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The presence of chromium [Cr(VI)] and lead [Pb(II)] ions in the water bodies have adverse effects on humans and aquatic life. Graphene oxide-based magnetic nanocomposites synthesized in the presence of chitosan (mGO/CS) or polyaniline (mGO/PA) as potential adsorbents for the removal of Cr(VI) and Pb(II) ions. The FTIR (Fourier transform infrared spectroscopy), EDX (Energy dispersive X-ray), XRD (X-ray diffraction) and SEM (Scanning electron microscopy) were employed to investigate the chemical composition, structural, elemental analysis, crystalline size and morphology of the nanocomposites. The FTIR results confirmed the synthesis of the nanocomposites by detecting peaks of specific functional groups. The average crystallite sizes of the mGO, mGO/CS, and mGO/PA nanocomposites were 17, 25, and 23 (nm), respectively, as determined by the Debye-Scherrer equation from the XRD data. Batch adsorption experiments were conducted for Pb(II) and Cr(VI) removal by varying the variables like pH, concentration of metal ions and contact time. The Box Behnken design (BBD) was used to optimize the adsorption parameters. Under the optimum conditions, mGO/CS and mGO/PA showed maximum removal percentages (%R) of 92.36 and 98.7 for Pb(II), and 85.25 and 93.08 for Cr(VI), respectively. The adsorption capacities were 110.84 and 118.44 mg/g for Pb(II), and 87.74 and 111.7 mg/g for Cr(VI) were obtained for mGO/CS and mGO/PA, respectively. The pseudo-second-order kinetic model and Langmuir isotherm fitted well to the experimental data and explain the adsorption mechanism of the nanocomposite materials for both metal ions.

RESUMEN

Hydrogels are polymeric structures characterized by their three-dimensional nature, insolubility in aqueous media, and remarkable ability to absorb significant amounts of water. Owing to their exceptional biocompatibility with living tissues, hydrogels find extensive use in various biomedical applications. Guggul gum grafted polyacrylamide hydrogels (SG) were prepared and green synthesized SrO, CoO and SrO-CoO nanoparticles (NPs) were incorporated with hydrogels (SrG, CoG, Sr-CoG) respectively. The fabricated hydrogels were characterized by various analytical techniques such as FTIR, XRD and SEM. XRD results confirmed the presence of Sr and Co metal nanoparticles in the fabricated hydrogels matrix, SrG pattern showed diffraction peaks at 2θ = 30°, 36.59°, 44.11°, 50.22° and 62.20° while CoG peaks appeared at 2θ = 36.59°, 42.32°, 61.18°, 74.05° and 77.08°. SG, SrG, CoG and Sr-CoG hydrogels showed 11%, 32%, 23% and 45% radical scavenging activity respectively as compared to standard BHT (Butylated hydroxyl toluene). In vitro drug release tests results showed that SG, SrG, CoG and Sr-CoG exhibited 21%, 16%, 13% and 10% sustained release of naproxen respectively. The results revealed that SrO and CoO nanoparticles dopped hydrogels possessed good wound healing potential as compared to conventional hydrogels, which provides great potential in clinical treatment for wounds.

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The present study was conducted to appraise the anticancer activity of Pinus roxburghii essential oil along with chemical composition evaluation. MTT assay revealed cytotoxicity induction in colon, leukemia, multiple myeloma, pancreatic, head and neck and lung cancer cells exposed to essential oil. Cancer cell death was also observed through live/dead cell viability assay and FACS analysis. Apoptosis induced by essential oil was confirmed by cleavage of PARP and caspase-3 that suppressed the colony-forming ability of tumor cells and 50 % inhibition occurred at a dose of 25 µg/mL. Moreover, essential oil inhibited the activation of inflammatory transcription factor NF-κB and inhibited expression of NF-κB regulated gene products linked to cell survival (survivin, c-FLIP, Bcl-2, Bcl-xL, c-Myc, c-IAP2), proliferation (Cyclin D1) and metastasis (MMP-9). P. roxburghii essential oil has considerable anticancer activity and could be used as anticancer agent, which needs further investigation to identify and purify the bioactive compounds followed by in vivo studies.

RESUMEN

The sorption of Pb(II) and Cu(II) form aqueous media by Rosa bourbonia waste phyto-biomass (RBWPB) pretreated with organic acids was investigated as a function of biosorbent dosage, initial metal ions concentration and contact time. The equilibrium biosorption data was analyzed using two kinetic models (pseudo-first order and pseudo-second order) and two isotherm models (Langmuir and Freundlich). The RBWPB was successfully applied for sequestration of both heavy metal ions; however, organic acids pretreatments decreased the metal adsorption capacity of RBWPB. The Langmuir model fitted well to the data, and the pseudo-second order kinetic equation could best describe the biosorption kinetics of Pb(II) and Cu(II) metal ions. Gibbs free energy indicated the spontaneous adsorption of Pb(II) and Cu(II) onto RBWPB.

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