Development of facile, on-spot, robust, and efficient optical nanosensors for drugs and pesticides is one of the active research area. In this study, a nanosensor based on fairly stable silver nanoparticles (AgNPs) conjugated with specially designed thiourea (TU)-based molecule, N-((4'-methoxy-2'-nitrophenyl) carbamothioyl) dodecanamide (TU3), was prepared using one pot protocol and characterized by Ultraviolet (UV)-Visible spectroscopy, dynamic light scattering (DLS), fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM). The TU3 conjugated AgNPs (TU3-AgNPs) were found to be selective spectrophotometric sensor for an antimicrobial drug, amlodipine (Ad), among the pool of different drugs. TU3-AgNPs based nanosensor allows for the rapid quantitative assay having a detection limit of 0.3 μM in an analytical range of 0.1-100 μM. The proposed sensor is specific in presence of number of other interfering drugs and other matrix. Upto the best of our literature survey, this is first ever colorimetric sensor for quantification of amlodipine in complex matrix. The specificity of the sensor allows for quantitative detection of amlodipine in environmental, biological and pharmaceutical samples.

The emergence of multidrug-resistant (MDR) pathogens and the gradual depletion of available antibiotics have exacerbated the need for novel antimicrobial agents with minimal toxicity. Herein, we report functionally substituted pyridine carbohydrazide with remarkable antimicrobial effect on multi-drug resistant strains. In the series, compound 6 had potent activity against four MDR strains of Candida spp., with minimum inhibitory concentration (MIC) values being in the range of 16–24 µg/mL and percentage inhibition up to 92.57%, which was exceptional when compared to broad-spectrum antifungal drug fluconazole (MIC = 20 µg/mL, 81.88% inhibition). Substitution of the octyl chain in 6 with a shorter butyl chain resulted in a significant anti-bacterial effect of 4 against Pseudomonas aeruginosa (ATCC 27853), the MIC value being 2-fold superior to the standard combination of ampicillin/cloxacillin. Time-kill kinetics assays were used to discern the efficacy and pharmacodynamics of the potent compounds. Further, hemolysis tests confirmed that both compounds had better safety profiles than the standard drugs. Besides, molecular docking simulations were used to further explore their mode of interaction with target proteins. Overall results suggest that these compounds have the potential to become promising antimicrobial drugs against MDR strains.

In search of anti-inflammatory compounds, novel scaffolds containing isonicotinoyl motif were synthesized via an efficient strategy. The compounds were screened for their in vitro anti-inflammatory activity. Remarkably high activities were observed for isonicotinates 5–6 and 8a–8b. The compound 5 exhibits an exceptional IC50 value (1.42 ± 0.1 µg/mL) with 95.9% inhibition at 25 µg/mL, which is eight folds better than the standard drug ibuprofen (11.2 ± 1.9 µg/mL). To gain an insight into the mode of action of anti-inflammatory compounds, molecular docking studies were also performed. Decisively, further development and fine tuning of these isonicotinates based scaffolds for the treatment of various aberrations is still a wide-open field of research.