthy that dCBP showed lowest lethal concentration (LC50) values of 0.56 and 0.61 mM in cisplatin resistant and sensitive in vivo models, respectively. Upregulation of several evolutionary conservation genes that regulate cisplatin chemoresistance through cisplatin effluxing, the DNA damage response, the unfolded protein response, and detoxification (asna-1, parp-1, enpl-1, and skn-1) was observed upon exposure to cisplatin but not to mCBP and dCBP. This could explain the improved anti-chemoresistance performances of synthesized Pt(II) complexes.

Carbon nitride quantum dots (CNQDs) were synthesized by the solid-phase method. The obtained CNQDs were characterized by XPS, TEM, FTIR and XRD. The results suggested that the CNQDs were ball-like nanoparticles (average diameter of 5 nm) with carboxyl and hydroxyl groups on the surface. The fluorescent emissions of the CNQDs were centered at 478 nm upon excitation with 365 nm UV light. The corresponding fluorescent quantum yield was measured as 32 %. The biocompatibility of the CNQDs with the model organism Caenorhabditiselegans (C. elegans) was systematically evaluated. The synthesized CNQDs enhanced the pharyngeal pumping rate, body length and life span of nematodes in a concentration-dependent manner after 24 h of exposure. Thus, the CNQDs affected the growth of the nematodes. The reproduction and motion capability indicators, including the egg laying rate and head thrash and body bend frequencies, were not influenced by the CNQDs. Therefore, the CNQDs did not show obvious toxicity to the C. elegans nematode model organism. The CNQDs could be taken up by nematodes, as characterized by fluorescence microscopy, proving that this material could be applied as a promising in vivo fluorescent imaging reagent.