Covalent Coupling Research Articles

Modification of micro-crystalline graphite and carbon black by acetone, toluene, and phenol.

The chemical interactions of two types of graphite and two types of carbon black (CB) with acetone, toluene, and phenol were studied in order to evaluate the influence of chemical treatment on the structure and morphology of the carbon phases. The experimental treatment of carbon phases was carried out at room temperature for 1 hour. The chemical and phase composition were studied by x-ray photoelectron (XP) and Raman spectroscopies, while the morphology and structure were determined by powder x-ray diffraction, as well as transmission electron microscopy techniques. To shed light on the most probable explanation of the observed results, we performed simulations and calculations of the binding energies of acetone, toluene, and phenol with model carbon phases: a perfect graphene sheet and a defective graphene sheet containing various structural defects (vacancies as well as zigzag and armchair edges). Simulations show that all non-covalent and most covalent coupling reactions are exothermic, with acetone coupling having the higher calorimetric effect. Based on the results of the simulations and the XP spectroscopy measurements, the probable reactions taking place during the respective treatments are outlined. The conducted studies (both theoretical and experimental) show that the treatment of graphite powders and CB with acetone, toluene, or phenol can be used as a preliminary stage of their modification and/or functionalization, including their conversion into graphene-like (defective graphene, reduced graphene oxide, and/or graphene oxide) phases. For example, the treatment of SPHERON 5000 with acetone significantly facilitates their subsequent modification with laser radiation to graphene-like phases.

Vacuum-assisted thermal bonding of β-cyclodextrin and its derivatives as chiral stationary phases for high-performance liquid chromatography

In this work, the vacuum-assisted thermal bonding method was proposed for the covalent coupling of β-cyclodextrin (β-CD) (CD-CSP), hexamethylene diisocyanate cross-linked β-CD (HDI-CSP) and 3, 5-dimethylphenyl isocyanate modified β-CD (DMPI-CSP) onto the isocyanate silane modified silica gel. Under vacuum conditions, the side reaction due to the water residue from the organic solvent, air, reaction vessels and silica gel could be avoided, and the optimal temperature and time of vacuum-assisted thermal bonding method were determined as 160°C and 3 h. These three CSPs were characterized by FT-IR, TGA, elemental analysis and the nitrogen adsorption-desorption isotherms. The surface coverage of CD-CSP and HDI-CSP on silica gel was determined as ∼0.2 μmol m−2, respectively. The chromatographic performances of these three CSPs were systematically evaluated by separating 7 flavanones, 9 triazoles and 6 chiral alcohols enantiomers under the reversed-phase condition. It was found that the chiral resolution ability of CD-CSP, HDI-CSP and DMPI-CSP was complementary to each other. Among them, CD-CSP could separate all 7 flavanones enantiomers with the resolution of 1.09–2.48. HDI-CSP had a good separation performance for triazoles enantiomers with one chiral center. DMPI-CSP showed excellent separation performance for chiral alcohol enantiomers, among which the resolution of trans-1, 3-diphenyl-2-propen-1-ol reached 12.01. Generally, the vacuum-assisted thermal bonding had been demonstrated as a direct and efficient method for the preparation of chiral stationary phases of β-CD and its derivatives.

Lipase-based MIL-100(Fe) biocomposites as chiral stationary phase for high-efficiency capillary electrochromatographic enantioseparation.

A novel chiral porous column was fabricated by lipase immobilized MIL-100(Fe) biocomposites as chiral stationary phase through covalent coupling and applied to capillary electrochromatographic enantioseparation. MOF-based lipase biocomposites not only enhance stereoselective activities but also improve the stability and applicability of the enzyme. The functionalized porous columns were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and powder X-ray diffraction. The performance of the porous column was evaluated by enantioseparating amino acid enantiomers, affording high resolution over 2.0. Besides, the enantio-resolutions of phenylephrine, phenylsuccinic acid, chloroquine, and zopiclone were also greater than 2.0. The relative standard deviations of run-to-run, intra-, and inter-day repeatability were within 4.0% in terms of resolution and retention time, exhibiting excellent stability of the column. Conceivably, the results show that MOF-based lipase composites as chiral stationary phase offer a highly efficient means for enantioseparation in capillary electrochromatography, attributing to the enhanced enantioselective activities of lipase by highly ordered frameworks.

