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Stimuli-responsive controlled drug delivery systems have attracted the attention of researchers in recent decades due to their potential application in developing efficient drug carriers that are responsive to applied stimuli triggers. In this work, we present the synthesis of L-lysine (an amino acid that combines both amine and carboxylic acid groups in a single unit) modified mesoporous silica nanoparticles (MS@Lys NPs) for the delivery of the anticancer bioactive agent (curcumin, Cur) to cancer cells. To begin, mesoporous silica hybrid nanoparticles (MS@GPTS NPs) with 3-glycidoxypropyl trimethoxy silane (GPTS) were synthesized. The L-lysine groups were then functionalized onto the mesopore channel surfaces of the MS@GPTS NPs through a ring-opening reaction between the epoxy groups of the GPTS and the amine groups of the L-lysine units. Several instrumental techniques were used to examine the structural properties of the prepared L-lysine-modified mesoporous silica nanoparticles (MS@Lys NPs). The drug loading and pH-responsive drug delivery behavior of MS@Lys NPs were studied at different pH levels (pH 7.4, 6.5, and 4.0) using curcumin (Cur) as a model anticancer bioactive agent. The MS@Lys NPs' in vitro cytocompatibility and cell uptake behavior were also examined using MDA-MB-231 cells. The experimental results imply that MS@Lys NPs might be used in cancer therapy as pH-responsive drug delivery applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The triphenylamine based two different π-conjugated heterocyclic polymers were prepared by Suzuki-coupling reaction. • The blue, red, and white emission obtained with the luminance of 6326, 4256, and 4596 cdm−2. • The novel method to achieve white light emission by simple method for the PLED manufacturing technology. The fine tuning of color and white light emission was achieved from the simple blending of two different types of polychromophores. The π-conjugated polymeric chromophores (blue and red) were synthesized and characterized for white light polymer emitting diode (WPLED) applications. The binary luminescent materials, Blue polymeric chromophore (BPy) and (Red polymeric chromophore (RPy), were obtained from the respective monomers via a standard Suzuki coupling reaction. The tuning of colors and white light emission were attained directly mixing of two polymeric chromophores (blue, red) in different ratio. The prepared polymer materials were confirmed using standard tehniques such as, Fourier transform infrared (FT-IR) and 13C and 1H-nuclear magnetic resonance (NMR) spectroscopy, while the gel-permeation chromatography result revealed the polymeric properties of the materials. The polymeric materials surfaces morphologies were analysed throught the FE-SEM and AFM analysis. The TGA (Thermogravymetric analysis) used to study the thermal property of the two prepared polymeric materials. The UV–visible and fluorescence spectrophotometry was applied to examine the optical features of the materials. The BPy and RPy polymers shows absorption peaks at 375 nm and 426 nm, respectively. The obatined emission peaks of BPy and RPy are at 426 nm and 603 nm, respectively. These results show that BPy and RPy belong to the blue and red emissive categories, and the white light emission was obtained with the mixing ratio of BPy(80%)-RPy(20%). The bandgap of these materials was calculated by cyclic voltammetry, and the theoretical bandgap of the materials was calculated by density functional theory analysis. Finely structured devices were fabricated, and the efficiencies of the BPy, RPy, and BPy-RPy were analyzed to assess the luminance productivity of the materials. In summary, this paper proposes a simple method to achieve white color emission by mixing polymeric chromophores at different ratios. [ABSTRACT FROM AUTHOR]

The present work is aimed at improving the efficiency of light-emitting diodes (LEDs) through the amalgamation of polymeric materials and quantum dots (QDs) in nanocomposites. Herein, we report on the polytriphenylamine-based chalcone (PTpC) or polycarbazole-based chalcone- (PCzC-) QDs mixture nanocomposites as emissive layers for polymer LEDs (PLEDs). QDs were evenly dispersed in the polymer matrix and the synthesized PTpC-QDs and PCzC-QDs nanocomposites were able to form smooth thin films. The luminance characteristics of PTpC-QDs and PCzC-QDs nanocomposites were better than those of the pristine QD, PTpC, and PCzC materials, owing to the high charge-carrier transport ability of polymer-QDs nanocomposites. These results indicate that the proposed polymer-QDs nanocomposites could be potential candidates for application in PLEDs. [ABSTRACT FROM AUTHOR]

