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Operando DRIFT spectroscopy is used to elucidate the role of key reaction intermediates during toluene oxidation on a Pd/CeO2 catalyst and bare CeO2 support. Selective identification of active surface species and their discrimination from spectators were carried out by combining concentration-modulation excitation spectroscopy (c-MES) experiments with phase-sensitive detection (PSD) spectral analysis. The resolution of highly overlapped infrared bands in MES-PSD spectra was performed by a chemometric multivariate curve resolution-alternating least squares (MCR-ALS) method. Pd/CeO2 catalyst completely oxidizes toluene to CO2 (T50 = 235 oC), while pure CeO2 activates the toluene molecule but incomplete combustion to CO and formaldehyde is observed. Our results revealed that the methyl group of adsorbed toluene on the ceria surface is activated by subtraction of an H atom by a lattice O−2, forming benzyl (C6H5CH2-) species intermediate. Then, the benzyl species is stepwise oxidized to benzyl alcohol, benzaldehyde, and benzoate. Subsequent decarboxylation of benzoate and oxidation of the aromatic ring produces formate and aldehyde-like species, which are finally oxidized to CO2 and water. Alternatively, the benzoate intermediate can be oxidized to anhydride species (maleic anhydride or succinic anhydride) that accumulates on the surface and are slowly oxidized to CO2. The main role of the palladium metal nanoparticles is to facilitate the replenishing of the lattice oxygen via a metal-assisted Mars-van Krevelen mechanism. These findings provide molecular insights into a key environmental catalysis process, which will improve the rational design of optimized catalytic systems.

The moisture resistance of friction-welded wood joints can be improved by applying bio-based bonding additives. Several biomolecules including tannic acid, organosolv lignin from hardwood, kraft lignin from softwood, and derivates thereof, were investigated regarding their applicability as bonding additives in the friction welding process. Welding with kraft lignin showed significantly increased moisture stability after 24 h water immersion. An average wet bond strength of 1.5 MPa compared to 0.38 MPa of untreated spruce was obtained. Modification of kraft lignin through succinylation, acetylation or depolymerisation led to no further improvement in moisture stability. Depolymerised kraft lignin resulted in an even higher delamination rate of the samples during water immersion than untreated samples. Structural analysis of the lignin variations by FTIR-ATR, GPC and P-31 NMR in combination with thermal analysis by TGA and DSC showed the impact of various structural and chemical features on the thermal behaviour and intermolecular interactions of the applied lignin., Journal of Adhesion Science and Technology, ISSN:0169-4243, ISSN:1568-5616

Compared with the traditional suspension fermentation, immobilised biofilm fermentation has advantages of strong resistance, high yield and continuous fermentation and is conducive to improving the industrial fermentation methods. The formation of a biofilm on correct supports is critical to immobilised fermentation. In this study, Pichia pastoris was used to understand and control the modification of surface properties of supports and cells. Following deletion of gene PAS_chr2-1_0773, in P. pastoris △0773, the cell-surface negative charge density decreased and hydrophobicity improved, which was conducive to adhesion. Therefore, according to the changing trend of cell surface properties, cotton fibre was used with succinic anhydride (SA) to modify the carrier for changing the surface properties for efficient conduction of immobilised fermentation. In the fermentation process, the adhesion between the modified cotton fibre and yeast was better than that between an unmodified cotton fibre and yeast, and the additive amount increased by ∼25 %. The enzyme activity of the △0773-cotton-SA fermentation system reached 302.7 U/mL, which was 39.6 % higher than that of the original fermentation system. Therefore, this study provides a guide for significant improvement of immobilised fermentation of fungi.

Nonenyl succinic anhydride (NSA) modification could be an alternative to octenyl succinic anhydride (OSA) modification of starch to obtain a range of physicochemical and rheological properties and for emulsification applications. In this work, a series of NSA-modified quinoa starches in granular form with different degrees of substitution (DS) (0.0080, 0.0175, 0.0359, and 0.0548) were prepared. The NSA modifications reduced the gelatinization temperatures and frequency dependence of storage modulus (G'), while increasing the peak viscosity, gel hardness, and G'. The NSA-modified quinoa starches with medium DS were the most effective in stabilising Pickering emulsions. The droplet size of Pickering emulsions decreased first with increasing DS before increasing at the highest DS. Modified starch with DS of 0.0359 had the highest emulsifying capacity. Apart from the commonly used octenyl succinic anhydride (OSA) modification, the NSA modification of starches could be a potential candidate as efficient Pickering emulsion stabilizers.

BACKGROUND Curcumin has become increasingly popular in functional foods and beverages field as a result of its high biological activity. Nevertheless, the application of curcumin is usually limited by its poor water solubility, low absorption, rapid metabolism and instability. Accordingly, the development of an appropriate wall material is crucial for its effective use. In the present study, curcumin-octenyl succinic anhydride modified pullulan (Cur-OSAP) micelles were successfully prepared by an anti-solvent co-precipitation method. RESULTS Octenyl succinic anhydride modified pullulan (OSAP) micelles exhibited the highest encapsulation efficiency (57.31%) and loading capacity (5.73%) of curcumin when the mass ratio of OSAP to curcumin was 10:1 and the degree of substitution of OSAP was 0.0469, at which point Cur-OSAP micelles formed via hydrogen binding and hydrophobic interactions, as confirmed by Fourier transform infrared and fluorescence techniques. The transmission electron microscopy results showed that the Cur-OSAP micelles were roughly spherical in shape with diameters in the approximate range 30-60 nm. CONCLUSION The encapsulation of OSAP greatly improved photostability and sustained release properties of curcumin in Cur-OSAP micelles. These findings suggest that OSAP can be used as a carrier to encapsulate and protect hydrophobic food ingredients. © 2021 Society of Chemical Industry.

The aim of this study was to investigate the effect of impregnating materials (low molecular weight phenol formaldehyde or LmwPF and succinic anhydride or SA), their concentrations (5and 10%), and compression ratios (20 and 40% from initial thickness)on improvement of specific gravity (SG) and dimensional stability on nyatoh, sepetir, and pisang putih wood; and then compared them to control and densified wood. The results showed that SG and dimensional stability of compregnated wood were affected by all parameters studied. Higher compression ratio and concentration will result in a greater improvement.In general, SG and dimensional stability of compregnated wood were better than the control.SG of LmwPF-and SA-compregnated wood increased by 10.69‒22.31% and 6.96‒23.09%, respectively. Utilization of LmwPF and SA has significantly reduced the spring-back, butthe latter is better. Thecompression-set recovery after compregnation was 18.34‒33.99%, while after densification was 47.86‒71.49%.

