Preparation and Characterization of Benzathine Penicillin G Solid Dispersions Using Different Hydrophilic Carriers

Several technical factors related to penicillin G intramuscular injection can affect its bioavailability and hence reduce the efficacy of rheumatic fever prevention program. When small amount of diluent is used, the powder is not completely dissolved and the thick suspension frequently causes obstruction of injection needle. The study aimed to characterize the solid-state properties of solid dispersion systems of benzathine penicillin G (BPG) prepared with hydrophilic carriers by applying solvent evaporation method. The results of spectroscopic studies; Fourier transform-infra red (FTIR), Nuclear Magnetic Spectroscopy (1HNMR) and Differential Scanning Calorimetry (DSC) revealed no chemical interaction between the drug and carriers. No significant changes in drug crystalline state were observed by X-ray diffraction and Scanning Electron Microscope (SEM) studies, even with using amorphous carriers; polyvinyl pyrrolidone (PVP-K30) and hydroxypropyl methylcellulose (HPMC). All the prepared solid dispersions demonstrated 76-93% yield and % drug content dependent on the polymer type and concentration. The hydrophilic polymers demonstrated potential effect on improving the flowability, wettability and dissolution characters of the drug. The results revealed that it is possible to enhance the dissolution rate of BPG (hydrophobic drug) by increasing the surface area of the drug adsorbed on the surface of hydrophilic polymer by solid dispersion method. Finally, solid dispersion BPG: PEG 4000 at ratio 50:50 gave uniform flowability of the powder (around 30), wettability (12 min) and faster dissolution rates among all the formulations. Thus, it was selected as the best formulation in this study

Preparation and Characterization of Benzathine Penicillin G Solid Dispersions Using Different Hydrophilic Carriers

Several technical factors related to penicillin G intramuscular injection can affect its bioavailability and hence reduce the efficacy of rheumatic fever prevention program. When small amount of diluent is used, the powder is not completely dissolved and the thick suspension frequently causes obstruction of injection needle. The study aimed to characterize the solid-state properties of solid dispersion systems of benzathine penicillin G (BPG) prepared with hydrophilic carriers by applying solvent evaporation method. The results of spectroscopic studies; Fourier transform-infra red (FTIR), Nuclear Magnetic Spectroscopy (1HNMR) and Differential Scanning Calorimetry (DSC) revealed no chemical interaction between the drug and carriers. No significant changes in drug crystalline state were observed by X-ray diffraction and Scanning Electron Microscope (SEM) studies, even with using amorphous carriers; polyvinyl pyrrolidone (PVP-K30) and hydroxypropyl methylcellulose (HPMC). All the prepared solid dispersions demonstrated 76-93% yield and % drug content dependent on the polymer type and concentration. The hydrophilic polymers demonstrated potential effect on improving the flowability, wettability and dissolution characters of the drug. The results revealed that it is possible to enhance the dissolution rate of BPG (hydrophobic drug) by increasing the surface area of the drug adsorbed on the surface of hydrophilic polymer by solid dispersion method. Finally, solid dispersion BPG: PEG 4000 at ratio 50:50 gave uniform flowability of the powder (around 30), wettability (12 min) and faster dissolution rates among all the formulations. Thus, it was selected as the best formulation in this study

Magnetic nanoparticles are highly toxic to chloroquine-resistant Plasmodium falciparum, dengue virus (DEN-2), and their mosquito vectors

SURESH KUMAR SUBBIAH (A04156) / / / Kadarkarai Murugan,Jiang Wei,Mohamad Saleh Alsalhi,Marcello Nicoletti,Manickam Paulpandi,Christina Mary Samidoss,Devakumar Dinesh,Balamurugan Chandramohan,Chellasamy Paneerselvam,Jayapal Subramaniam,Chithravel Vadiva

Appraising the therapeutical potentials of Alchornea laxiflora (Benth.) Pax & K. Hoffm., an underexplored medicinal herb: A systematic review

Ethnopharmacological relevance:Alchornea laxiflora (Benth.) Pax & K. Hoffm. (Euphorbiaceae) is an important traditional medicinal plant grown in tropical Africa. The stem, leaves, and root have been widely used in the folk medicine systems in Nigeria, Cameroon, South Africa, and Ghana to treat various ailments, including inflammatory, infectious, and central nervous system disorders, such as anxiety and epilepsy.Material and methods: The scientific name of the plant was validated using the “The Plant List,” “Kew Royal Botanic Gardens,” and Tropicos Nomenclatural databases. The literature search on A. laxiflora was performed using electronic search engines and databases such as Google scholar, ScienceDirect, PubMed, AJOL, Scopus, and Mendeley.Results: To the best of our knowledge, no specific and detailed review has been reported on A. laxiflora. Consequently, this review provides an up-to-date systematic presentation on ethnobotany, phytoconstituents, pharmacological activities, and toxicity profiles of A. laxiflora. Phytochemical investigations disclosed the presence of important compounds, such as alkaloids, flavonoids, phenolics, terpenoids, and fatty acids. Furthermore, various pharmacological activities and traditional uses reported for this botanical drug were discussed comprehensively.Conclusion: This systemic review presents the current status and perspectives of A. laxiflora as a potential therapeutic modality that would assist future researchers in exploring this African botanical drug as a source of novel drug candidates for varied diseases