Stimuli-response polymeric nanoparticles have emerged as a carrier system for various types of therapeutic delivery. In this study, we prepared a dual pH- and thermo-sensitive copolymer hydrogel (HG) system (PNIPAm-co-PAAm HG), using N-isopropyl acrylamide (NIPAm) and acrylamide (AAm) as comonomers. The synthesized PNIPAm-co-PAAm HG was characterized using various instrumental characterizations. Moreover, the PNIPAm-co-PAAm HG's thermoresponsive phase transition behavior was investigated, and the results showed that the prepared HG responds to temperature changes. In vitro drug loading and release behavior of PNIPAm-co-PAAm HG was investigated using Curcumin (Cur) as the model cargo under different pH and temperature conditions. The PNIPAm-co-PAAm HG showed pH and temperature-responsive drug release behavior and demonstrated about 65% Cur loading efficiency. A nearly complete release of the loaded Cur occurred from the PNIPAm-co-PAAm HG over 4 h at pH 5.5 and 40 °C. The cytotoxicity study was performed on a liver cancer cell line (HepG2 cells), which revealed that the prepared PNIPAm-co-PAAm HG showed good biocompatibility, suggesting that it could be applied as a drug delivery carrier. Moreover, the in vitro cytocompatibility test (MTT assay) results revealed that the PNIPAm-co-PAAm HG is biocompatible. Therefore, the PNIPAm-co-PAAm HG has the potential to be useful in the delivery of drugs in solid tumor-targeted therapy. [ABSTRACT FROM AUTHOR]

Superhydrophobic and superoleophilic polybenzoxazine-stearic acid based melamine sponge exhibiting an excellent oil/water separation property was fabricated by a facile route. The fabrication process involves the reduction and in situ polymerization of melamine sponge coated with benzoxazine and porous carbon/stearic acid. By employing this surface modification, the hydrophilic melamine sponge is converted into a superhydrophobic and superoleophilic material. The curing reactions occurring during the polymerization process are monitored by FT-IR and DSC analyses. Surface morphological studies have indicated that by producing hierarchically rough structures through low surface free energy polybenzoxazine, the surface composition of the melamine sponge can be tuned and its wettability can be interchanged as well. Furthermore, the modified melamine sponge exhibits fast and efficient oil/water separation and has excellent stability even after 20 cycles of usage. Therefore, this approach provides a new insight into the design and development of polybenzoxazine treated melamine sponge for industrial oil/water pollution treatments. [ABSTRACT FROM AUTHOR]

The therapeutic delivery system with dual stimuli-responsiveness has attracted attention for drug delivery to target sites. In this study, we used free radical polymerization to develop a temperature and pH-responsive poly(N-isopropyl acrylamide)-co-poly(acrylamide) (PNIPAM-co-PAAm). PNIPAm-co-PAAm copolymer by reacting with N-isopropyl acrylamide (NIPAm) and acrylamide (Am) monomers. In addition, the synthesized melamine-glutaraldehyde (Mela-Glu) precursor was used as a cross-linker in the production of the melamine cross-linked PNIPAm-co-PAAm copolymer hydrogel (PNIPAm-co-PAAm-Mela HG) system. The temperature-responsive phase transition characteristics of the resulting PNIPAM-co-PAAm-Mela HG systems were determined. Furthermore, the pH-responsive drug release efficiency of curcumin was investigated under various pH and temperature circumstances. Under the combined pH and temperature stimuli (pH 5.0/45 °C), the PNIPAm-co-PAAm-Mela HG demonstrated substantial drug loading (74%), and nearly complete release of the loaded drug was accomplished in 8 h. Furthermore, the cytocompatibility of the PNIPAm-co-PAAm-Mela HG was evaluated on a human liver cancer cell line (HepG2), and the findings demonstrated that the prepared PNIPAm-co-PAAm-Mela HG is biocompatible. As a result, the PNIPAm-co-PAAm-Mela HG system might be used for both pH and temperature-stimuli-responsive drug delivery. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanocarriers with dual/multifunctionalities are thought to be good candidates for dual/multimodal applications such as combined drug delivery and bioimaging. In this study, new red fluorescent organosilica materials were conveniently produced with diurea-ethidium bromide (DU-EB) functional units integrated in the pore wall framework for simultaneous diagnosis and therapy. We found that the prepared mesoporous silica hybrid nanocarrier system exhibited strong red fluorescence under UV-light (365 nm) while retaining excellent photo- and chemical-stability. The integrated ethidium bromide functional units in the mesopore walls cause the red fluorescence. By loading/releasing doxorubicin (Dox)/5-fluorouracil (5-FU) as a model cargo, the synthesized DU-EB@MSH materials were tested at various pH levels (pH 5.0, 6.2 and 7.4), and the cytocompatibility of the red-fluorescent DU-EB@MSH nanocarrier system was assessed using human breast cancer (MCF-7) cells. The experimental results revealed that the drug release behavior is primarily determined by the pH of the intracellular medium, and red-fluorescence was induced by a UV-light (365 nm) trigger. All the study results suggested that the DU-EB@MSH drug carrier system could be useful for red-fluorescence bioimaging and chemotherapeutic applications in cancer therapy. [ABSTRACT FROM AUTHOR]

