Beta-Cyclodextrin as Carbon Source for Synthesis of LiFePO_4/C with Improved Electrochemical Properties in Lithium-ion Batteries

For beta-cyclodextrin (β-CD) may form complexes with metal ions during ballmilling process, it was used as a novel carbon source to synthesize LiFePO_4/C cathode composite in lithium-ion batteries via solid-state reaction. This composite should has fine particle size and good electrochemical performances. The powders were characterized by XRD, SEM, TEM and galvanostatic charge-discharge. Compared with bare LiFePO_4 and LiFePO_4/C composite with glucose as carbon source by the same procedure and nearly the same content of carbon in the final cathode, the LiFePO_4/C composite with beta-cyclodextrin as carbon source shows much higher discharge specific capacity and more excellent rate performance. Ultrasonic dispersion between ballmilling and sinter process for 2 h was appropriate and useful for final LiFePO_4/C to reach higher discharge capacity. The SEI experiment was carried out to explore the effect of beta-cyclodextrin on the cathode materials, and the results indicate that coating with beta-cyclodextrin can improve the electrochemical performance of LiFePO_4 by decreasing the resistance of charge transfer (R_ ct) and improving the chemical diffusion coefficient (D_ Li).

THERMAL-SENSITIVE BETA-CYCLODEXTRIN-CONTAINING POLY(NISOPROPYLACRYLAMIDE)HYDROGELS CROSSLINKED BY Si—O—Si BONDS—SYNTHESIS,CHARACTERIZATION AND PROLONGING IN VITRO RELEASE OF 5-FLUOROURACIL

A series of novel p（N-isopropylacrylamide） （PNIPAM） hydrogels were synthesized by radical copolymerization of N-isopropylacrylamide （NIPAM） and 3-methacryloxypropyltrimethoxysilane （MPTMS）. The copolymers were then crosslinked through hydrolysis of the siloxane in acetic acid/water mixed solvent. Beta-cyclodextrin （Beta-CD） was introduced into the polymeric networks by condensation of 3-glycidoxypropyltrimethoxysilane derived beta-cyclodextrin （KH560-beta-CD） with MPTMS under acidic condition. These gels were heterogeneous, porous and exhibited fast deswelling kinetics when the temperature was elevated to above lower critical solution temperature （LCST）. The swelling ratios of the gels containing beta-CD at room temperature were higher than that of the normal PNIPAM hydrogel, which was caused by the lower crosslinking density in beta-CD contained gels. In comparison to that of the normal PNIPAM gel, the amount of loaded-drug in the hydrogel containing beta-CD was higher, and the release time of 5-fluorouracil （5-Fu） was prolonged, which was attributed to the formation of inclusion compounds between 5-Fu and beta-CD in gel network.

Influence of Beta-Cyclodextrin Functionalized Tin Phenylphosphonate on the Thermal Stability and Flame Retardancy of Epoxy Composites

To enhance the thermal stability and flame retardancy of epoxy resin(EP),beta-cyclodextrin(β-CD)is successfully introduced into the layered tin phenylphosphonate(SnPP),which is incorporated into EP matrix for preparing EP/β-CD@SnPP composites.The results indicate that the addition ofβ-CD@SnPP obviously improve the thermal stability and residual yield of EP composites at higher temperature.When the amount ofβ-CD@SnPP is only 4 wt%,EP/4β-CD@SnPP composites pass V-1 rating,and LOI value is up to 30.8%.Meanwhile,β-CD@SnPP effectively suppress the heat release and reduce the smoke production of EP/β-CD@SnPP composites in combustion,and the peak heat release rate(PHRR),total heat release(THR),smoke production rate(SPR)of EP/6β-CD@SnPP composites reduce by 28.4%,33.0%and 44.8%by comparison with those of pure EP.The good flame retardancy and smoke suppression are ascribed to the synergistic effect of excellent carbon-forming capability and fire retardancy ofβ-CD@SnPP.

