Fast Release Research Articles

A biocompatible electrode/exoelectrogens interface augments bidirectional electron transfer and bioelectrochemical reactions

Bidirectional electron transfer is about that exoelectrogens produce bioelectricity via extracellular electron transfer at anode and drive cytoplasmic biochemical reactions via extracellular electron uptake at cathode. The key factor to determine above bioelectrochemical performances is the electron transfer efficiency under biocompatible abiotic/biotic interface. Here, a graphene/polyaniline (GO/PANI) nanocomposite electrode specially interfacing exoelectrogens (Shewanella loihica) and augmenting bidirectional electron transfer was conducted by in-situ electrochemical modification on carbon paper (CP). Impressively, the GO/PANI@CP electrode tremendously improved the performance of exoelectrogens at anode for wastewater treatment and bioelectricity generation (about 54 folds increase of power density compared to blank CP electrode). The bacteria on electrode surface not only showed fast electron release but also exhibited high electricity density of extracellular electron uptake through the proposed direct electron transfer pathway. Thus, the cathode applications of microbial electrosynthesis and bio-denitrification were developed via GO/PANI@CP electrode, which assisted the close contact between microbial outer-membrane cytochromes and nanocomposite electrode for efficient nitrate removal (0.333 mM/h). Overall, nanocomposite modified electrode with biocompatible interfaces has great potential to enhance bioelectrochemical reactions with exoelectrogens.

Simulation of emission of the flare 27.04.2012 in spectral lines of Hydrogen, Helium and Calcium

Тhe article is devoted to analyses of solar flare SOL2012-04-27 emission in Hydrogen, Helium and Calcium spectral lines observed on horizontal solar equipment HSFA-2 in Ondˇrejov observatory. The integrated fluxes are calculated. The data collected are treated in the approach of the fast energy release followed by gas evaporation. The gas parameters are calculated with chromosphere conditions and spectral line self-absorption taken into account. Encompassing of six lines allows to reveal the temperature, density and extent of the gas with high degree of validity. The best agreement of the theory with observations is obtained in the model of the spread of inhomogeneous clouds, each of which has hot (T ≈ 18000 ÷ 19500 K) and cool regions (T ≈ 8000 ÷ 9000 K). On average, one cloud gives about ten percent of the total flux.

Cinnamon oil-based self-emulsifying system for augmented dissolution and hypoglycemic efficacy of gliquidone

The aim was to formulate self-emulsifying drug delivery systems (SEDDS) to hasten dissolution and oral bioavailability of gliquidone (GLQ) as lipophilic oral hypoglycemic. In the developed formulations, cinnamon oil served as the oily phase, while Tween 20 and Transcutol® HP constituted the surfactant/cosurfactant system. A phase diagram was employed to select formulations showing transparent/translucent system after dispersion. These formulations were loaded with GLQ and subjected to in vitro dissolution studies relative to unprocessed GLQ. Optimum systems providing the fastest release were characterized for globule size and morphology. In addition, the in vivo hypoglycemic effect GLQ-loaded SEDDSs was assessed after oral administration to diabetic rats relative to GLQ aqueous dispersion (control). Optimized GLQ-loaded SEDDSs (3 formulations) displayed a significant improvement of dissolution rate as indicated from the amount dissolved after 5 min which recorded 72.83 %, 83.34 % and 92.38 %. Fast dissolution was parallel correlated with globule size values which were 335.4, 211.8 and 175.8 nm for the same formulations, respectively. Ultrafast dispersion and dissolution were revealed further in the in vivo hypoglycemic effect which was shown increasing the area under blood glucose reduction curve by 1.58, 1.61 and 2.11-fold after administration of the same formulation, compared with the control, respectively. Overall, the developed SEDDSs successfully enhanced both the dissolution rate and the bioavailability of GLQ.

