Kyedlowe9575

Dimethyl sulfoxide (DMSO) is an excellent solvent for various types of anticancer drugs. Here, beyond that, it can participate in a disulfide bond crosslink between sulfhydryl (-SH) modified hyaluronic acid (HA-SH) molecules to form the hydrogel. Thus, during the above crosslink process, the dissolved drug in DMSO could be effectively loaded inside the hydrogels' porous structures as an injectable peritumoral implant. The loaded drugs can be sustained released through hydrogel swelling and degradation around the tumor tissue to suppress tumor growth. In this paper, the above hydrogel was used as a peritumoral drug-loaded implant for chemotherapeutics, photosensitizer, and photothermal reagent, respectively, for chemotherapy, photodynamic therapy, and photothermal therapy in cancer treatment. Therefore, this DMSO involved HA-SS-HA (HA, hyaluronic acid; -SS-, disulfide bond) hydrogel fabrication method is simple and widely applicable for drug-loaded peritumoral implant preparation.Chondroitin sulfate (CS)-calcium complex (CSCa) was fabricated, and the structural characteristics of CSCa and its proliferative bioactivity to the chondrocyte were investigated in vitro. Results suggested calcium ions could bind CS chains forming polysaccharide-metal complex, and the maximum calcium holding capacity of CSCa reached 4.23 %. Characterization of CSCa was performed by EDS, AFM, FTIR, UV, XRD and 1H-NMR. It was found that calcium ions were integrated with CS by binding the sulfate or carboxyl groups. The thermal properties analysis indicated CSCa had a good thermal stability by TGA and DSC. CSCa could interact the calcium-sensing receptor increasing the intracellular calcium ions and influence the cell cycle. The TGF-β1 secretion induced by CSCa could activate the TGF-β/Smads pathway and change the genes associated proliferation expression ultimately leading to the chondrocyte proliferation. This research probably has an important implication for understanding the effect of CSCa on bone care as food supplements.Practical application of powder photocatalysts is far from satisfying due to their low photon utilization, inconvenient recovery and potential environmental risk. In this study, an easily recoverable, environmentally friendly and highly transparent floatable magnetic photocatalyst carrier was prepared based on biopolymer alginate and Fe3O4 particles. Further, three different types of photocatalysts were chosen as model semiconductor photocatalysts and loaded on the shell of the carriers. The freeze process facilitated the formation of internal cavities that enhanced floating ability and transparency of the spheres. Meanwhile, the excellent floating performance offered massive reaction sites for pollutants reacting with photocatalysts, O2 and photons on the air/water interface. Photodegradation results showed all three floatable hybrid photocatalysts exhibited enhanced photocatalytic efficiencies compared to the virgin photocatalysts. In short, the carrier can integrate excellent floating ability, environmental friendliness and full recycling with good stability, and it can greatly improve the photocatalytic efficiency of various powder semiconductor photocatalysts.Polysaccharides have been used widely in many industries, from food technology and mining to cosmetics and biomedical applications. Over recent years there has been growing interest in the development of responsive polysaccharides with unique and switchable properties, particularly systems that display lower-critical solution temperatures (LCSTs). Therefore, in this study we aimed to investigate a novel strategy that would allow the conversion of non-responsive polysaccharides into thermoresponsive polysaccharides with tuneable LCSTs. Through the functionalisation of dextran with alkylamide groups (isopropyl amide, diethyl amide, piperidinyl and diisobutyl amide) using a carbodiimide coupling approach in conjunction with amic acid derivatives, we prepared a library of novel dextrans with various degrees of substitution (DS), which were characterised via nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC). The alkylamide-functionalised dextrans were found to have good solubiliresponsive properties and trends that may make them useful in biomedical applications, such as drug-delivery.We use acetylated cellulose nanofibrils (AcCNF) to stabilize transient emulsions with paraffin that becomes shape-stable and encapsulated phase change material (PCM) upon cooling. Rheology measurements confirm the gel behavior and colloidal stability of the solid suspensions. We study the effect of nanofiber content on PCM leakage upon melting and compare the results to those from unmodified CNF. see more The nanostructured cellulose promotes paraffin phase transition, which improves the efficiency of thermal energy exchange. The leakage-proof microcapsules display high energy absorption capacity (ΔHm = 173 J/g) at high PCM loading (up to 80 wt%), while effectively controlling the extent of supercooling. An excellent thermal stability is observed during at least 100 heating/cooling cycles. Degradation takes place at 291 °C, indicating good thermal stability. The high energy density and the effective shape and thermal stabilization of the AcCNF-encapsulated paraffin points to a sustainable solution for thermal energy storage and conversion.A new model is proposed for the kinetics of the heterogeneous deacetylation of chitin/chitosan. This new model is able to represent the process over much broader ranges than the other kinetic models reported in the literature. The unreacted shrinking core model was modified with the inclusion of increasing diffusional effects as the reaction progresses, causing the rate to slow down and preventing the