Fe-Co spinel oxides supported UiO-66-NH2 derived zirconia/ N-dopped porous hollow carbon as an efficient oxygen reduction reaction electrocatalyst

The fuel cell is the best potential candidate to replace fossil fuels, which are a limited resource with severe environmental impacts that result in global warming and other more severe health issues. Developing a high-performing nonprecious electrocatalyst for oxygen reduction reaction (ORR) in the fuel cell is desirable but still a significant challenge. Herein, the uniform zirconia/N-dopped porous hollow carbon (ZrO2-N-C) with octahedral structure is derived from UiO-66-NH2 with not only abundant three-dimensional interconnected mesopores but also a high density of active sites. Zr-containing metal-organic framework is chosen due to the high stability and charge density, anti-toxicity, and small oxygen adsorption enthalpies of ZrO2 nanoparticles. The introduction of the SiO2 template during the synthesis of UiO-66-NH2 plays a crucial role in constructing controllable morphology, porosity, and components through the pyrolysis process. Furthermore, the synergic covalent coupling between metal oxide spinel (AB2O4) and nanocarbon effectively enhances the ORR catalytic activity. The substitution of an oxophilic metal (Fe) in Co3O4 spinel improves the electrocatalytic activity. The FeCo2O4/ES-ZrO2/NC catalyst exhibits a high catalytic activity toward ORR with an Eonset of − 0.18 V vs Ag/AgCl with a Fe/Co ratio of 3:1 in an alkaline electrolyte. The as-prepared FeCo2O4/NC exhibits not only high electrocatalytic activity but also good stability better than the Pt/C catalyst. The porosity, various valances of metals, high surface area, and N-doped C active sites are considered the main reasons for ORR's high catalytic activity.

Biofunctionalization of Porous Titanium Oxide through Amino Acid Coupling for Biomaterial Design.

Porous transition metal oxides are widely studied as biocompatible materials for the development of prosthetic implants. Resurfacing the oxide to improve the antibacterial properties of the material is still an open issue, as infections remain a major cause of implant failure. We investigated the functionalization of porous titanium oxide obtained by anodic oxidation with amino acids (Leucine) as a first step to couple antimicrobial peptides to the oxide surface. We adopted a two-step molecular deposition process as follows: self-assembly of aminophosphonates to titanium oxide followed by covalent coupling of Fmoc-Leucine to aminophosphonates. Molecular deposition was investigated step-by-step by Atomic Force Microscopy (AFM) and X-ray Photoemission Spectroscopy (XPS). Since the inherent high roughness of porous titanium hampers the analysis of molecular orientation on the surface, we resorted to parallel experiments on flat titanium oxide thin films. AFM nanoshaving experiments on aminophosphonates deposited on flat TiO2 indicate the formation of an aminophosphonate monolayer while angle-resolved XPS analysis gives evidence of the formation of an oriented monolayer exposing the amine groups. The availability of the amine groups at the outer interface of the monolayer was confirmed on both flat and porous substrates by the following successful coupling with Fmoc-Leucine, as indicated by high-resolution XPS analysis.

Covalent Coupled Sulfur-Deficient MoS2 Nanosheets on Carbon Nanotubes toward Polysulfide Catalytic Conversion in a Lithium Sulfur Battery

The lithium sulfur battery is an attractive energy storage device because of its high theoretical capacity and energy density, but its lifetime is seriously limited by the shuttle effect of polysulfides. Herein, a rational design of vertical MoS2 nanosheets anchored on conductive carbon nanotubes through Mo–O–C covalent coupling is proposed. In this composite, the strong chemical interaction ensures rapid charge transfer at interfaces, while the sulfur-deficient and metallic 1T phase-containing MoS2 enhances the affinity with polysulfides and accelerates the reaction kinetics of polysulfide conversion. Benefitting from these merits, the composite serves as a coating layer on the separator in the lithium sulfur battery, leading to the impressive electrochemical performance of the initial capacities of 1291 mA h g–1 at 0.5 C and 1330 mA h g–1 at 0.2 C. The battery also shows an enhanced cycling stability with a low capacity fading rate of 0.089% per cycle after 500 cycles at 0.5 C.

