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Mesoporous bioactive glass demonstrated valuable biomedical applications especially in the field of bone regeneration and drug delivery. For the treatment of cancer by chemotherapy, controlled drug delivery system is one of the significant methods. In this work, silver oxide doped mesoporous bioactive glass nanoparticles (Ag2O-MBG NPs) were developed for the controlled release of doxorubicin as a model drug. Ag2O-MBG NPs were prepared by using the sol-gel method and employing pluronic 123 as an internal template. The prepared Ag2O-MBG NPs were characterized by energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for composition, shape, morphology, and size. Surface area and pore size were determined by the Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) method respectively. When immersed in simulated body fluid (SBF), hydroxycarbonate apatite (HCAp) formation was demonstrated as established by Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The as-synthesized Ag2O-MBG NPs did not show any detrimental effects during MTT assay and in vivo tissue histopathology. Doxorubicin (DOX) was encapsulated with an efficiency of 84% and its release was observed to be affected by the drug loading concentration (0.2–1.0 mg/mL) and pH (6.4–8.4) of the release media. DOX release was of 93% was witnessed approximately for two weeks at a slight acidic pH of 6.4. At 11.88 μg/mL of DOX-Ag2O-MBG NPs, notable inhibitory effects on the viability of the MG-63 osteosarcoma cancer cells were observed. These features proved that the Ag2O-MBG NPs system is effective for bone tissue regeneration and bone cancer treatment.

Mesoporous silica (MPS) and MPS-Fe composite was prepared via sol–gel technique and characterized by BET, FTIR, XRD, SEM and pZc. The MPS and MPS-Fe adsorption efficiencies were evaluated for a cationic dye Turquoise-blue X-GB. The MPS-Fe composite showed pore size and BET values of 9.52 nm and 309 m2/g, respectively. XRD and SEM analysis revealed the amorphous nature and uniform distribution of spherical partciles with average particle size of 50 nm of MPS-Fe composite. The points of zero (pZc) charge found to be 2.3 and 6.3 for MPS and MPS-Fe, respectively. The MPS and MPS-Fe showed promising efficiency for the adsorption of Turquoise-blue X-GB as a function of medium pH, contact time, dye initial concentration and temperature. Among, Freundlich, Langmuir, Harkins–Jura, Temkin, Doubinin–Radushkevich isotherms, the Turquoise-blue X-GB followed Langmuir isothermal model with adsorption capacities of 83.34 mg/g and 74.07 mg/g for MPS and MPS-Fe composite, respectively. Among kinetics models, pseudo second order kinetic model fitted to the dye adsorption with R2 values of 0.998 and 0.988 for MPS and MPS-Fe composite, respectively. The negative values of enthalpy (ΔH) and free energy (ΔG) revealed exothermic and spontaneous adsorption of dye at room temperature. Results revealed that MPS and MPS-Fe composite have promising potential for Turquoise-blue X-GB dye adsorption and could possibly be extended for the adsorption of dyes from textile effluents.

A simple approach to deposit metal chalcogenide-based quantum-dots on TiO2 (anatase) nanoparticles via pseudo-successive ionic layer adsorption and reaction (p-SILAR) was opted to design and investigate the corresponding photoactivity under visible light. We used TiO2/PbS and TiO2/CdS nanocomposites for photocatalysis after which we prepared solar paints from them to put side by side the resultant photovoltaic performance. We developed solar paint type quantum-dot-sensitized solar cells (QDSCs) from TiO2/PbS and TiO2/CdS nanocomposites to divulge electron-hole generation, electron-hole recombination, and resistance against photo-corrosion. TiO2/PbS exhibited higher electron-hole generation than TiO2/CdS owing to its efficient visible light harvesting capability which resulted in higher photocurrent density (JSC) and thus higher power conversion efficiency (PCE) for respective QDSC; however, it had inferior resistance against photo-corrosion. Additionally, the degradation of an azo-based dye (acid orange-56) reflected an effectual increase in the photocatalytic activity of anatase-TiO2 as a result of deposition of PbS and CdS QDs. TiO2/PbS performed better than TiO2/CdS as a photocatalyst under visible light irradiation.

In view of low cost and efficient adsorbents exploration, present study was aimed to evaluate the possibility of Pitpapra waste biomass (roots, leaves, stem) for adsorption of Zn (II) and Co (II) metals in single metal system (SMS) and binary metal system (BMS). The process variables were optimized for the maximum adsorption of metal ions. Pitpapra stem, leaves and root biomasses showed promising efficiency for the adsorption of Co (II) and Zn (II) ions and at optimized conditions of process variable, 225 mg/g and 230 mg/g of Co (II) and Zn (II) ions were removed from aqueous media, respectively. The behavior of Zn (II) in BMS changed, however, Co (II) did not show any change in BMS versus SMS. Freundlich isotherm fitted well to the adsorption data of Co (II) and Zn (II). In view of efficient adsorption of Co (II) and Zn (II) ions, the use of Pitpapra biomass is suggested for the adsorption of heavy metals from wastewater.