A comparison between solvent casting and electrospinning methods for the fabrication of HPMC fast-dissolving films: investigation of the physicochemical, mechanical and drug release characteristics

The fast-dissolving film is an innovative dosage form that rapidly delivers the loaded drug upon contact with saliva. Many studies have been conducted on the fabrication of fast-dissolving films using hydroxy propyl methyl cellulose (HPMC) as a common film-forming agent with solvent-casting method or sometimes with electrospinning. However, there is no comparison of these two methods on the physicochemical, mechanical, and drug-release behavior of HPMC films. This paper aims to compare bisoprolol-containing fast-dissolving films composed of HPMC and polyethylene glycol (PEG) as plasticizer constructed by solvent-casting and electrospinning methods. Given the formulation parameters (e.g., plasticizer and polymer concentrations) and process parameters (e.g., tip-to-needle distance, voltage, and feed rate), various solvent-casting films and nanofiber mats were prepared. Films were characterized in terms of disintegration time, folding endurance, thermal behavior (using DSC), crystallin structure (using XRD), drug content, and drug release. The size and morphology of nanofibers were also evaluated by SEM. Solvent-casting film composed of 6% w/v HPMC and 6% v/v PEG400, as well as nanofiber mat composed of 13% w/v HPMC and 3% w/v PEG2000 were successfully constructed. DSC and XRD analysis revealed that the crystalline structure of bisoprolol converted into the amorphous structure in the polymeric films. Nanofibers were smooth and free of beads with a mean size of 0.66 ± 0.19 μm. In terms of flexibility, the nanofiber mats outperformed the solvent-casting films. The disintegration time of the nanofiber mat was less than that of the solvent-casting film (3 s versus 30 s). Besides, nanofibers indicated faster release. The superior performance of nanofiber mats can be attributed to their nanostructure. The results showed that the characteristics of the fast-dissolving films fabricated of HPMC, including disintegration time, release rate, and flexibility could be improved through the electrospinning process.

Statistical simplex centroid experimental design for evaluation of pectin, modified chitosan and modified starch as encapsulating agents on the development of vitamin E-loaded microparticles by spray-drying

Vitamin E encapsulation into biopolymer-based microparticles, obtained by spray-drying technology, was proposed to improve the encapsulation efficiency and the controlled release of fat-soluble vitamin. Binary and ternary blends of pectin, modified chitosan and modified starch, modified starch + modified chitosan, modified starch + pectin, modified chitosan + pectin and modified starch + modified chitosan + pectin ((0.33, 0.33, 0.33), (0.70, 0.15, 0.15), (0.15, 0.70, 0.15) and (0.15, 0.15, 0.70)) were proposed to produce and evaluate different carrier-based delivery systems. Vitamin E-loaded microparticles and empty microparticles were created with a product yield between 9 and 49 %. The mean diameter among all microparticles varied between 3.74 ± 0.02 and 421 ± 21 μm (differential volume distribution). Oval, spherical or irregular microparticles, with a variable morphology from a smooth to a high rough surface structure, with concavities, were produced. All vitamin E-loaded microparticles exhibited an encapsulation efficiency higher than 70 %. The slower vitamin E controlled release was observed from microparticles composed by modified chitosan (>36 h), while the faster release was achieved from microparticles individually composed by pectin (39 min). In general, the Fickian diffusion is the main release mechanism involved in the microparticles produced with modified chitosan, other formulations combine also other mechanisms such as swelling.

Enhancing Drug Delivery Efficacy Through Bilayer Coating of Zirconium-Based Metal-Organic Frameworks: Sustained Release and Improved Chemical Stability and Cellular Uptake for Cancer Therapy.

The development of nanoparticle (NP)-based drug carriers has presented an exciting opportunity to address challenges in oncology. Among the 100,000 available possibilities, zirconium-based metal-organic frameworks (MOFs) have emerged as promising candidates in biomedical applications. Zr-MOFs can be easily synthesized as small-size NPs compatible with intravenous injection, whereas the ease of decorating their external surfaces with functional groups allows for targeted treatment. Despite these benefits, Zr-MOFs suffer degradation and aggregation in real, in vivo conditions, whereas the loaded drugs will suffer the burst effect-i.e., the fast release of drugs in less than 48 h. To tackle these issues, we developed a simple but effective bilayer coating strategy in a generic, two-step process. In this work, bilayer-coated MOF NU-901 remained well dispersed in biologically relevant fluids such as buffers and cell growth media. Additionally, the coating enhances the long-term stability of drug-loaded MOFs in water by simultaneously preventing sustained leakage of the drug and aggregation of the MOF particles. We evaluated our materials for the encapsulation and transport of pemetrexed, the standard-of-care chemotherapy in mesothelioma. The bilayer coating allowed for a slowed release of pemetrexed over 7 days, superior to the typical 48 h release found in bare MOFs. This slow release and the related performance were studied in vitro using both A549 lung cancer and 3T mesothelioma cells. Using high-resolution microscopy, we found the successful uptake of bilayer-coated MOFs by the cells with an accumulation in the lysosomes. The pemetrex-loaded NU-901 was indeed cytotoxic to 3T and A549 cancer cells. Finally, we demonstrated the general approach by extending the coating strategy using two additional lipids and four surfactants. This research highlights how a simple yet effective bilayer coating provides new insights into the design of promising MOF-based drug delivery systems.