Advanced Zn-air batteries based on efficient and durable perovskite/dual-doped graphene bifunctional oxygen catalysts

Rechargeable Zn-air batteries (ZABs) are regarded as promising energy storage devices due to their high energy and power density, high safety and cost-effectiveness. Nevertheless, the practical application has been hampered by the sluggish kinetics of the oxygen reaction during the discharge and charge processes, respectively. Herein, La0.75Sr0.25 Fe0.5Mn0.5O3 (LSFMO) nanoparticles with a modified coprecipitation method possess high intrinsic activities. More importantly, the synergic covalent coupling between N/S dual-doped reduced graphene (NS-RGO) and LSFMO greatly improves the ORR and OER capabilities of novel perovskite/dual-doped graphene hybrid material (LSFMO@NS-RGO). The oxygen reduction reaction (ORR) activity (E1/2 of 0.806 V and n of 3.66) and oxygen evolution reaction (OER) activity (the Ej=10 of 1.672 V and overpotential of 442 mV) of LSFMO@NS-RGO are equivalent to the advanced Pt/C catalyst and RuO2 catalyst, respectively, thereby leading to excellent bifunctional property (ΔE = 0.86 V). Rechargeable ZABs deliver a fairly small charge-discharge voltage polarization (0.72 V). Besides, a rechargeable ZAB with flowing-electrolyte is constructed, which reveals considerably high reversibility and stability over 80 h, much improved over rechargeable ZAB in static electrolyte system. Such excellent results demonstrate that LSFMO@NS-RGO represents a new class of promising bifunctional catalysts for rechargeable ZABs.

Immobilization of Alcohol Dehydrogenase on Organofunctionalized Glass Beads and Comparative Studies: It’s Beneficial Uses

In this Research Study immobilization of Alcohol Dehydrogenase enzyme on glass beads was done. k-carrageenan is a natural polysaccharide like cellulose obtained from seaweeds. ADH was immobilized by Covalent coupling. Then for further study, various parameters like Thermostability , pH study, storage stability and Reusability were optimized and carried out the comparison studies. Furthermore, FTIR analysis was done to prove that the enzyme was immobilized on the support bead. And the application was done with 3 different fruit juices. i.e. sugarcane juice, pineapple juice, and watermelon juice. In addition, this study introduces a new achievement of the eco-friendly effect of immobilized enzyme.

Peptide-functionalized graphene oxide quantum dots as colorectal cancer theranostics

Colorectal cancer (CRC) accounts for approximately 10% of all new cancer cases worldwide with significant morbidity and mortality. The current imaging techniques are lacking diagnostic precision while traditional chemotherapeutic strategies are limited by their adverse side effects and poor response in advanced stages. Targeted nanoparticles (NPs) can specifically bind to surface antigens on cancer cells and provide effective delivery of diagnostic and chemotherapeutic agent. Placenta-specific protein 1 (PLAC-1) is overexpressed in CRC and can be used as a target for detection and treatment of the disease. The aim of this work was to develop a targeted nanotheranostic agent for early diagnosis and inhibition of the malignant progression and metastasis of CRC. Graphene oxide quantum dots (QD) were covalently labeled with a peptide (GILGFVFTL) having high affinity to PLAC-1. The covalent coupling between the QD and the peptide was confirmed using a series of physicochemical and morphological characterization techniques. Confocal microscopy was used to evaluate the uptake of QD and QD-P in HCT-29, HT-116 and LS-180 CRC cell lines. Selective targeting of antigen PLAC-1 overexpressed on HT-29 and HCT-116 cells was measured by immunofluorescence. Cell proliferation, cell invasion and extent of PLAC-1 expression in CRC cells after treatment with QD and QD-P were determined. The prepared QD-P showed a significant increase in targeting and specific uptake in cells expressing the antigen PLAC-1 compared to non-functionalized QD. Treatment with QD-P also increased the cell cytotoxicity, reduced the invasiveness of HT-29 and HCT-116 cells by 38% and 62%, respectively, and downregulated the expression of PLAC-1 by 53% and 33%, respectively. These results highlight the potential use of QD-P as a theranostic agent for the detection and treatment of CRC cells expressing the antigen PLAC-1.