Owing to its excellent thermal and mechanical properties of graphene, graphene-based composites have attracted tremendous research interest in recent years. In particular, graphene with high thermal conductivity becomes an important and promising filler in composites for thermal management. This critical review focus on the recent advances in graphene-based composites with high thermal conductivity. After the introduction of thermal conductive mechanisms of graphene-based composites, the fabrication methods of graphene-based composites are summarized. Then we also discuss currently researches of various graphene-based composites such as graphene/thermoplastic composites and graphene/thermoset composites. Herein, the mechanisms, preparation, and properties of graphene-based composites are discussed along with detailed examples from the scientific literature and the guidance are provided on the fabrication of composites with high thermal conductivity.

Biodiesel is produced by transesterification of fatty acid methyl esters (FAME) from oleaginous microalgae feedstock. Biodiesel fuel properties were studied and compared with biodiesel standards. Qualitative analysis of FAME was done while cultivating mixed microalgae consortia under three concentrations of coal fired flue gas (1%, 3.0% and 5.5% CO2). Under 1% CO2 concentration (flue gas), the FAME content was 280.3 μg/mL, whereas the lipid content was 14.03 μg/mL/D (day). Both FAMEs and lipid contents were low at other CO2 concentrations (3.0 and 5.5%). However, mixed consortia in the presence of phosphate buffer and flue gas (PB + FG) showed higher saturated fatty acids (SFA) (36.28%) and unsaturated fatty acids (UFA) (63.72%) versus 5.5% CO2 concentration, which might be responsible for oxidative stability of biodiesel. Subsequently, higher cetane number (52) and low iodine value (136.3 gI2/100 g) biodiesel produced from mixed consortia (PB + FG) under 5.5% CO2 along with 50 mM phosphate buffer were found in accordance with European (EN 14214) standard. Results revealed that phosphate buffer significantly enhanced the biodiesel quality, but reduced the FAME yield. This study intended to develop an integrated approach for significant improvement in biodiesel quality under surplus phosphorus by utilizing waste flue gas (as CO2 source) using microalgae. The CO2 sequestration from industrial flue gas not only reduced greenhouse gases, but may also ensure the sustainable and eco-benign production of biodiesel.

Laser stimulation effect on L. siceraria seed mucilage, biochemicals and enzymatic activities during early growth stages were investigated. The laser density power of 1mW/cm2 for 3 and 5min treatments were performed and various responses i.e., seedlings mucilage, biochemical and enzymatic activities were studied. Laser treatment of L. siceraria seeds enhanced the biochemical as well as the enzymatic activities. TPC (total phenolic contents),TFC (total flavonoids contents), TSS (total soluble sugar), reducing sugar, proline contents, total soluble protein and nitrogen contents were recorded higher in laser treated groups versus control. Mucilage from L. siceraria seed coat was also characterized. The pre-sowing seeds were treated with laser radiation for 3 and 5min. TPC, TFC, proline contents, total soluble protein and nitrogenous compounds contents, ascorbic acid contents were recorded higher at 3min. The laser irradiation effect on TSS, hydrogen peroxide (H2O2), malondialdehyde (MDA) was insignificant versus control. The SOD (superoxide dismutase) and POD (peroxidase), AMY (amylase), CAT (catalase) activities were recorded higher for 5min laser treatment. Results revealed that He-Ne continuous wave-laser pre-sowing seed irradiation affected the seed coat mucilage, biochemical and enzymatic activities positively and this treatment could possibly be used to enhance the L. siceraria productivity. Future study will be focused on growth at later stages and yield characteristics of L. siceraria.

Heavy metals contamination is a global issue and is a severe threat to living organisms. Present study was designed to analyze heavy metals distribution in soil, forage, blood and milk from Livestock station, Khizerabad, Sargodha, Pakistan. Statistical analysis was performed to access the variation in metals concernments in different types of samples as well as variation among sampling seasons. The concentration of heavy metals varied significant ( P − 1 in soil, 0.93–10.26 mg L − 1 in blood and 0.93–10.26 mg L − 1 in milk sample and similar trend was observed in case of Co, Cd, Cr and Pb. Concentration of Cr in soil, forage, blood and milk was recorded within the permissible limits, whereas Co and Cd contents were beyond the permissible limits. Pb and Ni contents were within the permissible limits in soil and forage samples. In comparison to previous study conducted in adjoining areas, it was observed that the heavy metals in the environment have been increased, which might be serious threat to the soil, environmental and livings organisms.

A novel diamine 4-(4-aminophenoxy)butyl-4-aminophenyl ether (ABAE) was synthesized as a chain extender (CE) by a quick and facile method using microwave reactor. CE was used for the preparation of stimuli-responsive Polyurethane-urea elastomer (PUU) with the ratio of NCO/OH from 2 to 2.5. Synthesized PUU was characterized with the help of Fourier transform infrared spectroscopy (FTIR), derivative thermogravimetric analysis (DTG), and scanning electron microscopy SEM. PUU films were loaded with an anti-cancer drug “doxorubicin”. Drug release kinetics were studied in different solvents, at different pH values and with different NCO contents of PUU. The maximum of 45% cumulative drug release was observed in DMSO while the drug release increased with the decrease in pH and a maximum cumulative release of 47% was observed at acidic pH of 4.4. The minimum drug was released from the one, which was crosslinked with highest ratio (2.5) of NCO/OH. So, we can say that drug release can easily be adjusted under different conditions and environments with the help of these stimuli-responsive media.