Carrier-free drug self-delivery systems consisting of amphiphilic drug-drug conjugate (ADDC) with well-defined structure and nanoscale features have drawn much attention in tumor drug delivery. Herein, we report a simple and effective strategy to prepare ADDC using derivatives of cisplatin (CP) and dasatinib (DAS), which further self-assembled to form reduction-responsive nanoparticles (CP-DDA NPs). DAS was modified with succinic anhydride and then connected with CP derivative by ester bonds. The size, micromorphology and in vitro drug release of CP-DDA NPs were characterized. The biocompatibility and bioactivity of these carrier-free nanoparticles were then investigated by HepG2 cells and H22-tumor bearing mice. In vitro and in vivo experiments proved that CP-DDA NPs had excellent anti-tumor activity and significantly reduced toxicities. This study provides a new strategy to design the carrier-free nanomedicine composed of CP and DAS for synergistic tumor treatment., Graphical abstract A carrier-free, reduction-sensitive nanoparticle based on cisplatin and dasatinib for synergistic antitumor Image, graphical abstract

Phenol is the toxicant present in cigarette smoke that causes pulmonary diseases, eyes infection, and even various kinds of cancer. So, in this research, an attempt was done to prepare a suitable absorbent to remove phenol from cigarette smoke. A novel bio-based adsorbent succinylated carboxymethyl starch (S-CMS) was prepared by reacting carboxymethyl starch (CMS) with succinic anhydride (SA) in the presenting of N, N-dimethylformamide (DMF) solvent and pyridine. The structure of the S-CMS was confirmed by spectroscopic techniques including proton nuclear magnetic resonance and Fourier transform infrared. The S-CMS crystallinity and thermal properties were checked by x-ray diffraction and thermogravimetric analysis. The results showed a decrease in thermal properties and crystallinity for S-CMS. The S-CMS were tested as adsorbents for the removal of phenol. The adsorption efficiencies of CMS, S-CMS1, S-CMS2, and S-CMS3 towards phenol were shown to be 0.297 g/g, 0.321 g/g, 0.322 g/g, and 0.324 g/g, respectively.

The purpose of this study was to investigate the delivery of poorly water-soluble non-steroidal anti-inflammatory drugs (NSAIDs) by carboxyl-functionalized mesoporous silica nanoparticles (MSN-COOH) with high specific surface area (SBET). In this study, MSN-COOH was prepared by collaborative self-assembly using cetyltrimethylammonium bromide (CTAB) as template and hydrolysis (3-triethoxyl-propyl) succinic anhydride (TESPSA) as co-structure auxiliary directing agent (CSDA). The drug delivery systems were constructed with NSAIDs including Nimesulide (NMS) and Indomethacin (IMC) as model drugs. Moreover, the characterization techniques, hemolysis and bio-adsorption testes, in vitro drug release and in vivo biological studies of MSN-COOH were also carried out. The characterization results showed that MSN-COOH is spheres with clearly visible irregular honeycomb nanopores and rough surface (SBET: 1257 m2/g, pore volume (VP): 1.17 cm3/g). After loading NMS/IMC into MSN-COOH with high drug loading efficiency (NMS: 98.7 and IMC: 98.2%), most crystalline NMS and IMC converted to amorphous phase confirmed using differential scanning calorimeter (DSC) and X-ray power diffraction (XRD) analysis. Meanwhile, MSN-COOH significantly increased the dissolution of NMS and IMC compared with non-functionalized mesoporous silica nanoparticles (MSN), which was also confirmed by wettability experiments. The results of in vivo biological effects showed that MSN-COOH had higher bioavailability of NMS and IMC than MSN, and exerted strong anti-inflammatory effects by delivering more NMS and IMC in vivo. Statement of significance This study successfully prepared MSNs-COOH (mesoporous silica nanoparticles modified with negatively charged carboxyl groups on the surface and in the pores) with high specific surface area and pore volume by using the negatively charged carboxyl group (hyd-TESPSA) and the positively charged CTAB self-assembled through electrostatic attraction under alkaline conditions. The drug delivery systems were constructed with Nimesulide (NMS) and Indomethacin (IMC) as model drugs. The results showed MSNs-COOH had high drug loading capacity and also exhibited good in vitro drug release properties. Interestingly, NMS loaded MSNs-COOH also had a potential pH responsive release effect. In vivo biological studies revealed that NMS/IMC loaded MSNs-COOH could evidently improve the bioavailability and played the strong anti-inflammatory effects.

Hydrophilic polyethylene glycol monomethyl ether (mPEG) was grafted onto Icariin (ICA) by succinic anhydride to form a polyethylene glycol-Icariin (mPEG-ICA) polymer. The structure of the polymer was characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). mPEG-ICA nanoparticles loaded with ICA were prepared by physical embedding of ICA by dialysis. The particle size was determined to be (220 ± 13.7) nm, and the ζ potential was (2.30 ± 1.33) mV by dynamic light scattering (DLS). Under a transmission electron microscope (TEM), the nanoparticles were spherical, and the morphology was regular. In the medium with pH 7.4, the drug release rate of mPEG-ICA nanoparticles reached (52.80 ± 1.70)% within 72 h. At pH 6.8, the cumulative drug release of nanoparticles reached (75.66 ± 0.17)% within 48 h. Treatment of the nanoparticles with LPS-treated H9c2 cells maintained cell viability, reduced LDH release and exerted antiapoptotic effects. Moreover, ICA-loaded mPEG-ICA nanoparticles significantly decreased the mRNA expression of the myocardial inflammatory cytokines TNF-α, IL-1β and IL-6M. In conclusion, ICA-loaded mPEG-ICA nanoparticles protected against LPS-induced H9c2 cell injury.

Recently, food industries are directing on the promotion of innovative food matrices fortified with bioactive compounds in order to enhance the consumer's health. Octenyl succinic anhydride modified starches (OSA-MS) such as Hi-cap100 (HCP) and purity gum 2000 (PUG) were used to fabricate emulsions co-entrapped with borage seed oil (BSO), resveratrol (RES) and curcumin (CUR), which were further spray dried to obtain powders. The fabricated microcapsules loaded with BSO, RES, and CUR displayed excellent dissolution performance, high encapsulation efficiency (≈93.05%) as well as semi-spherical shape, revealed via scanning electron microscopy (SEM). We also evaluated the impact of storage time (4 weeks) and temperature (40 °C) on the physicochemical characterization of OSA-MS coated microcapsules. Microcapsules coated with HCP exhibited greater oxidative stability, lower water activity and moisture contents rather than PUG coated microcapsules during storage because of its good film-forming properties. Addition of CUR enhanced the oxidative stability and retention of bioactive compounds. HCP microcapsules loaded with BSO + RES + CUR presented supreme retention of RES (70.32%), CUR 81.6% and γ-linolenic acid (≈ 96%). Our findings showed that CUR acted as an antioxidant agent; also, lower molecular weight OSA-MS as wall material could be used for the entrapment of bioactive compounds and promotion of innovative food products.

Polyoxometalates (POMs), large oxoanions of the group 5 and 6 elements, attract attention due to their use as oxidation-stable catalysts and ligands. Different from the well-known V, Mo, and W POMs, the group V POMs of Ta assemble and are stable only in highly alkaline solution rather than acidic solution. In this paper, we successfully synthesized and structurally characterized two unprecedented peroxotantalum-containing clusters, KNa2[HSe2(TaO2)6(OH)4(H2O)2O13]·15H2O (1) and Cs2K1.5Na1.5[Se4(TaO2)6 (OH)3O18]·17H2O (2), which comprises a 6-peroxo-6-tantalum core stabilized by two and four selenite centers, respectively. The simple, one-pot synthesis of 1 and 2 involving addition of sodium selenite into the acidified hexatantalate aqueous solution in the presence of hydrogen peroxide could represent a general procedure for incorporating heteroatoms into peroxo-polyoxotantalate species, thus opening new possibilities for this emergent branch of polyoxotantalate chemistry. Moreover, the catalytic properties of these two compounds were investigated using succinic anhydride and phenylamine as the model substrate, and compound 2 presents excellent catalytic activity in the amidation reactions of anhydrides and amines.