Sorafenib and Piperine co-loaded PLGA nanoparticles: Development, characterization, and anti-cancer activity against hepatocellular carcinoma cell line

Hepatocellular carcinoma (HCC) exhibits high mortality rates in the advanced stage (>90 %). Sorafenib (SORA) is a targeted therapy approved for the treatment of advanced HCC; however, the reported response rate to such a therapeutic is suboptimal (<3%). Piperine (PIP) is an alkaloid demonstrated to exert a direct tumoricidal activity in HCC and improve the pharmacokinetic profiles of anticancer drugs including SORA. In this study, we developed a strategy to improve efficacy outcomes in HCC using PIP as an add-on treatment to support the first-line therapy SORA using biodegradable Poly (D, L-Lactide-co-glycolide, PLGA) nanoparticles (NPs). SORA and PIP (both exhibit low aqueous solubility) were co-loaded into PLGA NPs (PNPs) and stabilized with various concentrations of polyvinyl alcohol (PVA). The SORA and PIP-loaded PNPs (SP-PNPs) were characterized using Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Powder Diffraction (XRD), Dynamic Light Scattering (DLS), and Scanning Electron Microscopy (SEM), Release of these drugs from SP-PNPs was investigated in vitro at both physiological and acidic pH, and kinetic models were employed to assess the mechanism of drug release. The in vitro efficacy of SP-PNPs against HCC cells (HepG2) was also evaluated. FTIR and XRD analyses revealed that the drugs encapsulated in PNPs were in an amorphous state, with no observed chemical interactions among the drugs or excipients. Assessment of drug release in vitro at pH 5 and 7.4 showed that SORA and PIP loaded in PNPs with 0.5 % PVA were released in a sustained manner, unlike pure drugs, which exhibited relatively fast release. SP-PNPs with 0.5 % PVA were spherical, had an average size of 224 nm, and had a high encapsulation efficiency (SORA ∼ 82 %, PIP ∼ 79 %), as well as superior cytotoxicity compared to SORA monotherapy in vitro. These results suggest that combining PIP with SORA using PNPs may be an effective strategy for the treatment of HCC and may set the stage for a comprehensive in vivo study to evaluate the efficacy and safety of this novel formulation using a murine HCC model.

Phospholipids Differentially Regulate Ca2+ Binding to Synaptotagmin-1.

Synaptotagmin-1 (Syt-1) is a calcium sensing protein that is resident in synaptic vesicles. It is well established that Syt-1 is essential for fast and synchronous neurotransmitter release. However, the role of Ca2+ and phospholipid binding in the function of Syt-1, and ultimately in neurotransmitter release, is unclear. Here, we investigate the binding of Ca2+ to Syt-1, first in the absence of lipids, using native mass spectrometry to evaluate individual binding affinities. Syt-1 binds to one Ca2+ with a KD ∼ 45 μM. Each subsequent binding affinity (n ≥ 2) is successively unfavorable. Given that Syt-1 has been reported to bind anionic phospholipids to modulate the Ca2+ binding affinity, we explored the extent that Ca2+ binding was mediated by selected anionic phospholipid binding. We found that phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and dioleoylphosphatidylserine (DOPS) positively modulated Ca2+ binding. However, the extent of Syt-1 binding to phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) was reduced with increasing [Ca2+]. Overall, we find that specific lipids differentially modulate Ca2+ binding. Given that these lipids are enriched in different subcellular compartments and therefore may interact with Syt-1 at different stages of the synaptic vesicle cycle, we propose a regulatory mechanism involving Syt-1, Ca2+, and anionic phospholipids that may also control some aspects of vesicular exocytosis.