Method for quantification of prazosin in dog plasma and its application to pharmacokinetic study

A simple and sensitive high performance liquid chromatography method using fluorescence detection （HPLC- FLD） and a one-step single solvent extraction for the determination of prazosin（PZS） in dog plasma is developed and validated. After extraction with ether, the chromatographic separation of PZS is carried out using a reverse phase C18 column （ 150 mm ×4.6 mm, 5 μm） with a mobile phase of 30% acetonitrile and 70% acetic acid-sodium acetate buffer solution （pH = 3.6） and quantified by fluorescence detection operated with an excitation wavelength of 258 nm and an emission wavelength of 387 nm. The flow rate of the mobile phase is 1.0 mL/min and the retention time of PZS and the internal standard is found to be 4. 4 and 5. 8 rain, respectively. The calibration curve is linear within a concentration range from 1.0 to 1 000.0 ng/mL （ P 〉 0. 998）. The limit of detection is 0.4 ng/mL. The inter-day coefficient of variation （COV） of the calibration standards is below 5.0% and the mean accuracy is in the range from 92. 7% to 104. 2%. Moreover, by analyzing quality control plasma samples for three days, the results show that the method is precise and accurate, for the intra- and inter- day COV within 10% and the accuracy from 95.9% to 112.7%. The developed and validated method is successfully applied to phannacokinetic study for the preclinical evaluation of a new peroral PZS-sulfobutyl ether beta-cyclodextrin （PZS-SBE-β-CD） inclusion complex tablets （test preparation）, which demonstrates that the test preparation released PZS is conducted in a slow and controlled way, and the relative bioavailability of the test preparation is found to be 105.0%.

Synthesis of Novel Chitosan Microspheres Grafted with β-Cyclodextrins and Their Adsorption for Iodine for Antibacterial Activities

The novel chitosan microspheres grafted with beta-cyclodextrins (CMGC) wereprepared by means of the reaction of chitosan microspheres and mono-(6-p-tosyl)- beta-cyclodextrins(beta-CD-OTs-6). beta-CD-OTs-6 were gained by the reaction of p-toluenesul-fonyl chloride (TsCl) andbeta-cyclodextrins (beta-CDs). Their structures were proved by Fourier transform infrared spectralanalysis (FT-IR), X ray powder diffraction analysis, and ^(13)C NMR; the configuration of CMGC wascharacterized by scanning electron micrograph (SEM) and transmittance electron micrograph (TEM). Theinclusion complex of CMGC with iodine was prepared and its inclusion ability was studied. Theexperimental results showed that some iodine was included with CMGC and formed a stable inclusion.The stable complex of CMGC and iodine (CMGC-1) shows good antibacterial effect.

Binding Affinity of Novel Cyclodextrin Dimers to Ethyl Orange

The interaction between ethyl orange (Eto, guest) and beta-cyclodextrin dimers (1asimilar tod, host) bridged with 2-t-butoxycarbonyl(Boc)-amino diacid was investigated. A remarkable synergic complexation of two cavities in host molecule was observed.

Beta-cyclodextrin adsorbents to remove water pollutants-a commentary

Beta-cyclodextrin-based adsorbent is a promising adsorbent because it has unique characteristics and able to form host-guest complexes with various organic compounds.Adsorption using beta-cyclodextrin-based adsorbent has continuously improved by various preparation strategies and crosslinking agents.This commentary aims to highlight the preparation strategies,properties,and adsorption mechanisms of beta-cyclodextrin-based adsorbents.The adsorbents can be generally classified according to the preparation methods and display high adsorption capacity especially for dyes.Particularly,composite/nanocomposite beta-cyclodextrin-based adsorbents exhibit outstanding adsorption capacity even though the surface area is lower than that of porous and magnetic betacyclodextrin-based adsorbents.The beta-cyclodextrin/chitosan functionalized graphene oxide hydrogel with specific surface of 17.6 m^(2)·g^(–1)yields an extraordinarily maximum adsorption capacity of 1499 mg·g^(–1)methylene blue,while beta-cyclodextrin/chitosan modified with iron(Ⅱ,Ⅲ)oxide nanoparticles displays a much greater maximum adsorption capacity at 2780 mg·g^(–1).The hydrophobic interaction,functional groups,hydrogen bonding,and electrostatic interaction govern the adsorption to a greater capacity.Although this commentary is not exhaustive,the preparation strategies and illustrated mechanisms provide useful insights into the adsorbent–adsorbate interactions,costeffective analysis,challenges,and future directions of betacyclodextrin-based adsorbents in wastewater treatment.