The shortcomings arising from usage of native starches in various industrial processes have demanded the need for modification in order to enhance its functionality. This study investigated the impact of ethanol concentration on pasting, structural, morphological, and functional properties of succinylated potato starch. Some granules of the potato starch sample also appeared to be multilobed and fractured. The Fourier transform -1 infrared spectroscopy (FT-IR) study revealed the presence of carbonyl group (1747 cm-1 ) in the starch chains as an additional functional group after succinylation. The statistical analysis of the study data revealed a significant (p < 0.05) decrease in protein, fat, fibre, ash, and reduction in moisture contents after modification. Analysis with visco-analyzer showed reduction in pasting parameters after modification. Modification of native potato starch with ethanol improved the functionality of the starch by imparting some additional physicochemical and functional properties. These improved properties upon modification, therefore, suggest some potential favorable qualities for special applications.

This study including synthesis of some new Schiff bases compounds [1‐6] from the reaction of Sulfamethoxazole drug with some aromatic aldehydes in classical Schiff base method then treatment Schiff bases with succinic anhydride to get oxazepines rings [7-11]These derivatives were characterized by melting point, FT‐IR, 1H NMR and mass spectra. Some of synthesized compounds were evaluated in vitro for their antibacterial activities against three kinds of pathogenic strains Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa by agar diffusion disk method, and against the fungal species (Candida). The results showed that some of these derivatives have good antibacterial activities compared to biological activity of parent drug.

In this work, surfactant-modified starches were prepared by reactive extrusion (REX) and used as stabilizers for olive oil-in-water Pickering emulsions. The referred starches are waxy maize starch phosphate (P-MS), octenyl succinic anhydride maize starch (OSA-MS), and octenyl succinic anhydride rice starch (OSA-RS). Pickering emulsions were emulsified by microfluidization and spray-dried to evaluate the efficiency of encapsulation and the protective effect of starch derivatives in the encapsulated olive oil. Results showed that OSA-RS presented the smallest particle size and the most electronegative $$\zeta$$ -potential. Among the considered starches, OSA-RS possesses the best characteristics as surfactant to improve emulsification and digestibility of oil-in-water Pickering emulsions. On the other hand, P-MS has the ideal properties to be used as wall material for spray drying to increase oil stability and reduce digestibility of microcapsules.

The development of C(sp(3))−H functionalizations of free carboxylic acids has provided a wide range of C−C and C−Y (Y = heteroatom) bond-forming reactions that both complement and expand upon what can be achieved through conventional methods. Additionally, C−H functionalizations have lent themselves to the one-step preparation of a number of valuable, synthetic motifs, that are often difficult to prepare through conventional methods. Herein, we report a β- or γ-C(sp(3))−H carbonylation of free carboxylic acids using Mo(CO)(6) as a convenient solid CO source and enabled by a bidentate ligand, leading to convenient syntheses of cyclic anhydrides. Among these, the succinic anhydride products are versatile stepping stones for the mono-selective introduction of alkyl, alkenyl, aryl, alkynyl, boryl, silyl, fluoro, iodo, and thiophenyl groups at the β position of the parent acids by decarboxylative functionalizations, thus providing a divergent strategy to synthesize a myriad of carboxylic acids inaccessible by previous β-C−H activation reactions. The enantioselective carbonylation of free cyclopropanecarboxylic acids has also been achieved using a chiral bidentate thioether ligand.

Heating bleached kraft pulps treated with poly(ethylene-alt-maleic acid) (PEMAc) can lead to high yields of carboxylated polymer grafted to fibers. However, in many cases, the cured, dry pulp cannot be effectively repulped (redispersed in water) because the wet strength is too high. Impregnation with PEMAc solutions at pH 4 followed by high temperature (120-180 °C), catalyst-free curing for short times can give fixation yields >85% while maintaining repulpability. The combination of high fixation yields with low wet strength is possible because the extent of curing required for high grafting yields is less than the curing requirement for high wet strength. Two challenges in moving this technology to practicable applications are (1) identifying the optimum laboratory pulp curing conditions and (2) translating laboratory curing conditions to industrial processes. A modeling tool was developed to meet these challenges. The model is based on the observation that for curing conditions giving high fixation yields the wet tensile indices of grafted pulp sheets showed a power-law dependence on the βΓ product where β is the conversion of the succinic acid moieties in PEMAc to the corresponding succinic anhydride groups in the curing step and Γ is the amount of polymer applied to the pulp. For two PEMAc molecular weights and two pulp types, the power-law slopes were 0.6; however, the pre-exponential terms depended upon the specific polymer and pulp type combination. We propose that the relationships between the wet tensile index and βΓ, from polymer-treated, laboratory pulp handsheets, can be used to predict if proposed curing conditions for larger-scale processes will produce a repulpable product.

We investigated the effect of succinic anhydride (SA) addition on electrochemical behavior of magnesium (Mg) metal electrodes. A sufficient amount of SA addition suppressed the decomposition of the...

In this study, the effect of the deep eutectic solvent (DES) based on triethylmethylammonium chloride and imidazole on the mechanochemical succinylation of sawdust was investigated. The sawdust was ball milled in the presence of succinic anhydride and the effects of different amounts of the DES on the carboxylic acid content and particle size were studied with and without post-heating. The carboxylic acid content significantly increased with the addition of the DES and by using 1.5 mass excess of the DES compared to sawdust; milled sawdust with 3.5 mmol/g of carboxylic acid groups was obtained using 60 min post-heating at 100 °C. The particle size was found to depend strongly on DES-to-wood ratio and a change in size-reduction characteristics was observed related to fiber saturation point. After mechanochemical milling, three succinylated sawdust samples with different carboxylic acid contents were disintegrated into wood nanofibers and self-standing films were produced. Although the mechanical properties of the films were lower than the cellulose nanofibers, they were higher or in line with oil- and biobased polymers such as polypropene and polylactic acid, respectively. Because of their amphiphilic nature, wood nanofibers were found to be effective stabilizers of water–oil emulsions.

To prepare a robust biocatalyst and enhance the removal of bisphenol A in wastewater, succinic anhydride was reacted with laccase to obtain succinic anhydride-modified laccase (SA-laccase) and then co-crystallized with Cu3(PO4)2 to form SA-laccase@Cu3(PO4)2 hybrid nanoflowers (hNFs). The activity of SA-laccase@Cu3(PO4)2 reached 5.27 U/mg, 1.86-, 2.88- and 2.15-fold those of bare laccase@Cu3(PO4)2, laccase@Ca3(PO4)2 and laccase@epoxy resin, respectively. Compared with free laccase, the obtained hNFs present enhanced activity and tolerance to pH and high temperature in the removal of BPA. Under the optimum conditions of pH 6.0 and 35 °C, BPA removal reached 93.2% using SA-laccase@Cu3(PO4)2 hNFs, which was 1.21-fold of that using free laccase. In addition, the obtained SA-laccase@Cu3(PO4)2 hNFs retained nearly 90% of their initial catalytic activity for BPA removal after 8 consecutive batch cycles. This efficient method for preparing immobilized laccase can also be further developed and improved to acquire green biocatalysts for removing persistent organic pollutants in wastewater.