Synthesis, Characterization and Drug Release Study of Novel Guided Tissue Regeneration Membranes Containing Drug Loaded Chitosan Nanoparticles

Periodontitis is an inflammatory disease which can cause the destruction of the supporting tissues of the tooth leading to tooth loss. The guided tissue regeneration is considered as a gold standard for its treatment but the re-infection of surgical site limits its overall success. Objective: To synthesize novel monolayer guided tissue regeneration (GTR) membrane containing drug loaded chitosan nanoparticles and to evaluate the drug release from the synthesized GTR membranes. Methods: The chitosan nanoparticles containing ciprofloxacin were synthesized by the ionotropic gelation method and these synthesized nanoparticles were added into chitosan GTR membrane fabricated by the freeze gelation method. For comparison GTR membrane was prepared as a control by freeze gelation method in which the drug was added directly. The prepared membranes were characterized by the SEM and FTIR. The drug release was measured from the membrane samples in the phosphate buffer saline (PBS) at 1, 3, 5, 7 and 9 days. Results: The GTR membrane containing the ciprofloxacin loaded chitosan nanoparticles showed fast drug release as compared to the membrane in which the ciprofloxacin was added directly. Conclusions: The inclusion of antibiotic loaded chitosan nanoparticles can increase the drug release from GTR membrane.

Internal Electric Field Facilitates Facet-Dependent Photocatalytic Cl- Utilization on BiOCl in High-Salinity Wastewater for Ammonium Removal.

High Cl- concentration in saline wastewater (e.g., landfill leachate) limits wastewater purification. Catalytic Cl- conversion into reactive chlorine species (RCS) arises as a sustainable strategy, making the salinity profitable for efficient wastewater treatment. Herein, aiming to reveal the structure-property relationship in Cl- utilization, bismuth oxychloride (BiOCl) photocatalysts with coexposed {001} and {110} facets are synthesized. With an increasing {001} ratio, the RCS production efficiency increases from 75.64 to 96.89 μg L-1 min-1. Mechanism investigation demonstrates the fast release of lattice Cl- as an RCS and the compensation of ambient Cl-. Correlation analysis between the internal electric field (IEF, parallel to [001]) and normalized efficiency on {110} (kRCS/S{110}, perpendicular to [001]) displays a coefficient of 0.86, validating that the promoted carrier dynamics eventually affects Cl- conversion on the open layered structure. The BiOCl photocatalyst is well behaved in ammonium (NH4+-N) degradation ranging from 20 to 800 mg N L-1 with different chlorinity (3-12 g L-1 NaCl). The sustainable Cl- conversion into RCS also realizes 85.4% of NH4+-N removal in the treatment of realistic landfill leachate (662 mg of N L-1 NH4+-N). The structure-property relationship provides insights into the design of efficient catalysts for environment remediation using ambient Cl-.

Solubility and Dissolution Enhancement of Candesartan Cilexetil by Complexation with Cyclodextrin

At present, numerous novel chemical compounds face challenges related to their limited solubility in aqueous environments. These compounds are classified under the Biopharmaceutical Classification System (BCS) as either class II or class IV substances. Different carriers were used to increase their solubility. Candesartan cilexetil (CC) is one of the most widely used antihypertensive drugs, which belongs to class II drugs. The aim of this research was to enhance the solubility and dissolution rate of CC through a complexation approach involving β-cyclodextrin and its derivatives, specifically hydroxypropyl beta cyclodextrin (HP-β-CD), methyl beta cyclodextrin (M-β-CD), and sulfonyl ether beta-cyclodextrin (SBE-β-CD), serving as complexing agents. This complexation process was investigated both with and without the inclusion of poloxamer 407 (PX407) as a hydrophilic polymer. The complex was prepared through a combination of grinding, kneading, and co-evaporation techniques. The resulting complex underwent characterization, including assessments of its percentage yield, drug content, solubility, and dissolution properties, as well as analyses using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and fourier transforms infrared spectroscopy (FTIR). The results revealed that, the complex prepared using 1:1 molar ratio of M -β-CD:CC in the presence of 5% w/w PX407 by co-evaporation method had the highest percentage yield (97%) with drug content of 98.5%, the highest solubility (0.052 mg/mL) and fastest release of drug within 45 minutes compared to the other methods. The FTIR, DSC, and XRD confirmed the development of a partial inclusion complex of an amorphous nature

A comprehensive study of negative bias temperature instability in MOS structures

We propose systematic experiments of Negative Bias Temperature Instability and a model of the threshold voltage during and after the stress. The stress conditions were varied as function of time, voltage, temperature. After the stress end, recovery was monitored for ten seconds. The model takes into account the activity of interface, bulk and border traps, clarifies each contribution during and after the stress and the hydrogen related mechanism. The fast release kinetics of border traps after the stress end is discussed, the entity of the threshold voltage recovery before measurement is calculated and its possible impact on the overall reliability assessment is discussed.