Fabrication of nano-mosquitocides using chitosan from crab shells: impact on non-target organisms in the aquatic environment

Mosquitoes are arthropods of huge medical and veterinary relevance, since they vector pathogens and parasites of public health importance, including malaria, dengue and Zika virus. Currently, nanotechnology is considered a potential eco-friendly approach in mosquito control research. We proposed a novel method of biofabrication of silver nanoparticles (AgNP) using chitosan (Ch) from crab shells. Ch-AgNP nanocomposite was characterized by UV–vis spectroscopy, FTIR, SEM, EDX and XRD. Ch-AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi obtaining LC50 ranging from 3.18 ppm (I) to 6.54 ppm (pupae). The antibacterial properties of Ch-AgNP were proved against Bacillus subtilis, Klebsiella pneumoniae and Salmonella typhi, while no growth inhibition was reported in assays conducted on Proteus vulgaris. Concerning non-target effects, in standard laboratory considtions the predation efficiency of Danio rerio zebrafishes was 68.8% and 61.6% against I and II instar larvae of A. stephensi, respectively. In a Ch-AgNP-contaminated environment, fish predation was boosted to 89.5% and 77.3%, respectively. Quantitative analysis of antioxidant enzymes SOD, CAT and LPO from hepatopancreas of fresh water crabs Paratelphusa hydrodromous exposed for 16 days to a Ch-AgNP-contaminated aquatic environment were conducted. Notably, deleterious effects of Ch-AgNP contaminating aquatic enviroment on the non-target crab P. hydrodromous were observed, particularly when doses higher than 8–10 ppm are tested. Overall, this research highlights the potential of Ch-AGNP for the development of newer control tools against young instar populations of malaria mosquitoes, also highlighting some risks concerned the employ of nanoparticles in aquatic environments

Electrochemical Determination of Hydrogen Peroxide and Bicarbonate Using Peroxidase Activity of Copper, Zinc Superoxide Dismutase on Carbon Nanotube, Polypyrrole Nanocomposite Modified Pt Electrode

Measurement of hydrogen peroxide (H2 O2) and bicarbonate (HCO– 3) are essential in human pathology and pathophysiology as it provides valuable information with regard to signalling and prognostic of various diseases viz. oxidative stress and cardiovascular diseases. Therefore, we have developed here a novel electrochemical method for the determination of H2O2and HCO– 3 based on the peroxidase activity of copper, zinc superoxide dismutase (SOD). By immobilizing SOD onto the single walled carbon nanotubes (SWCNT)-polypyrrole (PPy) nanocomposite modified platinum electrode, the concentrations of H2O2and HCO– 3 were measured. The electrochemical behaviour of the SOD modified electrode was examined by cyclic voltammetry exhibiting characteristic quasi-reversible redox peak at the potential,+ 0.06 V versus Ag/AgCl. The peroxidase activity of SOD observed at –0.45 V was linear from 300 nM to 1 mM with a detection limit of 100 nM and sensitivity of 78.6 ± 1.7 nA μ M–1 cm–2. In the presence of HCO– 3, the peroxidase activity of SOD was enhanced linearly with HCO– 3concentration from 500 M to 50 mM. Based on this, we have measured here the HCO– 3 with a detection limit of 200 M and sensitivity of 1.23 μ A mM–1. Further, the concentrations of H2 O2 and HCO– 3 present in the human plasma samples were measured

Nanomaterial-based electrochemical biosensors for cytochrome c using cytochrome c reductase

Emerging evidences have pointed out that the release of cytochrome c (cyt c) from mitochondria into cytosol is a critical step in the activation of apoptosis. This article presents a novel approach for the detection of mitochondrial cyt c release for the first time using cytochrome c reductase (CcR) immobilized on nanoparticles decorated electrodes. Two kinds of nanomaterial-based biosensor platforms were used: (a) carbon nanotubes (CNT) incorporated polypyrrole (PPy) matrix on Pt electrode and (b) self-assembled monolayer (SAM) functionalized gold nanoparticles (GNP) in PPy-Pt. Scanning electron microscope was used to characterize the surface morphologies of the nanomaterial modified electrodes. Cyclic voltammograms of both the biosensors showed reversible redox peaks at − 0.45 and − 0.34 V vs Ag/AgCl, characteristic of CcR. In comparison, the CcR-CNT biosensor gave a detection limit of 0.5 ± 0.03 μM cyt c, which was 4-fold better than the CcR-GNP biosensor (2 ± 0.03 μM). Moreover, the CcR-CNT biosensor achieved a much larger linear range (1–1000 μM) over the CcR-GNP biosensor (5–600 μM) with 2-fold better sensitivity. The CcR-CNT-PPy-Pt biosensor was further applied to quantify the mitochondrial cyt c released in cytosol of A549 cells upon induction of apoptosis with doxorubicin, the results agreed well with standard western blot analysis