A novel cationic surfactant type of N'alkyl N,'N'dimethyl-4-morpholino-4-oxobutanoylhydrazinium iodide (10a–12a) and N'alkyl N', N'dimethyl-4-piperidino-4-oxobutanoylhydrazinium iodide (10b–12b) of quaternary hydrazinium moieties in hydrophilic parts was synthesized. These quaternary hydrazinium surfactants were obtained using a two-step reaction scheme, starting from ring opening of succinic anhydride with a base (morpholine, piperidine), followed by ammonolysis with hydrazine hydrate, then alkylation of the amino group with alkyl bromides (RBr) that have different hydrophobic chain lengths (R, C12H25, C14H29, and C16H37), and ending with the quaternarization of the secondary amino group by two moles of methyl iodide. The chemical composition of the surfactants was analyzed by FTIR, 1HNMR, mass spectroscopy, and elemental analysis. A variety of surface-active characteristics were achieved by surface calculations, including CMC, γcmc, CMC/C20, Γmax, pC20, Amin, and Πcmc. These surface characteristics and foam stability rely on the nature of the hydrophobic chain. Preliminary results showed that an upgrade throughout the CH2 group in the fatty chain and the morpholine or piperidine ring lowers the CMC and increases the foaming capacity and stability of the quaternary hydrazinium surfactants. Anionic dye (Acid BG) interactions with 12b surfactant (as an example) were studied using the spectrophotometric technique and the binding constant (170.64 dm3.mol−1) was determined. The results indicate solubilization and binding took place at a large scale. Furthermore, considerable biodegradation of cationic surfactants was observed (68–87%). The antimicrobial activity of these surfactants has also been observed with the minimum inhibitory concentration (MIC) and the size of inhibited growth zone. The smallest MICs were found in 12a (64 µg/mL) and 12b (32 µg/mL) surfactants, indicating the highest antimicrobial activity.

Curcumin (CUR) manifests anti-colon cancer activity but suffers from low solubility, bioavailability, and instability, rendering it not as effective as its chemotherapeutic cousins. Here, we conjugate CUR to succinic anhydride (SA), (CUR.SA conjugate), subsequently formulated in mannose-conjugated chitosan nanoparticles (CUR-NPs and CUR.SA-NPs). Instrumental analyses confirmed formation of CUR.SA and mannosylated chitosan (CM) conjugates, with CUR.SA being less crystalline thus, more soluble. Average particle size of CUR-NPs and CUR.SA-NPs were 268 ± 6 nm and 342 ± 4.6 nm, with drug entrapment of 93.34 ± 0.40 % and 98.46 ± 0.06 % respectively. In vitro releases of CUR and CUR.SA from nanoparticles in pH 1.2 and 6.8 media were slow and sustained over 2 h and 72 h, respectively. The physical characteristics of the nanoparticles were unchanged over 3 weeks of storage. Thus, a successful CUR.SA conjugate has been developed, couriered in CM nanoparticles, with favorable attributes that warrant further anti-colon cancer studies, which is ongoing. This work was supported by Qatar University Grant No IRCC-2021-006. Authors acknowledge the Central Laboratory Unit and Center of Advanced Materials, Qatar University for support in sample analyses.

Colon cancer (CRC) is the second leading cause of death and the third most diagnosed type worldwide. Although curcumin (CUR) has potent anticancer activity, it suffers from low solubility, bioavailability, and instability. This study aims to conjugate CUR to succinic anhydride (SA) and then formulate in mannosylated-chitosan nanoparticles (CUR.SA-NPs). The formulation was optimized in comparison to curcumin only in the same delivery system. Dynamic light scattering (DLS) studies disclosed a higher size of CUR-NPs (268 ± 6 nm) and CUR.SA-NPs (342 ± 4.6 nm) compared to empty delivery system, CM-NPs, (101 ± 4.3 nm). Conversely, the zeta-potential was reduced from 41.2 ± 0.15 mV to 11 ± 0.75 mV and 13.6 ± 0.8 mV for CUR-NPs and CUR.SA-NPs respectively. The entrapment efficiency was 93.34 ± 0.40 for CUR-NPs, and 98.46 ± 0.06 for CUR.SA-NPs. Physical and structural characteristics of the formulated nanoparticles were investigated using FTIR, NMR, XRD, SEM, and TGA and each attest to the formation of the functionalized CUR.SA-CMNPs. In vitro drug release illustrated a sustained release profile of CUR and CUR.SA over a period of 3 days and an excellent cytotoxicity and intracellular uptake by CRC cell lines (SW480 and HCT116). Thus, CUR-NPs and CUR.SA-NPs can be considered as a promising delivery strategy for CRC treatment.

This study examined the effects of different sequential treatments of dextran glycation and succinic anhydride acylation on the structure and physicochemical properties of soy protein isolate (SPI). The tested properties included electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy, endogenous fluorescence spectroscopy, surface hydrophobicity (H0 ), free sulfhydryl (-SH), solubility, interfacial properties, rheological properties, and scanning electron microscope (SEM). The results show that the two treatments significantly improved the structure and functional characteristics of the SPI. The order of the methods had an important effect on the SPI. The lowest H0 (231.76 ± 11.92), the highest free -SH content (3.09 ± 0.09 µmol/g), and the highest solubility at pH = 7 (77 ± 3.97%) were obtained when the acylation treatment was followed by the glycation treatment. Emulsification, emulsion stability, foaming, and foam stability were also the highest. Glycation and acylation caused the viscosity coefficient (k) of the SPI solution to decrease compared with SPI alone, but the flow index (n) value increased, and the sum G' value of the conjugate system decreased as gel time increased. SEM showed that its microstructure has changed significantly. Therefore, this research provided an effective method for improving the functional characteristics of SPI and had potential industrial application prospects. PRACTICAL APPLICATION: Glycation and acylation of soybean protein isolate improved the chemical modification method of protein, improved the functional properties of soybean protein, widened its application in food and materials, and provided a new idea for the further development and utilization of soybean protein.

Poly(ester-carbonate) copolymers were synthesized through triethylborane (TEB)-activated, one-pot copolymerization of epoxides with anhydrides (AH) and CO₂. Depending upon the feeding ratio of AH to the epoxides, poly(ester-carbonate) copolymers with random and tapered ester structures could be derived due to the much higher reactivity of AH toward growing oxanions compared to the reactivity of CO₂. Anhydrides like succinic anhydride (SA) and phthalic anhydride (PA) when tried in terpolymerization with epoxides, like propylene oxide (PO) and cyclohexene oxide (CHO), and CO₂ indeed exhibited such high reactivities in comparison to CO₂ that tapered block structures were eventually obtained for high feeding ratios of AH to PO and random copolymers for the AH-to-epoxide feeding ratio lower than 10%. Terpolymerization with different feeding ratios of anhydrides to epoxides was thus systematically investigated. In an alternate path, diblock poly(ester-b-carbonate)s were prepared by sequential copolymerization of epoxide/anhydride and epoxide/CO₂. All of the obtained copolymers were characterized by ¹H nuclear magnetic resonance (NMR), diffusion-ordered spectroscopy (DOSY), gel permeation chromatography (GPC), and differential scanning calorimetry (DSC). The structures and properties of copolymers obtained by terpolymerizations and block copolymerizations were compared.

