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In this study, a pH-responsive magnetic drug delivery system was prepared by cross-linking of Cofe2O4/graphene oxide to carboxymethyl cellulose (CMC) biopolymer with adipic acid dihydrazide (ADH) and then investigated for loading and release of a poorly water-soluble anti-cancer drug, curcumin (CUR). The CoFe2O4/GO-ADH-CMC bio-nanocomposite was characterized by FE–SEM/EDX, TEM, FT–IR, XRD, TGA, VSM, and zeta-potential techniques. The highest amount of drug loading was achieved as 23.7 mg g–1 at 323 K, pH 6.0, and 120 mg L–1 CUR concentration. The study of adsorption isotherms revealed that the Sips model was best fitted to the equilibrium data (R2 > 0.997 and RMSE < 0.48), which indicated the contribution of both chemisorption and physisorption in drug loading. Furthermore, the release profile of CUR from drug-loaded CoFe2O4/GO-ADH-CMC was studied in mimicking the endosomal (pH = 5.6) and physiological (pH = 7.4) conditions. After 24 h, the maximum cumulative releases were found to be 86 and 38% at pH = 5.6 and 7.4, respectively. Also, the Peppas-Sahlin kinetic model was followed for the release data. The MTT assay exhibited good biocompatibility of the CoFe2O4/GO-ADH-CMC. The results implied that CoFe2O4/GO-ADH-CMC magnetic bio-nanocomposite might be utilized as a potentially safe carrier with the continuous and slow release of CUR.

The aim of this study was to replace cocoa butter substitute (CBS) with structured sunflower oil in chocolate spread partially. Two types of oleogel, 6% carnauba wax (CWO) and 2% carnauba wax with 4% adipic acid (AD—CWO) were substituted (at 20%, 50%, and 70%), and chocolate spread characteristics were evaluated. Various properties of chocolate spread samples were investigated as peroxide value, firmness, oil binding capacity, moisture content, molecular interactions, and molecular conformation of fat crystals. The increasement of CBS substitution by oleogel in samples significantly reduced firmness. The samples with 20% replacement formulated by CWO and AD-CWO had the highest oil binding capacity, 97.48 ± 0.21% and 97.73 ± 0.02, respectively. Moreover, oxidative stability analysis showed a positive correlation with an increasing replacement level over 90 days of storage. Based on FT-IR analysis, the new intermolecular hydrogen bond formation in the oleogel-based spreads network has been confirmed. CBS replacement with oleogels revealed the presence of stable β´ polymorphs with low intensity. In conclusion, the carnauba-based oleogels have significant potential to substitute CBS in chocolate spread partially.

Herein, an alternative method for adipic acid (AA) synthesis of industrial importance has been reported. The proposed novel method involves the one-step, solvent-free oxidation of a cyclohexane/cyclohexanone (CH/CH=O) mixture, with a cheap oxidizing agent such as O2 or air under mild conditions in the presence of N-hydroxyphtalimide (NHPI) and transition metals as catalysts. It has been showed that CH/CH=O mixture under applied mild conditions oxidized faster than CH and CH=O separately. This was due to the greater oxidizability of CH=O compared to CH. The peroxyl radicals formed by CH=O oxidation initiated the oxidation of the less reactive CH. Additionally, CH=O increased the polarity of the reaction mixture, promoting the solubility of NHPI. The influence of type and amount of catalyst, cyclohexane to cyclohexanone ratio, temperature, time, type of oxidizing agent on the composition of CH/CH=O oxidation products have been reported.

The liquid-phase hydrogenation of muconic acid (MA) to produce bio-adipic acid (AdA) is a prominent environmentally friendly chemical process, that can be achieved through two distinct methodologies: catalytic direct hydrogenation using molecular hydrogen (H2), or catalytic transfer hydrogenation utilizing a hydrogen donor. In this study, both approaches were explored, with formic acid (FA) selected as the hydrogen source for the latter method. Palladium-based catalysts were chosen for these processes. Metal’s nanoparticles (NPs) were supported on high-temperature heat-treated carbon nanofibers (HHT-CNFs) due to their known ability to enhance the stability of this metal catalyst. To assess the impact of support functionalization on catalyst stability, the HHT-CNFs were further functionalized with phosphorus and oxygen to obtain HHT-P and HHT-O, respectively. In the hydrogenation reaction, catalysts supported on functionalized supports exhibited higher catalytic activity and stability compared to Pd/HHT, reaching an AdA yield of about 80% in less than 2 h in batch reactor. The hydrogen-transfer process also yielded promising results, particularly with the 1%Pd/HHT-P catalyst. This work highlights the efficacy of support functionalization in improving catalyst performance, particularly when formic acid is used as a safer and more cost-effective hydrogen donor in the hydrogen-transfer process.