Evaluation of covalent coupling strategies for immobilizing ligands on silica colloidal crystal films by optical interferometry.

Immobilizing ligands is a crucial part of preparing optical sensors and directly connected to the sensitivity, stability, and other characteristics of sensors. In this work, an ordered porous layer interferometry (OPLI) system that can monitor the covalent coupling process of ligands in real time was developed. Films of silica colloidal crystal (SCC), as optical interference substrates, were surface modified by three different reagents: chloroacetic acid, glutaric anhydride, and carboxymethyl dextran. Staphylococcus aureus protein A (SPA), the ligand, was immobilized on SCC films. The covalent coupling process of SPA and SCC films can be dynamically monitored by the OPLI system. In addition, the three different strategies were evaluated by comparing the efficiency of the sensors prepared by different methods for binding Immunoglobulin G (IgG). The glutaric anhydride-modified sensor offers apparent advantages in terms of bound IgG quantity and affinity. This system provides a simple and intuitive way to determine the efficiency of different covalent coupling strategies. Furthermore, the sensor covalently coupled with SPA also excels in the determination of IgG content in complex systems such as milk. At the same time, the covalent coupling gives the sensor the ability to be stored stably over time.

Covalency dominating Z-scheme perylene-dicarboximide@ZnIn2S4 organic-inorganic hybrids for overall water splitting

Exploring covalent coupling organic-inorganic hybrids (OIHs) is of great significance for improving photocatalysis. Herein, ZnIn2S4 nanosheets are anchored at the surface of high crystalline perylene-dicarboximide (HC-PDI) nanorods, generating Z-scheme HC-PDI@ZnIn2S4 (HPZ) OIHs for efficient overall water splitting (OWS). The unique hierarchical branching heterostructure of HPZ nanohybrids improve the specific surface area, pore diameter, pore volume, and visible-light-harvesting ability, which provides the basis for photocatalytic reaction. The strong covalent connection between HC-PDI and ZnIn2S4 provides a fast channel for charge transfer. Simulated calculation and in-situ analysis collectively prove that the unique electron transfers of hybridization and photoexcitation bring about (−)HC-PDI@(+)ZnIn2S4 internal interfacial electric field and Z-scheme heterojunction, respectively, further resulting in the transfer of water oxidation in ZnIn2S4 and the high-efficiency separation of photoexcited charges in the system. The optimized HPZ nanohybrid exhibit boosted visible-light-driven OWS activity (275.4 μmol g−1 h−1 for H2 evolution and 138.4 μmol g−1 h−1 for O2 evolution) and remarkable stability (40 h). This covalency dominating OIHs approach advances the exploration of OWS photocatalysts.

Efficient remediation of meropenem using Bacillus tropicus EMB20 β-lactamase immobilized on magnetic nanoparticles