Gang Gui,1,* Ziqi Fan,1,* Yihuan Ning,1 Cancan Yuan,2 Baolin Zhang,3 Qin Xu1 1College of Pharmacy, Guilin Medical University, Guilin, 541004, People’s Republic of China; 2Department of Pharmacy, Luohe City People’s Hospital, Luohe, 462000, People’s Republic of China; 3College of Materials Science and Engineering, Guilin University of Technology, Guilin, 541004, People’s Republic of China*These authors contributed equally to this workCorrespondence: Qin XuCollege of Pharmacy, Guilin Medical University, Guilin, 541004, People’s Republic of ChinaEmail xuqincpu@126.comBaolin ZhangCollege of Materials Science and Engineering, Guilin University of Technology, Guilin, 541004, People’s Republic of ChinaEmail zhangbaolin@glut.edu.cnBackground: Paclitaxel (PTX) has interesting anticancer activity. However, it is insoluble in water, which seriously hinders its use in clinical. Superparamagnetic iron oxide nanoparticles (SPIONs) are used as an ideal drug delivery system. Therefore, we proposed a folic acid (FA) targeting drug-loaded SPIONs to reduce its adverse reaction.Methods: To improve the hydrophilicity of PTX, the structure of PTX was modified by succinic anhydride to obtain 2ʹ-succinate paclitaxel (SPTX). FA conjugated Polyethylene glycol (PEG)/polyethyleneimine (PEI)-SPIONs SPTX-loaded nanoparticles (SPTX@FA@PEG/PEI-SPIONs) were prepared by solvent volatilization and hydrogen bond adsorption, and the nano-formulation was optimized by response surface methodology (RSM). The characteristics, antitumor effect in vitro, pharmacokinetics, and biodistribution of SPTX@FA@PEG/PEI-SPIONs were evaluated.Results: SPTX was successfully loaded on the surface of FA@PEG/PEI-SPIONs. The formation of SPTX@FA@PEG/PEI-SPIONs was exhibited water-dispersive monodispersity with high stability by RSM, and dynamic light scattering (DLS) was 178.1± 3.12 nm, particle size observed in the transmission electron microscope (TEM) was 13.01± 1.10 nm, and the encapsulation efficiency (EE) and loading efficiency (LE) were 81.1± 1.66% and 14.8± 1.46%, respectively. It enhanced the stability in normal physiological condition, accelerated drug release at tumorous pH, and preferentially prolonged the circulation time. In vitro, the SPTX@FA@PEG/PEI-SPIONs significantly targeted to folate receptor (FR) positive cancers cell (HNE-1) via the receptor-ligand mediated pathway, resulting in effective cytotoxic activity. Pharmacokinetic results demonstrated that SPTX@FA@PEG/PEI-SPIONs (t1/2=3.41 h) had longer than free SPTX or PTX (t1/2=1.67 h) in rats in vivo. Tissue distribution studies showed that SPTX@FA@PEG/PEI-SPIONs were present at high levels in the liver and help in targeting the folate receptors present on the kidneys.Conclusion: These results suggest that SPTX@FA@PEG/PEI-SPIONs offer a highly promising approach to control drug release, improve drug pharmacokinetics and actively target the nasopharyngeal carcinoma.Keywords: paclitaxel, folic acid, superparamagnetic iron oxide nanoparticles, targeted drug delivery, response surface methodology, anti-nasopharyngeal carcinoma

Succinylated starches (SS) were prepared by the reaction of normal starch (NS) and porous starch (PS) with succinic anhydride (SA) in the presence of DMF solvent and base pyridine, respectively. The proton nuclear magnetic resonance and Fourier transform infrared were used to confirm the successful synthesis of the SS (SS1, SS2, SS3 and SS4, respectively). The X-ray diffractometer XPert PRO (Cu Kα, λ = 1.54 A) was used to study the crystallinity of NS, PS and SS. The XRD analysis showed that the SS exhibited amorphous nature after succinylation. Thermogravimetric analysis and differential thermal analysis of NS, PS and SS showed that succinylation decreased the thermal stability. The morphology of the NS, PS and SS was studied by SEM. These SS were used as adsorbents for phenol removal. The adsorption efficiencies for phenol by NS, SS1, SS2, SS3 and SS4 were found to be 0.084 g/g, 0.165 g/g, 0.173 g/g, 0.183 g/g and 0.189 g/g, respectively.

In this study, Alkenyl succinimides with different alkyl chain lengths were synthesized using polyisobutylene (PIB) with the molecular weights of 1000 and 1300, which displayed the best functional properties. The secondary amines found in b-Polyisobutylene succinimide (b-PIBSI) dispersants were prepared by attaching PIB chains to a polyamine core via two succinimide moieties. In this work, detergent/dispersant type additives were synthesized based on polyisobutylene succinic anhydride (PIBSA) and its aminated compounds (PIBSI) with tetraethylenepentamine (TEPA). The resulting PIBSA and PIBSI characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and gel permeation chromatography (GPC) spectroscopies were greatly complicated because of the interactions between the carbonyls of the succinimide groups and unreacted secondary amines of the Mb-PIBSI dispersants. The viscoelasticity of obtained PIBSI indicated the increase in storage modulus with time which illustrated the increase in the solid-like properties of PIBSI. Therefore, an alternative procedure was developed based on fluorescence quenching of the succinimides by secondary amines and urethane groups.

Herein we report a route to sulfur–starch composites by the modification of corn starch with octenyl succinic anhydride (OSA, degree of substitution = 2.6%) and its subsequent reaction with elemental sulfur through an inverse vulcanization process to generate OSSx (where x = wt% sulfur, either 90 or 95). This work represents an expansion into a previously untapped biomass source for the preparation of recyclable thermoplastic materials by this process. Composites OSSx are comprized of 83–89% by mass of extractable sulfur, and have reasonable thermal stability (Td = 214–216 °C) and Tm (DSC) of 118 °C. The starch modification strategy employed herein allowed for lower degree of substitution of the starch than was feasible for other bioploymers, leading to materials with high strength despite relatively low crosslink density relative to that in previous biopolymer–sulfur composites. The low crosslink density resulted in relatively long polysulfur catenates, thus producing materials with impressive flexural strengths (5.3–5.4 MPa) and highlighting the potential for biomass–sulfur materials to exhibit a range of mechanical properties depending on the biopolymer scaffold and modification strategy.

