Ionic liquids have attracted many researches in bioactive compound separation as well as carbon capture. This is due to the ability of ionic liquid to be designed based on specific needs and produced higher quantity a...
Ionic liquids have attracted many researches in bioactive compound separation as well as carbon capture. This is due to the ability of ionic liquid to be designed based on specific needs and produced higher quantity and quality of extract product. A study showed that ionic liquid can extract a higher number of phytochemicals compared to conventional solvents and produce better yield with microwave-assisted extraction. Due to vast possible structures of ionic liquid and wide range of phytochemicals existed, a systematic approach was developed to screen ionic liquid solvents for phytochemical extraction. This study is a part of experimental validation included in the systematic approach. The main focus of this study is to optimize the process of ionic liquid-based microwave-assisted extraction of flavonoid and phenolic acid from Labisia pumila. A two-level, four-factor of central composite design (CCD) was employed to determine the effect of the process factors towards yield of flavonoid and phenolic acid extracted from the herb. The process factors are the temperature (Celsius), extraction time (min), power (W) and type of ionic liquid (based on their dielectric point). In this study, ionic liquid was back-extracted using organic solvents for regeneration and recycle of extraction solvent, based on Bogdanov (2015). The extracted samples were analyzed by determining the yield of flavonoid and phenolic acid through linear equation of quercetin and gallic acid. In this study, it can be observed that the recovery of flavonoid and phenolic acid from L. pumila using ionic liquid-based microwave-assisted extraction was about 30 – 50 percent higher compared to conventional solvent. Therefore, the study indicated that ionic liquid-based microwave-assisted extraction was an efficient and rapid method for L. pumila phytochemical extraction.
Electrocatalytic C−N bond coupling to convert CO 2 and N 2 molecules into urea under ambient conditions is a promising alternative to harsh industrial processes. However, the adsorption and activation of inert gas mol...
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Electrocatalytic C−N bond coupling to convert CO 2 and N 2 molecules into urea under ambient conditions is a promising alternative to harsh industrial processes. However, the adsorption and activation of inert gas molecules and then the driving of the C–N coupling reaction is energetically challenging. Herein, novel Mott–Schottky Bi-BiVO 4 heterostructures are described that realize a remarkable urea yield rate of 5.91 mmol h −1 g −1 and a Faradaic efficiency of 12.55 % at −0.4 V vs. RHE. Comprehensive analysis confirms the emerging space–charge region in the heterostructure interface not only facilitates the targeted adsorption and activation of CO 2 and N 2 molecules on the generated local nucleophilic and electrophilic regions, but also effectively suppresses CO poisoning and the formation of endothermic *NNH intermediates. This guarantees the desired exothermic coupling of *N=N* intermediates and generated CO to form the urea precursor, *NCON*.
Inspired by the dynamic morphology control of molecular assemblies in biological systems, we have developed pH‐responsive transformable peptide‐based nanoparticles for photodynamic therapy (PDT) with prolonged tumor...
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Inspired by the dynamic morphology control of molecular assemblies in biological systems, we have developed pH‐responsive transformable peptide‐based nanoparticles for photodynamic therapy (PDT) with prolonged tumor retention times. The self‐assembled peptide–porphyrin nanoparticles transformed into nanofibers when exposed to the acidic tumor microenvironment, which was mainly driven by enhanced intermolecular hydrogen bond formation between the protonated molecules. The nanoparticle transformation into fibrils improved their singlet oxygen generation ability and enabled high accumulation and long‐term retention at tumor sites. Strong fluorescent signals of these nanomaterials were detected in tumor tissue up to 7 days after administration. Moreover, the peptide assemblies exhibited excellent anti‐tumor efficacy via PDT in vivo. This in situ fibrillar transformation strategy could be utilized to design effective stimuli‐responsive biomaterials for long‐term imaging and therapy.
Improved understandings of two-phase transport in electrochemical gas-evolving systems are increasingly demanded, while high-performance imaging techniques using simplified instrumentations are not readily available. ...
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Carbon monoxide-releasing molecules (CORMs) are promising candidates for producing carbon monoxide in the mammalian body for therapeutic purposes. At higher concentrations, CO has a harmful effect on the mammalian org...
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Carbon monoxide-releasing molecules (CORMs) are promising candidates for producing carbon monoxide in the mammalian body for therapeutic purposes. At higher concentrations, CO has a harmful effect on the mammalian organism. However, lower doses at a controlled rate can provide cellular signaling for mandatory pharmacokinetic and pathological activities. To date, exploring the therapeutic implications of CO dose as a prodrug has attracted much attention due to its therapeutic significance. There are two different methods of CO insertion, i.e., indirect and direct exogenous insertion. Indirect exogenous insertion of CO suggests an advantage of reduced toxicity over direct exogenous insertion. For indirect exogenous insertion, researchers are facing the issue of tissue selectivity. To solve this issue, developers have considered the newly produced CORMs. Herein, metal carbonyl complexes (MCCs) are covalently linked with CO molecules to produce different CORMs such as CORM-1, CORM-2, and CORM-3, etc. All these CORMs required exogenous CO insertion to achieve the therapeutic targets at the optimized rate under peculiar conditions or/and triggering. Meanwhile, the metal residue was generated from i-CORMs, which can propagate toxicity. Herein, we explain CO administration, water-soluble CORMs, tissue accumulation, and cytotoxicity of depleted CORMs and the kinetic profile of CO release.
The effects of highly dispersed (≤ 0.1mg/cm2) noble metal catalysts (e.g. Pd, Pt, Ir and Ru) on the electrochemical performance of screen printed La0.84Sr0.16MnO3 cathodes was investigated. At typical operating condi...
The effects of highly dispersed (≤ 0.1mg/cm2) noble metal catalysts (e.g. Pd, Pt, Ir and Ru) on the electrochemical performance of screen printed La0.84Sr0.16MnO3 cathodes was investigated. At typical operating conditions (e.g. T=1273K, η= −0.1V), the current density in presence of palladium is increased by about one order of magnitude as compared to the current density obtained with pure La0.84Sr0.16MnO3 cathodes. At the same time, the apparent activation energy of the oxygen reduction reaction is decreased from ≈ 2eV (without catalyst) to ≈ 1eV (with Pd).
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