Reducing antibiotic pollution in the environment in essential to preserve the effectiveness of the available antibiotics. In the present study, β-lactamase from Bacillus tropicus EMB20 was immobilized onto magnetic nanoparticles (Fe3O4) through covalent coupling method. The nanoconjugate was structurally characterized using SEM, FTIR, UV-spectrometry, and XRD diffraction analyses. The prepared enzyme nanoconjugate was thereafter used for remediation of meropenem (Mer) and showed complete removal of 10 mgL−1 Mer within 3 h of treatment. Moreover, the immobilized enzyme was successfully recovered and reused for up to 5 cycles with 57% removal efficiency. The immobilized preparation was also observed to be effective in the removal of higher Mer concentrations of 25 and 50 mgL−1 with 79% and 75% removal efficiency, respectively. The major hydrolyzed product of Mer was found to be opened-lactam ring structure with m/z 402.16. The hydrolyzed product(s) were observed to be non-toxic as revealed through microbial MTT, confocal microscopy, and growth studies. Under the mixed conditions of 50 mgL−1 ampicillin (Amp), 10 mgL−1 amoxicillin (Amox) and, Mer, the nanoconjugate showed simultaneous complete removal of Amp and Mer, while 49% Amox removal was detected after 3 h of treatment. Moreover, the nanoconjugates also showed concomitant complete removal of antibiotic mixture with in 2 h from aquaculture wastewater. Overall, the study comes out with an efficient approach for remediation of β-lactam antibiotics from contaminated systems.

COF-Based Electrodes with Vertically Supported Tentacle Array for Ultrahigh Stability Flexible Energy Storage

As an emerging porous crystal polymer, covalent organic frameworks (COFs) possess unique characteristics, such as high porosity, excellent stability, diverse topologies, designable open channels, and functional tunability. However, limited by the solid powder form, most COFs display low active site utilization and weak binding force with the current collector. In this pioneering research, we integrate redox-active COFs onto carbon fiber surfaces (AC-COFs) via strong covalent bridging. The 2,6-diaminoanthraquinone (DAAQ) pillars embedded on the carbon fiber surface are the key to precisely controlling the growth direction of COFs. The obtained tentacle-like array vertically supported on the surface of the carbon fiber can effectively induce charge transfer and prevent COFs from aggregating/collapsing. The strong covalent coupling and increase of accessible active sites contributed to the high specific capacitance of AC-COFs electrode (1034 mF cm-2). In addition, the COF-based flexible electrode retains an initial capacitance of 98% after 20000 charge-discharge cycles. The flexible all-solid-state symmetric supercapacitor is assembled by PVA/H2SO4 gel electrolyte with an areal capacitance of 715 mF cm-2. Besides, a red LED can be easily powered by three-bending AC-COFs//AC-COFs devices. The innovative synthesis strategy opens up new opportunities to develop high-performance flexible energy storage devices based on COFs.

Advanced EPI-X4 Derivatives Covalently Bind Human Serum Albumin Resulting in Prolonged Plasma Stability

Advanced derivatives of the Endogenous Peptide Inhibitor of CXCR4 (EPI-X4) have shown therapeutic efficacy upon topical administration in animal models of asthma and dermatitis. Here, we studied the plasma stability of the EPI-X4 lead compounds WSC02 and JM#21, using mass spectrometry to monitor the chemical integrity of the peptides and a functional fluorescence-based assay to determine peptide function in a CXCR4-antibody competition assay. Although mass spectrometry revealed very rapid disappearance of both peptides in human plasma within seconds, the functional assay revealed a significantly higher half-life of 9 min for EPI-X4 WSC02 and 6 min for EPI-X4 JM#21. Further analyses demonstrated that EPI-X4 WSC02 and EPI-X4 JM#21 interact with low molecular weight plasma components and serum albumin. Albumin binding is mediated by the formation of a disulfide bridge between Cys10 in the EPI-X4 peptides and Cys34 in albumin. These covalently linked albumin-peptide complexes have a higher stability in plasma as compared with the non-bound peptides and retain the ability to bind and antagonize CXCR4. Remarkably, chemically synthesized albumin-EPI-X4 conjugates coupled by non-breakable bonds have a drastically increased plasma stability of over 2 h. Thus, covalent coupling of EPI-X4 to albumin in vitro before administration or in vivo post administration may significantly increase the pharmacokinetic properties of this new class of CXCR4 antagonists.