In this study, kefiran was esterified with octenyl succinic anhydride (OSA). The esterification reaction variables including pH (8.5), kefiran concentration (5% (w/w)), OSA concentration (12% (w/w)), temperature (~38 °C) and reaction time (~80 min) were found as optimum points to achieve the maximum degree of substitution (DS) (0.041 ± 0.002). Kefiran-OSA samples with DS of 0.021 (FDA suggested DS) and 0.041 (maximum DS) were prepared and compared with unmodified kefiran in all experiments. FTIR and 1H NMR spectroscopies proved the grafting of OSA on kefiran structure. XRD analysis revealed that with increase in DS, the physical state of kefiran to be more amorphous. In addition, the esterification modification led to a decrease in the degradation temperature and an increase in the apparent viscosity based on the obtained data from thermal analysis and viscosity measurement. The results of the foaming and emulsifying properties confirmed the improvement in surface properties of the modified kefiran. The frequency sweep test illustrated that with an increase in DS, the viscoelastic behavior of the kefiran cryogels to be more viscous. It can finally be stated that the modification with OSA was a high potential strategy to extend the industrial applications of the kefiran.

The facile design and preparation of polyelectrolytes is a frontier topic in the fields of polymer science, energy storage devices and catalysis. Herein, linear water soluble cellulosic poly(protic ionic liquid) (CPIL) electrolytes were facilely and atom economically prepared after the dissolution of cellulose in the newly developed DBU/CO2/DMSO solvent system, followed by the simple addition of succinic anhydride under mild conditions. The DBU not only participated in the dissolution of cellulose as a solvent component, but also acted as an organocatalyst for the acylation reaction of cellulose with succinic anhydride, as well as a cation component in the targeted CPIL electrolytes. The reaction was optimized, and the effect of the reaction conditions on the chemical and physical properties of the CPILs was investigated. And then, as a proof of concept, the CPIL electrolyte aqueous solution was successfully used as the catalytic reaction media for the Knoevenagel condensation reaction. It was found that the reaction was homogeneous at the beginning, and the products could precipitate out from the media with the proceeding of the reaction, thus affording satisfactory filtration yields ranging from 56.7% to 93.8%. The solution properties of the CPIL aqueous solution were primarily investigated towards an in-depth understanding of the catalytic mechanism, by which a synergetic catalytic mechanism of the CPILs was proposed, and the reaction started with a nucleophilic addition reaction, and was then followed by a fast dehydration reaction. Finally, the direct reusability potential of the CPIL aqueous solution after the product filtration was also primarily investigated for the Knoevenagel condensation reaction.

Li metal is a promising anode material for next-generation energy storage systems owing to its high theoretical capacity and low potential. However, uncontrollable Li dendrite growth during Li plating and stripping results in low coulombic efficiencies and severe safety hazards. Herein, succinic anhydride (SA), an inexpensive and simple molecule, is investigated as a deposition-regulating additive. The relationship between the Li electrodeposition overpotential and the solvation structure of Li ions was systematically analyzed. Electrochemical tests and theoretical calculations indicate that strong complexation between Li+ and SA changes the solvation structure of Li+ and increases the energy barrier for Li deposition, resulting in a higher overpotential for Li electrodeposition. This increase in overpotential is conducive to generating more nucleation sites, reducing the Li nucleus size, and forming smooth Li deposits. XPS results also show that the addition of SA facilitates the formation of an improved SEI structure. Therefore, symmetric Li/Li cells with 3.0 wt% SA in the electrolyte exhibit excellent electrochemical performance over 300 cycles at 1.0 mA cm−2 with a capacity of 0.5 mA h cm−2. Enhanced cycling performance is also observed in Li/LiNi0.8Co0.1Mn0.1O2 full cells. Thus, SA can significantly alter the Li plating behavior, affording a promising strategy for suppressing Li dendrite growth in Li-metal-based batteries.

Two series of completely furfural-based poly(butylene succinate) (PBS) and poly(butylene 2,5-furandicarboxylate) (PBF) ternary-copolyesters were obtained by melt polycondensation of succinic anhydride (SA) or 2,5-furandicarboxylic acid (FDCA) with 1,4-butanediol (1,4-BDO) and tricyclic diacid (TCDA), leading to a total carbon utilization of furfural. Notably, a practical furfural-to-FDCA conversion process was demonstrated via K2CO3 promoted C–H carboxylation of furoate in molten sodium formate. The novel copolyesters displayed controllable thermal, mechanical and gas barrier properties over a wide range, in addition to crystallization behavior, by varying polymer composition using different feeds of the linear SA, planar FDCA and stereoscopic TCDA building blocks. In addition, a series of novel quadri-copolyesters (PBTCx(SnFm)y) with comparable properties to petrochemical-based plastics were synthesized from SA, FDCA, TCDA and 1,4-BDO. In particular, PBTC15(S10F90)85 exhibited satisfactory Tg (36.7 °C) and tensile strength (46.9 MPa) comparable to those of poly(butylene terephthalate) (PBT), in addition to superior ductility (eb = 830%) and CO2 barrier properties (0.029 barrer) when compared with poly(ethylene terephthalate) (PET). A strategy to convert furfural biomass into polymerizable monomers provides a feasible route in commercializing furfural and accessing a variety of novel renewable polyesters that are promising alternatives to existing commercial petrochemical-based polyesters.

A series of new chiral salenCo(III)X complexes [salen = (R,R)-N,N′-bis(3-R-5-tert-butylsalicylidene)-1,2-cyclohexanediamine, X− = OAc−, R = CMe2CHMe2 (4a), CPhMe2 (4b), CPh2Me (4c); X− = 2,4-dinitrophenoxide anion (DNP), R = CMe2CHMe2 (5a), CPhMe2 (5b), CPh2Me (5c); X− = Br−, R = CMe2CHMe2 (6a), CPhMe2 (6b), CPh2Me (6c)] with bulky substituents at the 3,3′-positions of the salicylidene moiety were synthesized and investigated as catalysts in the copolymerization of CO2/propylene oxide (PO) and the sequential copolymerization of succinic anhydride/PO and CO2/PO. The effects of the reaction conditions were examined by using complex 4b as a representative catalyst for the copolymerization of CO2/PO. It was found that catalysts with different ligands and axial coordinating groups show remarkable differences in their catalytic properties. The catalysts with relatively small R groups show relatively high catalytic activity and produce copolymers with relatively high molecular weights, while the catalysts with relatively bulky R groups show relatively high stereoselectivity. Catalyst systems employing 4-(dimethylamino)pyridine (DMAP) as the cocatalyst show relatively low catalytic activity but high stereoselectivity in comparison with the ones observed in the systems with bis(triphenylphosphoranylidene) ammonium chloride (PPNCl) or PPNDNP as the cocatalyst. With the catalyst system of 5c/DMAP, a high kinetic resolution coefficient (Krel) of 10.6 for the insertion of (S)-PO over (R)-PO was obtained at 25 °C. High molecular weight PPCs (Mw > 100 kg mol−1) were prepared with 5a/PPNCl and 5a/PPNDNP catalyst systems. Stereoregular block copolymers poly(propylene succinate-block-carbonate) were obtained from sequential copolymerization via catalytic kinetic resolution.