• Kigelia Africana leaves synthesized and they are stably dispersed in deionized water. • Thermal properties of ACNMs – DI water based nanofluids was measured. • Convective heat transfer coefficient of an automobile radiator is reported. • 'Nu' and 'ff" are enhanced by rising ACNMs concentration and mass flow rate. The deionized (DI) water and activated carbon (AC) nanofluids were produced at different volume concentrations (VCs) such as 0.1, 0.25, and 0.4 %. ACNMs were produced through the pyrolysis process of deadly available Kigelia Africana leaves in a muffle oven at 500 °C. The structural properties of the activated carbon nanomaterials (ACNMs) were described through the usage of SEM, EDS, XRD, and FTIR analyzers. Thermal exchange properties that as density (ρ), thermal conductivity (TC), specific heat (SH), and viscosity (µ) of DI water - AC-based nanofluids were evaluated experimentally. The five various mass flow rates (MFRs) namely 20, 40, 60, 80, and 100 g/ sec were applied with different VCs of DI water - AC nanofluids in this study. In addition, the hot fluid (nanofluid) inlet temperature was constantly maintained with the help of a hot DI water bath at 50, 60, and 70 °C, respectively. The highest thermal conductivity (TC) augmentation attains up to 9.134 % is detected at 0.4 vol% of ACNMs loading at 70 °C. The addition of ACNMs augments the specific heat (SH) of the nanofluids substantially, and this augmentation diminutions with an increase in the ACNMs concentration. The addition of ACNMs in the DI water augments the Nusselt number by 21.76 %, 24.71 %, and 32.47 % for 50, 60, and 70 °C respectively, at a VCs of 0.4 % and mass flow rate of 0.1 kg/ sec in the car radiator. In addition, turn up a palpable reduction in Reynolds number for specified MFRs for all the ACNM nanofluids. [ABSTRACT FROM AUTHOR]

• Extracted Biofuel from the bio waste of Chicken shop by transesterification process. • Extracted Chicken waste oil (Biofuel) was enhanced with ZnO Nanoparticles. • BCW20/200ZnO Nanofuel exhibited 25% higher BTE than pure Diesel. • BCW20/100ZnO Nanofuel exhibited 13% higher BTE than pure Diesel. • SFC of BCW20/200ZnO and BCW20/100ZnO are 4% & 1% lesser than diesel. Microbial engineering is a new class of engineering that integrates the technologies of developing alternate fuels with chemical engineering and biotechnology. Clean technology-based research creates a high social impact and offers high benefits to society. This manuscript addresses the utilisation of biowaste from chicken shops for generating biofuel through transesterification and preparing Nano-fuels. The extracted biofuel was considered for preparing the B20 grade biodiesel, the biodiesel enhanced by mixing of ZnO nanoparticles (Nano-fuels). Through Ultrasonicator the B20 grade biodiesel mixed with ZnO (Zinc Oxide) Nanoparticles (50 Nano-meter (nm) average-sized) at two different concentrations. The proposed fuels like BCW20 biodiesel (20 %Chicken biowaste oil and 80 % Diesel), Nano-fuels (concentrations of 100 parts per million (ppm) and 200 ppm of ZnO nanoparticles) and tested these fuels in diesel engines to ensure its compatibility. The performance above said fuels were compared in terms of Brake Thermal Efficiency (BTE) and Brake Specific Fuel Consumption (BSFC), combustion performance by In-cylinder Pressure (ICP) and Heat Release Rate (HRR), and emission performance by emission of nitrogen oxides (NOx), Hydrocarbons (HC) and Carbon monoxide (CO). The comparative analysis revealed that 200 ppm ZnO nanoparticles concentrated Nano fuel outperformed by yielding 27 % higher BTE, proved economy by 4 % lesser BSFC, and also reduced NOx, HC, and CO emissions by 17 %, 7 %, and 11 %, respectively. The best operating condition is the use of BCW20 + 200 ZnO fuel, in particularly above 3.5KW of brake power (BP), the BSFC recorded less, at above 75 % load HC emissions found less and remaining other aspects there is no limitation in the use of recommended BCW20 + 200 ZnO fuel. [ABSTRACT FROM AUTHOR]