A flexible modulated pesticide release platform through poly(urethane-urea) microcapsules: effect of different crosslinkers compositions.

Polymeric microcapsules (MCs) have become an important issue and have attracted increasing attention because of their tunable physical and chemical properties. Diverse shell structures can confer multiple properties on MCs. Different polyols (1,4-butanediol and glycerin) and polyamines (triethylenetetramine and isophorondiamine) were selected as crosslinkers to obtain emamectin benzoate (EB)-loaded poly(urethane-urea) MCs (PU-MCs) by interfacial polymerization. The four obtained PU-MCs showed sphericity with different degrees of smoothness on their surfaces, and displayed a uniform size distribution ranging from 500 to 700 nm. Moreover, transmission electron microscopy showed that the shell thickness was roughly uniform, and was greatly influenced by the type and structure of the crosslinker. GI-MCs, prepared using glycerin and isophorondiamine, had the largest shell thickness. GT-MCs, obtained using glycerin and triethylenetetramine, had the highest encapsulation efficiency and drug-loading content, and BT-MCs, obtained using mixtures of 1,4-butanediol and triethylenetetramine, had the fastest release behavior. Thermogravimetric analysis revealed that the greater the degree of shell crosslinking, the higher decomposition temperature and the greater the thermal stability. A BT-MC suspension had the lowest viscosity and contact angle with the best wettability. Bioassay experiments showed that BT-MCs exhibited good insecticidal activity against Plutella xylostella larvae with a half-maximal lethal concentration of 4.19 mg/L. Furthermore, a BT-MC suspension showed good thermal and light stability, with potential applications in minimizing the toxicity of EB through sustained release. Various properties of EB-loaded PU-MCs were modulated through simple selection of different polyols and polyamines during fabrication, which might have an important role in constructing the pesticide delivery system and improving pesticide utilization. © 2024 Society of Chemical Industry.

Citric acid-induced photochemical behavior of Cr(III)-substituted ferrihydrite: Fe and Cr release, mineral transformation and reactive oxygen species generation

Cr(III)-substituted ferrihydrite (Fh-Cr(III)) is widespread in the surrounding environment of mining areas. Fh-Cr(III) is unstable and susceptible to the influence of environmental factors, such as dissolved organic matter (DOM) and light, so Cr species embedded in mineral crystal layers are likely to have more profound negative effects on the environment with the photochemical behaviors of minerals. However, the photochemical behaviors of Fh-Cr(III) in the presence of DOM remains poorly understood. For this reason, citric acid (CA) was chosen as the representative DOM to study its combined effects with visible light irradiation on Fh-Cr(III) dissolution and phase transition. The results showed that CA hindered the agglomeration of Fh-Cr(III) particles, thereby slowing the phase transition of Fh-Cr(III). However, CA exacerbated the release of Fe and Cr by maintaining Fh-Cr(III) under unstable crystal structure. Moreover, due to the occurrence of ligand-metal charge transfer (LMCT) in (CA)n-Fh-Cr(III) formed on the Fh-Cr(III) surface, the synergistic effect between CA and light irradiation greatly promoted the dissolution of Fh-Cr(III). In the mixed system of Fh-Cr(III) (3 g/L) and CA (5 mM) at initial pH 3.0, the maximum concentrations of TFe and TCr were 18.17 and 5.68 mg/L after 6 h of light reaction, which were 1.82 and 3.62 times of those in the corresponding system in the darkness. Meanwhile, the Fe(III)/Fe(II) cycling in solution and solid surfaces was affected by various reactive oxygen species (ROS) generated from the LMCT process, in which the photoproduced Fe(II) further accelerated Cr(III) dissolution under acidic solution. The fast release of Cr(III) may pose greater danger to the environment as the more toxic Cr(VI) can be easily formed through the oxidation of dissolved Cr(III). This work offers fresh insights into the migration and transformation of Cr elements in the natural environment.

Evaluating novel biodegradable polymer matrix fertilizers for nitrogen-efficient agriculture.