Background Paclitaxel (PAC) was the first-ever natural chemotherapeutic agent for the treatment of breast cancer. However, it has some drawbacks like low water solubility, a long half-life, an unregulated rate of discharge, etc. Thus, this research paper aimed to develop PAC-loaded nanoparticles to lessen toxicity and boost PAC's solubility in water. In this case, hyaluronic acid (HA), graphene quantum dots (GQDs), and adipic acid dihydrazide (ADH) have been combined in a unique way to suggest pH-responsive nanoconjugates that can improve the therapeutic effect of medicinal molecule PAC with fluorescence and breast cancer targeting. Results The investigation of the particle dimensions revealed that the majority of the particles were discovered to be between 25–50 nm. Additionally, the loading efficiency of PAC in PAC@HA-ADH-GQDs nanoconjugates was 93.56% and the release of PAC was around 70% at pH 5 and 20% at pH 7.4 in 24 h. The MTT test's risk-free methodology successfully supports the classification of HA-ADH-GQD as a biocompatible substance as it demonstrates cell viability of more than 75%. Additionally, cellular uptake research has shown that MCF7 cancer cells absorbed more PAC@HA-ADH-GQDs than GQDs alone due to the presence of targeting agent HA. Conclusion In this study, we have investigated the potential of the hyaluronic acid motif (HA-ADH-GQDs)-attached nanotherapeutics (NTCs) as a carrier for simultaneous fluorescence imaging and pH-triggered targeted administration of anticancer medication for the treatment of breast cancer. The suggested study is innovative since anticancer drug delivery using HA-GQDs NTCs with adhesive capabilities of ADH has not been previously described. Graphical Abstract Diagrammatic representation of the preparation of PAC@HA-ADH-GQDs NTCs for breast cancer targeting

Postoperative adhesions are common and severe complications, which affect up to 90 % of patients undergoing abdominal surgery. Despite the application of various strategies to minimize adhesions, the clinical outcomes remain far from satisfactory. Herein, we engineered a ROS-responsive and scavenging double-network hydrogel (PD-OHN) with multiple biofunctions and good mechanical properties for effective PAA prevention. First, a novel ROS-cleavable dithiothreitol (DTT) crosslinking monomer (DPBA) was synthesized. Subsequently, PD-OHN hydrogel was fabricated within 5 s by forming phenylborate ester bond networks between DPBA and polyvinyl alcohol (PVA), and acylhydrazone bond networks between oxidized hyaluronic acid (OHA) and adipic acid dihydrazide-modified hyaluronic acid (HA-ADH). After spraying, it can form a uniform and stretchable hydrogel film. Results showed that PD-OHN had good mechanical properties with a storage modulus about 20 kPa, satisfactory tissue adhesion strength of approximately 8 kPa, and an appropriate in vivo cecum retention time of about 21 days with good biosafety. More importantly, DPBA in PD-OHN hydrogel scavenged ROS via phenylboronate bond cleavage and the subsequent release of DTT, which intelligently alleviated oxidative stress according to the ROS levels in wound sites and induced pro-inflammatory M1 macrophages to polarize into anti-inflammatory M2 phenotype to alleviate inflammation. Further, the fibrinolytic system balance was recovered and fibrosis was reduced. Consequently, PD-OHN hydrogel effectively prevented adhesion formation in a cecum-sidewall abrasion rat model, and provided a promising whole course care anti-adhesion barrier for effective PAA prevention. [Display omitted] •A novel ROS-cleavable dithiothreitol prodrug crosslinking monomer was designed.•A double-network hydrogel PD-OHN was developed as bioactive anti-adhesion barrier.•PD-OHN has good mechanical properties, suitable tissue adhesion and cecum retention.•PD-OHN can intelligently scavenge ROS and polarize M1 macrophages to M2 phenotype.•PD-OHN effectively prevents adhesions via physical barriers and drug regulation.