degree of deacetylation reaching 100 %, even in the presence of excess NaOH. The model was validated with data collected in experiments with different NaOH concentrations and temperatures. The proposed model was able to represent the experimental data correctly over the entire experiment span, resulting in a model with proven predictive ability, in contrast to existing kinetic models that have been applied in a piecewise fashion over a rather limited time range of the process. The proposed model represents an improvement in the understanding of the deacetylation process.In current study, the effects of starch fine molecular structures on its in vitro digestibility at fully gelatinized stage were investigated. The digestion kinetics of 15 fully gelatinized rice starches were obtained and correlated with starch chain-length distributions and molecular size distributions. Both logarithm of slopes and parallel first-order kinetic model were applied to fit the digestion curves to a few kinetics-based parameters. Result showed there were two simultaneous digestion fractions (fast versus slow) for fully gelatinized rice starches. The rate constants of slowly-digestible fraction significantly correlated with starch molecular sizes, especially with that of amylopectin molecules. Hydrodynamically larger amylopectin molecules tend to contain more shorter branches but less long chains. This slows down the starch hydrolysis by α-amylase while the action of AMG is less antagonistically hindered, increasing overall digestion rate. This study provides important information for rice breeders and manufacturers to develop rice products with reduced starch digestibility.Dispersion of cellulose nanocrystals (CNCs) is of utmost importance to guarantee their reliable application. Nevertheless, there is still no consensual method to characterize CNC aggregation. The hypothesis of this paper is that dispersion could be quantified through the classification of aggregates detected in transmission electron microscopy images. k-Means was used to classify image particulate elements of five CNC samples into groups according to their geometric features. Particles were classified into five groups according to their maximum Feret diameter, elongation, circularity and area. Two groups encompassed the most application-critical aggregates one integrated aggregates of high complexity and low compactness while the other included elongated aggregates. In addition, the characterization of CNC dispersion after different levels of sonication was achieved by assessing the change in the number of elements belonging to each cluster after sonication. This approach could be used as a standard for the characterization of the aggregation state of CNCs.One-pot fabrication of sacchachitin (SC) for mass-production was developed and optimized by selecting KOH as alkaline agent in depigmentation step and utilizing NaClO2 as bleaching agent in subsequent step in the same pot. Overall yield of one-pot-fabricated SC was up to 35 %w/w of initial weight with a fibrous texture soft enough for mechanical disintegration into SC nanofibers (SCNFs) and better dispersion for producing TEMPO-oxidized SCNFs (T033SC). Both SCNFs and T033SC could form a 3D gelatinous scaffold into which MC3T3-E1 cells were attracted. Higher calcium-trapping ability of T033SC resulting from a greater extent of carboxylate groups provided an excellent bone regeneration environment that resulted in better outcomes of bone regeneration in a femur defect rat model compared to those with SCNFs possessed fewer carboxylate groups. In conclusion, biomaterial scaffolds based on TEMPO-oxidized SCNFs produced from one-pot fabricated SC showed great potential for bone regeneration due to unique physical and chemical properties.A novel theranostic nanoplatform was prepared based on Fe3O4 nanoparticles (NPs) coated with gadolinium ions decorated-polycyclodextrin (PCD) layer (Fe3O4@PCD-Gd) and employed for Curcumin (CUR) loading. The dissolution profile of CUR indicated a pH sensitive release manner. Fe3O4@PCD-Gd NPs exhibited no significant toxicity against both normal and cancerous cell lines (MCF 10A and 4T1, respectively); while the CUR-free NPs showed more toxicity against 4T1 than MCF 10A cells. In vivo anticancer study revealed appropriate capability of the system in tumor shrinking with no tissue toxicity and adverse effect on body weight. In vivo MR imaging of BALB/c mouse showed both T1 and T2 contrast enhancement on the tumor cells. Fe3O4@PCD-Gd/CUR NPs showed significant features as a promising multifunctional system having appropriate T1-T2 dual contrast enhancement and therapeutic efficacy in cancer theranostics.An integrated treatment coupling ultrasonic and hydrothermal pretreatments with sequential alkali post-extractions was performed to isolate and characterize hemicelluloses from perennial ryegrass and improve the enzymatic hydrolysis efficiency of cellulose. The yield, chemical composition, and structure of water-soluble and alkali-soluble hemicelluloses obtained from the hydrothermal supernatant and hydrothermally pretreated ryegrass as well as the enzymatic hydrolysis efficiency of cellulose were comprehensively investigated by gel permeation chromatograph, high-performance anion exchange chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectra. Results showed that more than 90 % of the original hemicelluloses in ryegrass were released during the integrated treatment and all hemicellulosic fractions obtained were mainly composed of ʟ-arabino-(4-O-methyl-ᴅ-glucurono)-ᴅ-xylans, galactoanrabinoxylans and β-glucans. In addition, the effective removal of amorphous hemicelluloses and lignin significantly increased the cellulose enzymatic hydrolysis rate of ryegrass from 43.