Enhanced efficiency fertilizers (EEFs) can reduce nitrogen (N) losses in temperate agriculture but are less effective in the tropics. We aimed to design a new EEF and evaluate their performance in simple-to-complex tests with tropical soils and crops. We melt-extruded urea at different loadings into biodegradable polymer matrix composites using biodegradable polyhydroxyalkanoate (PHA) or polybutylene adipate-co-terephthalate (PBAT) polymers with urea distributed throughout the pellet. These contrast with commercially coated EEF that have a polymer-coated urea core. We hypothesized that matrix fertilizers would have an intermediate N release rate compared to fast release from urea or slow release from coated EEF. Nitrogen release rates in water and sand-soil columns confirmed that the matrix fertilizer formulations had a more progressive N release than a coated EEF. A more complex picture emerged from testing sorghum [Sorghum bicolor (L.) Moench] grown to maturity in large soil pots, as the different formulations resulted in minor differences in plant N accumulation and grain production. This confirms the need to consider soil interactions, microbial processes, crop physiology, and phenology for evaluating fertilizer performance. Promisingly, crop δ15N signatures emerged as an integrated measure of efficacy, tracking likely N conversions and losses. The three complementary evaluations combine the advantages of standardized high-throughput screening and more resource-intensive and realistic testing in a plant-soil system. We conclude that melt-blended biodegradable polymer matrix fertilizers show promise as EEF because they can be designed toward more abiotically or more microbially driven N release by selecting biopolymer type and N loading rate.

Fission product release from spent nuclear UOX fuel dissolution: Comparison between anoxic and reducing conditions and impact of pH

Several clad segments from the same spent nuclear fuel rod were leached in a highly alkaline solution representative of the conditions expected in the current Belgian reference deep disposal design, and in presence of hydrogen. The results are compared with experiments that were conducted with clad and declad samples in a bicarbonate solution without presence of hydrogen. For the monitored radionuclides (238U, 90Sr, 137Cs, 129I, 99Tc), a fast initial release was observed. Afterwards, the release depended on the experimental conditions (medium, redox conditions) for uranium, strontium and technetium, but not for cesium and iodine. The cumulated released fractions were quantified at the end of the experiment.Graphical

Membranes and Synaptosomes Used to Investigate Synaptic GABAergic Currents in Epileptic Patients.

Among the most prevalent neurological disorders, epilepsy affects about 1% of the population worldwide. We previously found, using human epileptic tissues, that GABAergic neurotransmission impairment is a key mechanism that drives the pathological phenomena that ultimately lead to generation and recurrence of seizures. Using both a "microtransplantation technique" and synaptosomes preparations from drug-resistant temporal lobe epilepsies (TLEs), we used the technique of two-electrode voltage clamp to record GABA-evoked currents, focusing selectively on the synaptic "fast inhibition" mediated by low-affinity GABAA receptors. Here, we report that the use-dependent GABA current desensitization (i.e., GABA rundown, which is evoked by applying to the cells consecutive pulses of GABA, at high concentration), which is a distinguishing mark of TLE, is mainly dependent on a dysfunction that affects synaptic GABAA receptors. In addition, using the same approaches, we recorded a depolarized GABA reversal potential in synaptosomes samples from the human epileptic subicula of TLE patients. These results, which confirm previous experiments using total membranes, suggest an altered chloride homeostasis in the synaptic area. Finally, the lack of a Zn2+ block of GABA-evoked currents using the synaptosomes supports the enrichment of "synaptic fast inhibitory" GABAA receptors in this preparation. Altogether, our findings suggest a pathophysiological role of low-affinity GABAA receptors at the synapse, especially during the fast and repetitive GABA release underlying recurrent seizures.

Embedded iron and nitrogen co-doped carbon quantum dots within g-C3N4 as an exceptional PMS photocatalytic activator for sulfamethoxazole degradation: The key role of Fe[sbnd]N bridge