Treatment of recalcitrant and xenobiotic pharmaceutical compounds in polluted waters have gained significant attention of the environmental scientists. Antibiotics are diffused into the environment widely owing to their high usages, very particularly in the last two years due to over consumption during covid 19 pandemic worldwide. Quinolones are very effective antibiotics, but do not get completely metabolized due to which they pose severe health hazards if discharged without proper treatment. The commonly reported treatment methods for quinolones are adsorption and advanced oxidation methods. In both the treatment methods, metal organic frameworks (MOF) have been proved to be promising materials used as stand-alone or combined technique. Many composite MOF materials synthesized from renewable, natural, and harmless materials by eco-friendly techniques have been reported to be effective in the treatment of quinolones. In the present article, special focus is given on the abatement of norfloxacin and ofloxacin contaminated wastewater using MOFs by adsorption, oxidation/ozonation, photocatalytic degradation, electro-fenton methods, etc. However, integration of adsorption with any advanced oxidation methods was found to be best remediation technique. Of various MOFs reported by several researchers, the MIL-101(Cr)–SO 3 H composite was able to give 99% removal of norfloxacin by adsorption. The MIL – 88A(Fe) composite and Fe LDH carbon felt cathode were reported to yield 100% degradation of ofloxacin by photo-Fenton and electro-fenton methods respectively. The synthesis methods and mechanism of action of MOFs towards the treatment of norfloxacin and ofloxacin as reported by several investigation reports are also presented. [Display omitted] • Applications of metal organic framework for removal of pharmaceutical components are discussed. • Toxicological properties of norfloxacin and ofloxacin are presented. • Action mechanisms of MOFs in treatment of quinolones are explained. • Future scope and existing research gaps are identified. [ABSTRACT FROM AUTHOR]

• Novel MnCo(HPO 4) hexagonal tubes synthesized by CBD method. • Mn 0.5 Co 0.5 (HPO 4) exhibit high surface area of 132 m2 g−1. • Mn 0.5 Co 0.5 (HPO 4) shows a maximum specific capacitance of 1727 F g−1 at 1 A g−1. • AAS device could withstand 95.5% of its initial capacitance after 5000 GCD cycles. Novel bimetallic manganese-cobalt hydrogen phosphate (Mn x Co x (HPO 4)) hexagonal tubes were efficiently prepared by a direct and simple chemical bath deposition (CBD) procedure. The prepared Mn x Co x (HPO 4) materials have been analysed through Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) methods. The surface morphology and the particle size of the materials were studied using field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). The textural characteristics and elemental composition of the Mn x Co x (HPO 4) were measured using nitrogen sorption isotherms and X-ray photoelectron spectroscopy (XPS) analysis. Owing to its unique hexagonal structures and porous nature, the Mn 0.5 Co 0.5 (HPO 4) electrode is measured via a three-electrode system and achieved the highest specific capacitance of 1,727 F g−1 at the current density of 1.0 A g−1. An aqueous asymmetric supercapacitor (AAS), Mn 0.5 Co 0.5 (HPO 4)//G-ink device based on Mn 0.5 Co 0.5 (HPO 4) as the cathode and graphene ink (G-ink) as an anode material. The fabricated device might function well in a large operating potential window of +1.6 V. The Mn 0.5 Co 0.5 (HPO 4)//G-ink AAS exhibited the maximum power and specific energy of 9,000 W kg−1 and 56.16 Wh kg−1, correspondingly at 1.0 A g−1. Furthermore, the fabricated device could withstand 95.5% of its primary capacitance after 5,000 galvanostatic charge/discharge (GCD) turns, which illustrates that the materials could be a prominent contender for supercapacitor applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Supercapacitors store energy either by ion adsorption or fast surface redox reactions. The capacitance produced by the former is known as electrochemical double layer capacitance and the latter is known as pseudo-capacitance. Carbon materials are found to be attractive materials for energy storage, due to their various micro-structures and wide source of availability. Polybenzoxazine (Pbz) is used as a source to produce carbon materials, due to the fact that the obtained carbon will be rich in N and O species for enhanced performance. Moreover, the carbon materials were produced via template-free method. In general, activation temperature plays a main role in altering the porosity of the carbon materials. The main purpose of this study is to find the suitable activation temperature necessary to produce porous carbons with enhanced performance. Considering these points, Pbz is used as a precursor to produce nitrogen-doped porous carbons (NRPCs) without using any template. Three different activation temperatures, namely 700, 800 and 900 °C, are chosen to prepare activated porous carbons; NRPC-700, NRPC-800 and NRPC-900. Hierarchical micro-/ meso-/macropores were developed in the porous carbons with respect to different activation temperatures. PBz source is used to produce carbons containing heteroatoms and an activation process is used to produce carbons with desirable pore structures. The surface morphology, pore structure and binding of heteroatoms to the carbon surface were analyzed in detail. NRPCs produced in this way can be used as supercapacitors. Further, electrodes were developed using these NRPCs and their electrochemical performance including capacitance, specific capacitance, galvanic charge/discharge, impedance, rate capability are analyzed. The obtained results showed that the activation temperature of 900 °C, is suitable to produce NRPC with a specific capacitance of 245 F g−1 at a current density of 0.5 A g−1, that are attributed to high surface area, suitable pore structure and presence of heteroatoms. [ABSTRACT FROM AUTHOR]