Convenient site-selective protein coupling from bacterial raw lysates to coenzyme A-modified tobacco mosaic virus (TMV) by Bacillus subtilis Sfp phosphopantetheinyl transferase

A facile enzyme-mediated strategy enables site-specific covalent one-step coupling of genetically tagged luciferase molecules to coenzyme A-modified tobacco mosaic virus (TMV-CoA) both in solution and on solid supports. Bacillus subtilis surfactin phosphopantetheinyl transferase Sfp produced in E. coli mediated the conjugation of firefly luciferase N-terminally extended by eleven amino acids forming a ‘ybbR tag’ as Sfp-selective substrate, which even worked in bacterial raw lysates. The enzymes displayed on the protein coat of the TMV nanocarriers exhibited high activity. As TMV has proven a beneficial high surface-area adapter template stabilizing enzymes in different biosensing layouts in recent years, the use of TMV-CoA for fishing ybbR-tagged proteins from complex mixtures might become an advantageous concept for the versatile equipment of miniaturized devices with biologically active proteins. It comes along with new opportunities for immobilizing multiple functionalities on TMV adapter coatings, as desired, e.g., in handheld systems for point-of-care detection.

Carboxymethyl-Dextran-Coated Superparamagnetic Iron Oxide Nanoparticles for Drug Delivery: Influence of the Coating Thickness on the Particle Properties.

Carboxymethyl-dextran (CMD)-coated iron oxide nanoparticles (IONs) are of great interest in nanomedicine, especially for applications in drug delivery. To develop a magnetically controlled drug delivery system, many factors must be considered, including the composition, surface properties, size and agglomeration, magnetization, cytocompatibility, and drug activity. This study reveals how the CMD coating thickness can influence these particle properties. ION@CMD are synthesized by co-precipitation. A higher quantity of CMD leads to a thicker coating and a reduced superparamagnetic core size with decreasing magnetization. Above 12.5−25.0 g L−1 of CMD, the particles are colloidally stable. All the particles show hydrodynamic diameters < 100 nm and a good cell viability in contact with smooth muscle cells, fulfilling two of the most critical characteristics of drug delivery systems. New insights into the significant impact of agglomeration on the magnetophoretic behavior are shown. Remarkable drug loadings (62%) with the antimicrobial peptide lasioglossin and an excellent efficiency (82.3%) were obtained by covalent coupling with the EDC/NHS (N-ethyl-N′-(3-(dimethylamino)propyl)carbodiimide/N-hydroxysuccinimide) method in comparison with the adsorption method (24% drug loading, 28% efficiency). The systems showed high antimicrobial activity with a minimal inhibitory concentration of 1.13 µM (adsorption) and 1.70 µM (covalent). This system successfully combines an antimicrobial peptide with a magnetically controllable drug carrier.

Effect of composition and coordination number on some fundamental parameters in the Ge-Se glass

Chalcogenide glasses of GexSe100-x (x=10, 15, 20, 25 and 30 at.%) glasses were prepared by vacuum melting. An empirical relation between the glass transition temperature (Tg) and &lt;r&gt; is proposed by applying the Gibbs-Di Marzio equation for the Tg of a crosslinked polymer as a function of cross-linked density. We found a good agreement with the experimental result of Tg for GexSe100-x glasses. Several parameters such as mean atomic volume density, compactness, and free volume percentage which are more sensitive to the structure network changes were calculated. Their variation is discussed in connection with the proposed structural model. The variation of the molar volume and Tg with &lt;r&gt; indicates the coexistence of topological and chemical ordering effects. With the structural modification, the number of lone-pair decreases, and the covalent coupling of the structural network increases with increasing Ge content, due to the increases in the crosslinked between Ge and Se bridge.

Electronic structure modulation of Ru/W20O58 catalyst via interfacial Ru–O–W bridging bond for high-performance Li–O2 batteries