The covalent modification of graphite-phase carbon nitride (g-C3N4) by carbon quantum dots (CQDs) is a promising way to improve its photocatalytic performance. Although CQDs can act as charge mediator for electrons storage and transfer, it is crucial to construct efficient interfaces, which serves as active sites for tight connect with g-C3N4 and fast release of electrons. Herein, a novel iron and nitrogen co-doped carbon quantum dots (Fe, N-CQDs) assembled g-C3N4 composite (FNCCN) was constructed via FeN bridge by hydrothermal and thermal polymerization methods. The FNCNN rivaled popular nitrogen-doped carbon quantum dots (N-CQDs) combined with g-C3N4 composites for peroxymonosulfate (PMS) activation and degradation of sulfamethoxazole (SMX). The SMX degradation rate (0.0963 min−1) is 5.38 and 3.15 times higher than that of g-C3N4 and N-CQDs/g-C3N4. The characterization and DFT calculation results suggest that Fe, N-CQDs was successfully incorporated into carbon matrix of g-C3N4 via FeN covalent bond, which joints the two counterparts closely and creates electron transport channels for higher electrons transfer efficiency. The FeN coordinated structure promotes PMS reduction on Fe2+ of FeN sites for HO and SO4- production and expedited photo carries separation through Fe3+/Fe2+ cycling. In addition, the degradation efficiency, ROS identification, EPR test and degradation pathway of SMX was determined, and the intermediate toxicity of degradation products was predicted. This work constructed a tight atomic-level connection between hydrophobic g-C3N4 and hydrophilic CQDs, which improved an effective strategy for accelerating electron transport and efficient photocatalytic activation of PMS.

Effects of Seed Rate on Seed Multiplication Ratio, Seed Quality And Yield of Malt Barley Seed Classes Under Irrigated Conditions in Northwest Amhara

Field experiments were conducted to identify seed rate enhancing seed multiplication ratio, seed quality and yield on Ibone (174/03) malt barely variety performance in Koga district during 2019 and 2020 irrigation seasons. Three seed classes (breeder, pre-basic and basic seeds) and seed rates (40, 60, 80 and 100 kg.ha-1) were compared. The experimental design randomized complete block in factorial arrangement with three replications. Analysis of variance was showed that the interaction effect of seed class and seed rate was not significant (P&gt;0.05) for the parameters of days to maturity, plant height, spike length, seed yield, seed multiplication ratio and thousand seed weight. The study result depicted that seed rate had brought significant effect on the seed yield and multiplication ratio of malt barely. Results indicated that lower seed rates gave better seed multiplication ratio in the districts. Increasing seed rate from 40 to 80 kg.ha-1 has increased seed yield from 3356.1 kg.ha-1 to 3696.8 kg ha-1 though seed yield difference between seed rates of 60 and 80 kg.ha-1 was statistically non-significant (p&gt;0.05). Increasing seed rate from 40 to 60 kg.ha-1 has continuously improved seed yield from 3356.1 to 3592.1 kg.ha-1 in all seed class in the districts, but the difference was statistically non-significant. In conclusion, seed rates as low as 60 kg.ha-1 can be used at all seed classes to accelerate early generation seed multiplication within the fast track variety release program in Western Amhara Region.

Formulation and Evaluation of Capsule-in-Capsule Technology for Biphasic delivery of Glipizide

In the present research work, to formulation and evaluation of capsule-in-capsule technology for biphasic delivery of Glipizide. The advantages of fast releasing liquid-filled-capsules and slow release beads-filled-capsules were combined to meet the optimized requirements of our biphasic drug delivery system. Glipizide slow releasing beads were prepared by ionotrophic gelation method by using natural polymers like Sodium alginate, Pectin and were filled into a smaller capsule. Glipizide fast releasing liquid dispersion was prepared by using either Castor oil carriers and further prepared a glipizide emulsion. This fast releasing liquid and slow releasing beads-filled-capsule was further inserted into a bigger capsule body and Seal the capsule by hydro alcoholic solution. The various formulation batches were subjected to physicochemical studies, entrapment efficiency, drug content, in vitro drug release and stability studies. Interaction studies reveal that there was no interaction between drug and polymers employed in this study. The optimized capsule-in-a-capsule formulation released 22.65±0.74% of drug at the end of 30 min and 95.04±0.88% of drug at the end of 12h. The drug release profile of Glipizide capsule-in-a-capsule formulation fits well with Pepas model followed by zero order, first order and Korsemeyer-peppa’s model. Korsmeyer-Peppas model analysis indicated that the drug release followed non-Fickian transport mechanism. The stability results indicate that the various parameters of our optimized formulation are not affected on storage at 45°C/75%RH up to 4 months. Target of capsule-in-capsule drug delivery loading dose reaches therapeutic drug level in blood plasma for quicker onset of action and Maintenance dose which maintain an effective therapeutic level for prolong period. The prepared Glipizide biphasic cap-in-cap will be used for treatment of Diabetes.