Correction for ‘Magnetic mesoporous bioactive glass for synergetic use in bone regeneration, hyperthermia treatment, and controlled drug delivery’ by Muhammad Saif Ur Rahman et al., RSC Adv., 2020, 10, 21413–21419, DOI: 10.1039/C9RA09349D.

Dual functional, magnesium-doped mesoporous bioactive glass nanoparticles (Mg-MBG NPs) were prepared for bone regeneration and drug delivery. Template-assisted (F127) economical sol-gel method was used to prepare spherical Mg-MBG NPS of 65 ± 5 nm as determined by TEM. Different initial concentrations (0.1–0.5 mg/mL) of Mitomycin C (Mc) were used for loading to the Mg-MBG, and as a result, the variable amount of drug was loaded. Drug release was studied at different pH values (6.4, 7.4 & 8.4) of the release media which showed a maximum cumulative release of 89%, at a pH of 6.4. MTT assay indicated no significant cytotoxicity in normal human fibroblast (NHFB) cells and in vivo tissue histopathology revealed no damage to the cells. Mc loaded Mg-MBG NPs inhibited the MG-63 cancer cell viability at all concentrations and showed the IC50 value of 20.8 µg/mL. XRD and FTIR spectra confirmed the formation of hydroxycarbonate apatite (HCA) upon immersion in simulated body fluid (SBF). Thus biocompatible Mg-MBG with low cytotoxicity and sustained drug release was entitled as a safe biomaterial.

Solar red BA (SR-BA) and solar brittle blue A (SBB-A) direct dyes adsorption using Eucalyptus angophoroides bark (EAB) biomass was studied. The effect of process variables i.e., pH, contact time, particle size, temperature, initial dyes concentration, adsorbent dose and NaCl addition were investigated. The adsorption isotherms (Langmuir, Freundlich and Temkin), kinetics models (pseudo-first and pseudo-second-order) and thermodynamics parameters (ΔH°, ΔS° and ΔG°) were employed to evaluate the adsorption mechanism. Thermodynamic studies indicated the spontaneous and exothermic adsorption process of both dyes onto EAB. Maximum adsorptions of SBB-A and RR-BA onto EAB were 49 mg/g and (43.5 mg/g), respectively at 2 pH, 0.25 mm particle size, 303 K, 0.1 g adsorbent dose, 0.05 M NaCl, 25 mg/L dyes initial concentration and contact time 180 min (SBB-A) and 240 min (RR-BA). The SEM and FTIR studies of dye loaded and unloaded biomass were performed in order to check the surface morphology and functional group involved in dye adsorption. The optimized conditions were applied for the adsorption of dyes from textile wastewater and up to 65.4% ± 3.20 dye removal was achieved. Results indicated that the EAB could be an efficient and low cost adsorbent for the adsorption of dyes form textile effluents.

Vibrio fischeri bioluminescence inhibition bioassay (VFBIA) has been widely applied for the monitoring of toxicity on account of multiple advantages encompassing shorter test duration, sensitive, cost-effective and ease of operation. Moreover, this bioassay found to be equally applicable to all types of matrices (organic & inorganic compounds, metals, wastewater, river water, sewage sludge, landfill leachate, herbicides, treated wastewater etc.) for toxicity monitoring. This review highlights the apparent significance of Vibrio fischeri bioluminescence inhibition assay for ecotoxicological screening and evaluation of diverse chemical substances toxicity profile. The biochemical and genetic basis of the bioluminescence assay and its regulatory mechanism have been concisely discussed. The basic test protocol with ongoing improvements, widespread applications, typical advantages and probable limitations of the assay have been overviewed. The sensitivity of VFBIA and toxicity bioassays has also been compared.

Degradation and detoxification of petroleum refinery wastewater (PRW) was carried out by advanced oxidation processes (UV/TiO2/H2O2 and gamma radiation/H2O2). Response surface methodology (RSM) was used to optimize the independent variables. The cytotoxicity was evaluated using Allium cepa, brime shrimp and haemolytic assays; whereas mutagenicity was tested by Ames tests (TA98 and TA100 strains). Maximum reductions in COD and BOD were recorded as 78% and 87% for UV/TiO2/H2O2 and 77% and 86% for gamma ray/H2O2, respectively. Treatments with both methods at optimized conditions reduced the cytotoxicity and mutagenicity of PRW, however, UV/TiO2/H2O2 system was found slightly efficient as compared to gamma ray/H2O2. From the results, it can be concluded that AOP's can successfully be utilized for the degradation of toxic pollutants in petroleum refinery wastewater. Moreover, the bioassays used in this study offered a good reliability for checking the detoxification of treated and un-treated PRW wastewater.