•Pneumococcal polysaccharide type, 3 Ps3 was conjugated with diphtheria/tetanus toxoid.•ADH linker - Ps3 ratio was optimized to ensure Ps3 preservation and better coupling.•Protective epitopes in Ps3 and toxoids controlled by competitive and sandwich ELISAs.•Immunochemical activity data correlated with glycoconjugates immunogenicity in mice.•Using correlation model developed for Ps3-DTd, immunogenicity Ps3-TTd were predicted. A panel of derivatives were prepared from Streptococcus pneumoniae polysaccharide type 3 (Ps3) modified with adipic acid dihydrazide (ADH). The degree of coupling between Ps3-adh derivatives and diphtheria (DTd) or tetanus (TTd) toxoids was varied by ADH linker loading. A series of Ps3 derivatives and the resultant glycoconjugates (GC) were tested for their immunochemical activity in an ELISA. Antigenic properties of components in GCs were estimated by interaction with serotype-specific and toxin-neutralizing antibodies to confirm the preservation of native protective epitopes both of Ps3 and DTd. After immunization of mice, a correlation was established between immunochemical activity and immunogenicity of these GCs. A correlation model developed for Ps3-DTd conjugates allowed to predict the immunogenicity of similar design Ps3-TTd conjugates based on ELISA testing data. The plausibility of this prediction was confirmed by the test immunization of mice with Ps3-TTds. The proposed immunochemical approach to the assessment and control of native structural and functional antigenic elements in GCs is important for the optimization of vaccine design and is an adequate alternative to extensive physicochemical characterization for assessing immunogenicity.

The linear C 6 dicarboxylic acid adipic acid is an important bulk chemical in the petrochemical industry as precursor of the polymer nylon-6,6-polyamide. In recent years, efforts were made towards the biotechnological production of adipate from renewable carbon sources using microbial cells. One strategy is to produce adipate via a reversed β-oxidation pathway. Hitherto, the adipate titers were very low due to limiting enzyme activities for this pathway. In most cases, the CoA intermediates are non-natural substrates for the tested enzymes and were therefore barely converted. We here tested heterologous enzymes in Escherichia coli to overcome these limitations and to improve the production of adipate via a reverse β-oxidation pathway. We tested in vitro selected enzymes for the efficient reduction of the enoyl-CoA and in the final reaction for the thioester cleavage. The genes encoding the enzymes which showed in vitro the highest activity were then used to construct an expression plasmid for a synthetic adipate pathway. Expression of paaJ , paaH , paaF , dcaA , and tesB in E. coli BL21(DE3) resulted in the production of up to 36 mg/L of adipate after 30 h of cultivation. Beside the activities of the pathway enzymes, the availability of metabolic precursors may limit the synthesis of adipate, providing another key target for further strain engineering towards high-yield production of adipate with E. coli .

Mini review summarizes the emerging trends for the synthesis of adipic acid (AA) from metal nano catalysts which is a favourable catalysts for the title reaction. Countless steps are involved with catalysts will reduce the production of by-products and effluents produced in the traditional process. “Catalysis is intended for the protection of environment and quality of life”. Innumerable catalysts have been established Co 3 O 4 , Co/SiO 2 , Co/TiO 2 , Co-ZSM-5, MCM-Ti, TS-1, Co-ZSM, CoAlPO-11, Fe AlPO11/3, CoSiO 2 , Co/MgO. The catalysts crops of 1.3–6 % yield with a 98.7 % selectivity. Through the discovery and the vast applications of nanotechnology, a protocol from catalytic community to develop new CNT catalysts for adipic acid synthesis which is one of the most important commercial available aliphatic dicarboxylic acids, it has enormous industrial application in the manufacture of nylon-6, nylon-66. The reaction conditions, parameter, metal loading, ratio of metal, pressure will display key role in determining a selective catalysts for adipic acid synthesis. In the age of nano science CNT catalysts will play a role in replacing old traditional catalysts which will bring a new change in catalytic science defined as “Age of Nano- Science/Nano-Catalysis”. It is already renovating the science for the synthesis of AA with Nano-Catalysts i.e. CNT with metals. Through the expected impact brought by nanotechnology on new material, new characteristics and new devices, new applications for the synthesis of adipic acid is required to avoid pollution in main conventional process and established precision measurement technologies, the top priority task for the technically advanced countries is to convert the characteristic of nanotechnology into concrete economical effectiveness in practical application for the manufacture of AA and many more value added products which are useful in domestic purpose. Graphical Abstract

Coupling-onto approach was equipped to synthesis seven AB.sub.2-type miktoarm stars nanomaterials using carbodiimide chemistry. Glycine, the simplest amino acid is chosen as \"arm A\", seven biodegradable amides and polyamides as various \"arm B\" and amino adipic acid as \"core\" were used. The structures of these hydrophobic tridentate nano-stars were confirmed with FT-IR and .sup.1H NMR. The diameter of the nano-stars recorded via DLS ranged from 256.3 nm to 933.4 nm. TGA analysis of the product reported a noticeable loss of 32% by total mass at 400 °C, indicating thermal degradation. The products show significant structural degradation after 15 days of biological treatment with E. coli. All the seven tridentate nano-stars can potentially be equipped as drug-delivery vehicles.