Green synthesis and characterization of iron oxide nanoparticles using Coriandrum sativum L. leaf extract

Green nanoparticle synthesis is a promising, eco-friendly and safe approach. In the current study, Iron oxide nanoparticles (FeONPs) were synthesized using aqueous leaf extract of Coriandrum sativum L. Further, the characterization of synthesized FeONPs was performed using ultraviolet-visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), vibrating sample magnetometer (VSM) and differential scanning colorimetry (DSC). The surface plasmon resonance effect confirmed the synthesis of FeONPs. Dynamic light scattering (DLS) revealed mean particle size of FeONPs around 163.5 and polydispersity index 0.091 with a zeta potential of ?13.8 mV. Differential scanning colorimetry (DSC) exhibited an endothermic peak at 176.91°C. Vibrating sample magnetometer (VSM) analysis showed superparamagnetic properties of iron nanoparticles with a magnetization value of 3.483 emu/g and the results indicated superparamagnetic behavior of prepared iron nanoparticles at room temperature, thus highlighting their potential as magnetically targeted drug delivery system. This biosynthetic method has been proven to be cost-effective, environment friendly and promising for use in biomedical sciences.

Role of ATP-sensitive potassium channels in the piracetam induced blockade of opioid effects.

The present study has been designed to investigate the effect of piracetam on morphine/ buprenorphine-induced antinociception in rats and effect of piracetam on morphine or minoxidil induced relaxation in KCl-precontracted isolated rat aortic ring preparation. Nociceptive threshold was measured by the tail flick test in rats. The cumulative dose responses of morphine or minoxidil were recorded in KCl-precontracted isolated rat aortic ring preparation. Piracetam attenuated buprenorphine-induced antinociception in rats. Piracetam significantly reduced the morphine and minoxidil induced relaxation in KCl precontracted isolated rat aortic ring preparation suggesting that piracetam interferes with opioid receptor and ATP-sensitive potassium channel (KATP) opener mediated responses in vitro. Thus, it may be suggested that piracetam attenuates opioid effects by an opioid receptor-KATP channel linked mechanism.

Sildenafil improves acquisition and retention of memory in mice.

Sildenafil (Viagra) has been introduced recently in market to correct male impotency and has gained immense popularity for its dramatic effects all over the world. The present study was designed to investigate the effect of sildenafil on learning and memory in mice using elevated plus maze. A total of XV groups of animals were employed in the present study. Central cholinergic pathways play a crucial role in learning and memory processes. Physostigmine, an anticholinesterase agent (0.5 mg, 1.0 mg kg(-1), i.p) was employed for its memory enhancing property and alprazolam a benzodiazepine receptor agonist served as a memory-impairing agent. In the present study, alprazolam produced anterograde amnesia (at 0.5 mg kg(-1), i.p) and retrograde amnesia (at 0.25 mg, 0.5 mg, 0.75 mg kg(-1), i.p.) in separate groups of animals. Caffeine at 5 mg, 10 mg and 20 mg kg(-1), i.p. (an established psychostimulant) did not show any significant change in learning and memory of mice. Sildenafil (at 8 mg kg(-1), i.p.) administered 30 minutes prior to training on first day produced a marginal decrease in transfer latency time on first day; whereas, sildenafil (at 2 mg, 4 mg, 8 mg kg(-1), i.p.) administered immediately after training on first day produced a dose-dependent improvement of memory in mice. However, further studies need to be carried out to elucidate the underlying mechanism of sildenafil as a memory enhancer.