Gum arabic with multialdehyde groups (GAMA) was synthesized and utilized as a naturally derived macromolecular and nontoxic cross-linker to develop biocompatible and smart succinic anhydride-modified chitosan (SCS)-based injectable hydrogels for the first time. Aqueous solutions of GAMA and SCS were mixed at 37 °C to obtain hydrogels through pH-responsive, dynamic, and biodegradable Schiff base linkages. The effect of concentration of GAMA on hydrogel stiffness, swelling, morphology, and drug release behavior was investigated. These hydrogels exhibited outstanding self-healing and mechanical properties. Nanocurcumin as a chemotherapeutic agent was synthesized and loaded into these hydrogels for release studies carried out at pH 7.4 and 5.5. MTT assay revealed that these hydrogels are nontoxic to human embryonic kidney cell line (HEK-293). Loaded hydrogels demonstrated significant cytotoxicity against breast cancer cell line (MCF-7). Thus, the present strategy may find promising application for controlled delivery of anticancer drugs for treating locally accessible cancers.

Polyisobutenyl succinic anhydrides (PIBSAs) and their succinimide derivatives are one of the most important additives in lubricant and fuel formulations. These additives are commonly synthesized th...

Hamidreza Mohammadi,1,2 Reza Heidari,1 Seyyed Vahid Niknezhad,1 Akram Jamshidzadeh,1,2 Fatemeh Farjadian1 1Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; 2Department of Pharmacology and Toxicology, Faculty of Pharmacy, Shiraz University of Medical Sciences, Shiraz, IranCorrespondence: Fatemeh FarjadianPharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, P. O. Box 158371345, Karafarin Ave., Shiraz, Fars, IranTel + 987132424127 302Fax + 987132424126Email farjadian_f@sums.ac.irAkram JamshidzadehDepartment of Pharmacology and Toxicology, Faculty of Pharmacy, Shiraz University of Medical Sciences, P. O. Box 158371345, Karafarin Ave., Shiraz, Fars, IranEmail ajamshid@sums.ac.irPurpose: Hepatic encephalopathy (HE) is a critical situation in which liver failure affects brain function. HE could result in a state of coma and death. The liver is the main organ for ammonium ion (NH4+) metabolism. Hence, acute and/or chronic liver failure could lead to hyperammonemia. NH4+ is the most suspected neurotoxic agent in HE. Thus, finding new therapeutic options to decrease plasma and brain NH4+ levels has a significant clinical value. Mesoporous silica (MS) particles have revolutionized many aspects of pharmaceutical sciences, including drug delivery systems. Moreover, recently, MS has been applied as agents for the detoxification of chemicals (eg, drugs and poisons).Methods: First, MS particles containing amine groups (MS-NH2) were synthesized in co-condensation processes. Then, the structure was modified by succinic anhydride to have MS-SA. The MS-SA was characterized (FT-IR, XRD, X-ray photoelectron spectroscopy (XPS), DLS-Zeta FESEM-EDX, and HRTEM). Then, the potential of MS-NH2 and MS-SA particles in adsorption of NH4+ was investigated in vitro and in vivo. MS-NH2 and MS-SA were incubated with increasing concentrations (0.1– 10 mM) of NH4+, and the scavenging capacity of the investigated particles was evaluated. On the other hand, different doses (1 and 5 mg/kg per day) of nanoparticles were administered to a hyperammonemia animal model.Results: It was figured out that both MS-NH2 and MS-SA significantly scavenged NH4+ in the in vitro model. However, the NH4+ scavenging capability of MS-SA was more significant. Administration of MS-NH2 and MS-SA also considerably decreased the level of ammonium in plasma and brain and improved cognitive and locomotor activity in hyperammonemic animals. The effects of MS-SA were more significant than MS-NH2 in the HE animal model.Conclusion: Collectively, our data suggest that MS particles, especially succinic acid-functionalized MS, could act as special ancillary treatment in HE as a critical clinical complication.Keywords: acute liver failure, ammonia, hyperammonemia, nanomedicine

Pullulan (PU) is an exo-polysaccharide used in the food and pharmaceutical industries. However, the use of PU in different industries is limited due to its highly hydrophilic nature and consequently weakness in surface properties which can be remedied by its chemical modification with octenyl succinic anhydride (OSA). For this purpose, PU modification with OSA was optimized and the results showed that the maximum degree of substitution (0.061 ± 0.003) was obtained under pH of 9.0, pullulan concentration of 40% (w/w), temperature of ~40.90 °C, reaction time of ~101.21 min and OSA concentration of 14.96% (w/w). Also, the grafting of OSA on pullulan structure was confirmed by FTIR, 1H NMR and zeta-potential analyzes. Although this modification had no significant effect on the amorphousity of pullulan, it led to an increase in viscosity and a decrease in decomposition temperature and surface tension. Improvement of emulsifying properties of PU-OSA sample was proved by the evaluation of emulsifying capacity of un- and modified samples and also, zeta-potential, particle size and viscosity of the prepared emulsions. In line with surface characteristic results, an increase in foam capacity of modified samples was observed with decreasing the interfacial tension.

We are exploiting the use of a versatile catalyst taken from heterogeneous catalysis, i.e., ZrOCl2.8H2O to efficiently catalyze the reaction of dextran-succinate conjugate (Dex-SAn) with salicylic acid (SA) under homogeneous reaction conditions. Dextran was first linked with succinic anhydride using triethylamine as a base in DMAc to provide active functionalities (succinate moieties) situated away from the polymer chains. The resultant Dex-SAn conjugate was further esterified with SA using zirconium (IV) oxychloride octahydrate (ZrOCl2.8H2O) as a catalyst at 80 °C under N2. Reaction conditions and amount of catalyst ZrOCl2.8H2O and chiral support MCM-41 were optimized. This reaction methodology resulted in macromolecular prodrugs of SA as Dex-SAn-SA conjugates in good yield. The structures of Dex-SAn and newly synthesized Dex-SAn-SA conjugates were characterized using various spectroscopic techniques, i.e., FT-IR, 1H, and APT-13C NMR spectroscopy. The degree of substitution of SA on to Dex-SAn-SA was determined by UV/Vis spectroscopic methods. This reaction methodology can be modeled as a new protocol for facile attachment of several drug molecules onto the highly potential and biodegradable drug carrier dextran.

Granular starch octenyl succinic anhydride (OSA) esters have most often been prepared in aqueous media, resulting in low reaction efficiencies and degree of substitution. In this study, granular ma...

Detecting microRNA (miRNA) biomarkers expression is of great significance for the diagnosis and treatment of lung cancer. Surface-enhanced Raman scattering (SERS) has achieved microRNA sensing for the diagnosis of primary liver cancers. In this work, we developed a SERS technology for the rapid detection of lung cancers-related miRNA (miR-196a) using bimetallic Au-Ag nanowire (AgNW@AuNPs) substrates coupled with the target hairpin DNA. The finite-difference time-domain simulation proved that a large number of “hot spots” were generated between the AgNW and AuNPs, which resulted in a huge enhancement of the signal of Raman reporters. Filter paper treated by hexadecenyl succinic anhydride hydrophobic and modified with AgNWs@AuNPs was used as capturing substrate. The detection limits of miR-196a in PBS and serum were as low as 96.58 aM and 130 aM, respectively. Studies on nonspecific sequence and single-base mismatch of miRNA demonstrated that SERS-based platform was highly selective, excellent uniform, and reproducible. Finally, the platform was used to show that the miR-196a expression in the serum of lung cancer patients was much higher than that in healthy people. The detection results indicated that the SERS platform had potential applications in cancer diagnosis and might be a viable alternative to the conventional miRNA detection method, the real-time polymerase chain reaction (RT-PCR) technology.

