This paper presents the synthesis and characterization of new thiosemicarbazone derivatives with potential applications as antibacterial, antioxidant and anticancer agents. Six thiosemicarbazone derivatives (L–L5) were synthesized by reacting an appropriate thiosemicarbazide derivative with 2-pyridinecarboxaldehyde. The structures of the obtained compounds were confirmed using mass spectrometry, infrared spectroscopy, and NMR spectroscopy. Antibacterial activity was evaluated by using the microdilution method, determining the minimum inhibitory concentration (MIC) against a panel of Gram-positive and Gram-negative bacteria. Compound L1 showed the most potent antibacterial activity, especially against Bacillus cereus (MIC 10 mg/L). Molecular docking to topoisomerase II and transcriptional regulator PrfA suggests that the studied compounds can effectively bind to molecular targets recognized in anticancer and antibacterial therapies. An assessment of physicochemical properties (ADME) indicates favorable parameters of the compounds as potential drugs. Compounds L and L2 showed the highest antioxidant activity, surpassing the activity of the Trolox standard. Cytotoxicity against A549 lung cancer cells was evaluated by the MTT assay. Compound L4 exhibited the strongest inhibitory effect on cancer cell survival. The obtained results indicate that the synthesized thiosemicarbazide derivatives, especially L1, L2, and L4, are promising compounds with potential applications as antibacterial and anticancer drugs.

The application of molecularly imprinted polymers (MIPs) as molecular scavengers for ambient plasma ionization mass spectrometry has been reported for the first time. MIPs were synthesized using methacrylic acid as functional monomer; nicotine, propyphenazone, or methylparaben as templates; ethylene glycol dimethacrylate as a cross-linker; and 2,2′-azobisisobutyronitrile as polymerization initiator. To perform ambient plasma ionization experiments, a setup consisting of the heated crucible, a flowing atmospheric-pressure afterglow (FAPA) plasma ion source, and a quadrupole ion trap mass spectrometer has been used. The heated crucible with programmable temperature allows for desorption of the analytes from MIPs structure which results in their direct introduction into the ion stream. Limits of detection, linearity of the proposed analytical procedure, and selectivities have been determined for three analytes: nicotine, propyphenazone, and methylparaben. The analytes used were chosen from various classes of organic compounds to show the feasibility of the analytical procedure. The limits of detections (LODs) were 10 nM, 10, and 0.5 μM for nicotine, propyphenazone, and methylparaben, respectively. In comparison with the measurements performed for the non-imprinted polymers, the values of LODs were improved for at least one order of magnitude due to preconcentration of the sample and reduction of background noise, contributing to signal suppression. The described procedure has shown linearity in a broad range of concentrations. The overall time of single analysis is short and requires ca. 5 min. The developed technique was applied for the determination of nicotine, propyphenazone, and methylparaben in spiked real-life samples, with recovery of 94.6–98.4%. The proposed method is rapid, sensitive, and accurate which provides a new option for the detection of small organic compounds in various samples. The experimental setup used for analysis