The development of advanced catalysts with high activity is crucial to addressing the issues of sluggish reaction kinetics at the cathode of Li–O2 batteries. Herein, the authors propose a facile strategy to synthesize Ru nanoparticles anchored on non-stoichiometric tungsten oxide nanosheets (Ru/W20O58) hybrids. The non-stoichiometric lattice structure of W20O58 provides abundant surface nucleation sites, and the defects-induced restriction effect inhibits the agglomeration of Ru nanoparticles. The interfacial covalent coupling between Ru and W20O58 facilitates charge transfer at the interface via Ru–O–W bridging bond and optimizes the electronic structure of catalysts surface. As the obtained Ru/W20O58 employed as cathode catalysts, Li–O2 batteries exhibit high specific discharge capacity of 6346.4 mAh g−1, improved rate performance and a cycling life of 260 cycles. The density functional theory calculation demonstrate that the interfacial coupling enhances the adsorption energy of intermediates on the surface and regulates the discharge reaction pathway, leading to the restraint of O2– nucleophilic attack and the formation of amorphous and decomposable discharge products. This work provides an insight on the correlation between electrochemical activity and interfacial coupling, shedding lights on a promising cathode catalyst for advanced Li–O2 batteries.

The Use of Mannose-Grafted and Lipopetide-Conjugated PE Liposomes in the Delivery of Docetaxel for the Treatment of Glioblastoma Multiforme: A Research Protocol

Introduction: One of the biggest obstacles in delivering anti-cancer drugs to brain tumours is the penetration of the blood-brain barrier. Docetaxel is a promising drug used for glioblastoma multiforme that works by promoting mitotic arrest and cell death of tumorous cells, yet it encounters this obstacle presented by the selectivity of the blood-brain barrier. Due to the barrier’s highly selective nature and the imprecision of current cancer treatments, the use of nanoparticles in drug delivery has been an area of significant interest. To address these issues, we propose using mannose and lipopeptide-grafted phosphatidylethanolamine liposomes as a drug delivery mechanism to effectively eliminate the obstacle of penetrating the blood-brain barrier in the treatment of glioblastomas. The truncated fibroblast growth factor and GALA lipopeptides increase the precision of the chemotherapeutic agent in targeting the tumour cells. Simultaneously, the mannose allows the nanoparticle to be recognized by sugar receptors on the blood-brain barrier, enabling it to pass through. This novel drug delivery system broadens the variety and increases the effectiveness of anti-tumoral drugs used in the treatment of brain cancer. Methods: The lipopeptides are prepared through pyridyl disulfide reactions. The phosphatidylethanolamine liposomes are prepared using standard thin-film hydration in which the lipopeptides, docetaxel, and calcein (to track the drug delivery) are incorporated into the liposomal lumen. Mannose is then grafted onto the liposomal surfaces through the covalent coupling of p-aminophenyl-D-glycosides to phosphatidylethanolamine liposomes. The synthesized liposomes would be administered intravenously alongside radiation. Statistical analyses will be conducted to measure the growth of the tumour and the accuracy of drug delivery. Discussion: The tumour cells should display a greater level of fluorescence, indicating a more accurate administration of the drug. It is expected that the patients will respond favourably to the treatment with the tumorous tissues showing a reduced growth rate and greater bioavailability of the drug. Conclusion: The liposomal drug delivery mechanism presents a novel method by which anti-tumoral drugs can both cross the blood-brain barrier and precisely target the tumorous mass, thereby reducing the risk of drugs getting lost within the vasculature and expanding the horizons for brain tumour prognoses.

Covalent coupling promoting charge transport of CdSeTe/UiO-66 for boosting photocatalytic CO2 reduction

Quantum dots (QDs) based heterojunction is a candidate for the photocatalytic CO2 reduction, owing to the large extinction coefficient and easy modification of band structures. However, the van der Waals interaction causes the large charge resistance and strong recombination centers between QDs and host materials, which makes the poor photocatalytic performance. Herein, a covalent bonded CdSeTe QDs and NH2-UiO-66 heterojunction (NUC-x) is constructed through an acylamino (-CONH-). The results indicate that the acylamino between NH2-UiO-66 and CdSeTe QDs can serve as the transfer channels for the photogenerated charges and stabilize the QDs. The optimized NUC-1200 achieved a CO generation rate of 228.68 µmol/g, which is 13 and 4 times higher than that of NH2-UiO-66 and CdSeTe QDs, respectively. This work provides a new avenue for efficient and stable photocatalysis of QDs.