Typical ring-opening copolymerization (ROCOP) of cyclic anhydrides (A) and epoxides (B) catalyzed by most metal complexes underwent strict alternating monomer insertions giving (AB)ₙ polyesters. In this contribution, a novel polyester containing (ABB)ₙ polymer sequences was prepared via the ROCOP of cyclic anhydrides and cyclohexene oxide (CHO) using a tin(II) alkoxide complex. Quantum calculations revealed that the preference for the (ABB)ₙ sequence was enhanced by the energetic preference of the second CHO insertion. The copolymer with (ABB)ₙ content as high as 70% was obtained from the ROCOP of succinic anhydride and CHO with an enhanced Tg of 65 °C (>20 °C higher than the (AB)ₙ analogue). The ROCOP of maleic anhydride and CHO also gave a copolymer with high (ABB)ₙ content at 48% and improved Tg of 89 °C (38 °C higher). The improved thermal properties were a result of the more rigid (ABB)ₙ polymer backbone compared with conventional alternating (AB)ₙ copolymer analogues. In addition, terpolymerization with e-caprolactone (e-CL) was achieved by sequential addition of e-CL affording the block copolymer with the (ABB)ₙ backbone.

Efficient and reliable synthesis of substituted hydrazinylpyridines in thick-wall ACE tubes via nucleophilic substitution of a chlorine substituent in different chloropyridines is presented. Hydrazine hydrate and alkylhydrazines were used as nucleophiles and simple alcohols and diethyl ether were the only organic solvents necessary, making the process environmentally and user friendly, potentially reaching 100% atomic efficiency. In the next step, transformations of succinic anhydride moieties fused to the bicyclo[2.2.2]octene framework into succinimide moieties via nucleophilic substitution of oxygens were conducted. As nucleophiles two of the synthesized hydrazinylpyridines (2-hydrazinyl-3-nitropyridine and 2-hydrazinyl-5-nitropyridine) and also hydrazine hydrate, phenylhydrazine, and 4-nitrophenylhydrazine were used. Reactions were again carried out in ACE tubes and only simple alcohols, diethyl ether, and acetone were needed as solvents. One of the prepared bicyclo[2.2.2]octene adducts displayed water solubility thus being a promising candidate for future studies as a novel bidentate ligand for various metal cations in aqueous solutions or acting as an unprecedented halogen bond acceptor.

Narrow distribution pullulan (PUL) samples with different degrees of polymerization (=142–4540) were reacted with octenyl succinic anhydride (OSA) to obtain a hydrophobically modified pullulan (PUL...

Phytoglycogen is a highly branched polymer of glucose produced as soft, compact nanoparticles by sweet corn. Properties such as softness, porosity, and mechanical integrity, combined with nontoxicity and biodegradability, make phytoglycogen nanoparticles ideal for applications involving the human body, ranging from skin moisturizing and rejuvenation agents in personal care formulations to functional therapeutics in biomedicine. To further broaden the range of applications, phytoglycogen nanoparticles can be chemically modified with hydrophobic species such as octenyl succinic anhydride (OSA). Here, we present a self-consistent model of the particle structure, water content, and degree of chemical modification of the particles, as well as the emergence of well-defined interparticle spacings in concentrated dispersions, based on small-angle neutron scattering (SANS) measurements of aqueous dispersions of native phytoglycogen nanoparticles and particles that were hydrophobically modified using octenyl succinic anhydride (OSA) in both its protiated (pOSA) and deuterated (dOSA) forms. Measurements on native particles with reduced polydispersity have allowed us to refine the particle morphology, which is well described by a hairy particle (core-chain) geometry with short chains decorating the surface of the particles. The isotopic variants of OSA-modified particles enhanced the scattering contrast for neutrons, revealing lightly modified hairy chains for small degrees of substitution (DS) of OSA, and a raspberry particle geometry for the largest DS value, where the OSA-modified hairy chains collapse to form small seeds on the surface of the particles. This refined model of native and OSA-modified phytoglycogen nanoparticles establishes a quantitative basis for the development of new applications of this promising sustainable nanotechnology.

A silane unit with enhanced synergism that is realized using one cationic quaternary ammonium salt (QAS) to draw anionic bacteria to two N-halamine functionalities was designed and polymerized on cellulose for superior biocidability. A monomer containing one tertiary amine, one amide N–H, and one imide N–H, was synthesized via alcoholysis of 3-triethoxysilylpropyl succinic anhydride with 2-(dimethylamino)ethan-1-ol and following esterification with 5-(4-hydroxyphenyl)hydantoin. The triethoxysilyl groups of the monomer were hydrolyzed to silanol groups to condense with counterparts in different hydrolyzates and with hydroxyl groups on cellulose to form a polymeric modifier. Each silane unit of the modifier has one QAS and two N-halamine functionalities (quat/di-N-halamines) after quaternization of the tertiary amine and chlorination of the amide and imide hydrogens. The resultant cellulose suppressed (7 logs) both Staphylococcus aureus and Escherichia coli within 3 min, demonstrating an enhanced synergism since the inactivation rate is faster than counterparts decorated with only N-halamine and with synergistic units of one cationic center and one N-halamine. The modifier exhibited promising stability and rechargeability toward washings, UV irradiation, and long-term storage. The proved enhanced synergism from the integration of one cationic center with multiple N-halamines directs the synthesis of more powerful biocides for developing antibacterial polymers.

The Castagnoli–Cushman reaction of 3,4-dihydroisoquinolines with glutaric anhydride, its oxygen and sulfur analogues was investigated as a one-step approach to the benzo[a]quinolizidine system and its heterocyclic analogs. An extension towards the pyrrolo[2,1-a]isoquinoline system was achieved with the use of succinic anhydride. The results are evidence of an unexplored method for the access of the aforementioned tricyclic annelated systems incorporating a bridgehead nitrogen atom. The structures and relative configurations of the new compounds were established by means of 1D and 2D NMR techniques. The reactions between 1-methyldihydroisoquinoline and glutaric, diglycolic and succinic anhydrides yielded unexpected isoquinoline derivatives containing an exocyclic double bond. The compounds prepared bear the potential to become building blocks for future synthetic bioactive molecules.

The development of gel-like Pickering emulsions stabilized by edible particles has attracted significant interest in the food colloid field. This work reported that starch nanocrystals (SNCs), modified by octenyl succinic anhydride (OSA), could introduced as a natural stabilizer for gel-like Pickering emulsions. The formation, microstructure and stability of Pickering emulsions were characterized by visual observations and optical microscopy. The results indicated that surface modification improved the hydrophobicity and aqueous re-dispersibility of SNCs, as well as the emulsification performance of them. The stable gel-like Pickering emulsions were formed at different oil volume fractions (range from 40% to 74%), increasing the degree of substitution (DS: from 0.010 to 0.018) led to gel-like emulsion stronger stiffness. These findings offer a promising opportunity to develop a kind of novel edible gel-like Pickering emulsions stabilized by OS-SNCs for the food and pharmaceutical industries.