Glycine-β-cyclodextrin-assisted cometabolism of phenanthrene and pyrene by Pseudomonas stutzeri DJP 1 from marine sediment

Cometabolic degradation is currently an effective and extensively way to remove high molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs).Unfortunately,due to low bio-accessibility and high biotoxicity,the cometabolic degradation rate of HMW-PAHs is limited.Glycine-β-cyclodextrin(GCD)was obtained through amino modification ofβ-cyclodextrin(BCD)and added to cometabolic system of phenanthrene(PHE)and pyrene(PYR)to assist PYR biodegradation.Results show that the addition of GCD(100 mg/L)effectively improved the removal rate of PYR(20 mg/L)by 42.3%.GCD appeared to increase the bio-accessibility and reduce the biotoxicity of PHE and PYR,and then promoted the growth of Pseudomonas stutzeri DJP1 and stimulated the elevation of dehydrogenase(DHA)and catechol 12 dioxygenase(C12O)activities.The phthalate metabolic pathway was accelerated,which improved the cometabolic degradation.This study provided a new reference for the cometabolic degradation of HMW-PAHs.

Morphological Evolution of Self-Assembled Sodium Dodecyl Sulfate/Dodecyltrimethylammonium Bromide@Epoxy-β-Cyclodextrin Supramolecular Aggregates Induced by Temperature

Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interaction with guest molecules.The different forms of supramolecular self-assemblies can be transformed into each other under certain conditions.The regulation of supramolecular self-assembly is not only helpful to understand the self-assembly principle,but also beneficial to its application.In the present study,the self-assembly behavior of epoxy-β-cyclodextrin(EP-β-CD)and mixed anionic and cationic surfactant system(sodium dodecyl sulfate/dodecyltrimethylammonium bromide,SDS/DTAB)in aqueous solution was studied.Morphological and particle size characterization found that the SDS/DTAB@EP-β-CD complex,as the basic building unit,self-assembled into worm-like micelles at lower temperatures and vesicles at higher temperatures.Nuclear magnetic resonance(NMR)and Fourier transform infrared spectroscopy(FT-IR)analysis revealed that the driving force for the formation of vesicles and worm-like micelles was the hydrogen bonds between EP-β-CD molecules,while water molecules played an important role in promoting vesicle formation between SDS/DTAB@EP-β-CD units.Herein,the mechanism of the morphologic transformation of SDS/DTAB@EP-β-CD supramolecular aggregates induced by temperature was elucidated by exploring the self-assembly process,which may provide an excellent basis for the development of delivery carriers.

Lyophilization Process of Hydroxypropyl Tetrahydropyrantriol Liposomes

[Objectives]To enhance the skin permeability of hydroxypropyl tetrahydropyrantriol and provide a reference for the subsequent prevention or treatment of skin aging.[Methods]The lyophilization process of hydroxypropyl tetrahydropyrantriol liposomes was investigated using a single factor method,and a quality evaluation system was established based on the appearance,particle size,PDI,and re-dispersibility of the lyophilized samples.[Results]The lyophilization process of hydroxypropyl tetrahydropyrantriol liposomes was determined by single factor experiments.The pre-freezing period was 16 h at-80℃,the total drying time was 36 h,and the addition of 10%mannitol-sucrose was used as the lyoprotectant.[Conclusions]The product prepared by the lyophilization method exhibits a fluffy and full appearance,with minimal shrinkage and collapse.The volume remains consistent before and after lyophilization,and the re-dispersibility is satisfactory.The re-dissolution process is rapid,and the particle size and polydispersity index(PDI)remain largely unchanged before and after lyophilization.

Synthesis and Characterization of β-Cyclodextrin Modified Biochar Environmental Remediation Materials

In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cyclodextrin (β-CD) was used to modify biochar (BC). The prepared modified biochar materials were labeled with β-CDBC, β-CDBC-Na, β-CDBC-CA and β-CDBC-H, respectively. The infrared spectrum, X-ray diffractometer, scanning electron microscope and specific surface area of the four modified materials were tested. The results showed that the C-O stretching vibration peak at 1020 cm−1 of the modified materials was slightly offset compared with that of biochar. The characteristic absorption peaks of XRD pattern decrease obviously at 2θ = 26.7˚ and 29.5˚. It can be obviously observed on the electron microscope image that the surface is loaded or formed clathrates, and BET data and graphs also show that the specific surface area of the modified biochar is larger. Therefore, β-cyclodextrin successfully modified biochar and formed clathrates on the surface of biochar or was loaded in the pore structure of biochar, especially β-CDBC-CA achieved better modification effect. Because biochar and β-cyclodextrin raw materials are cheap, easy to prepare and green, and less prone to secondary pollution, it has a good advantage in environmental governance.

Inclusion complex of tamibarotene with hydroxypropyl-β-cyclodextrin: Preparation,characterization, in-vitro and in-vivo evaluation

The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-cyclodextrin(Am80-HP-β-CD)was prepared through a freeze-drying method at the mole ratio of 1:1(Am80:HP-β-CD).Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry(DSC)indicated the formation of Am80-HP-β-CD.In vitro dissolution studies showed that the solubility and dissolution percentage of Am80-HP-β-CD was improved substantially compared to Am80.An improved dissolution with approximately 97%drug release in 3 min was observed,in comparison with Am80 with approximately 60% release in 45 min.In vivo studies indicated that the AUC0-∞ has increased 2.79 times and the Cmax 4.37 times after the formation of inclusion complex.The decrease of tmaxindicated the Am80-HP-β-CD inclusion complex can be absorbed into blood faster.In short,the solubility and bio-availability of Am80 has notably increased with the complexation of HP-β-CD.Therefore,using the inclusion technique is a promising method to improve the solubility of insoluble drugs.

Synthesis of Hydroxypropyl-β-cyclodextrin Bonded Silica-gel and its Application to Resolution

In order to set up a simple and effective method for resolution of optical isomers, hydroxypropyl-β-cyclodextrin was bonded to silica-gel, which can be used for preparation of thin-layer chromatography plates. Resolution of clenbuterol and propranolol were investigated on these thin-layer chromatography plates using different combinations of solvent systems at ambient temperature. The best simultaneous resolution was achieved in solvent system of acetonitrilen-butanol （50：50, v/v）. Rst values of resolution of clenbuterol hydrochloride and propranolol hydrochloride are 3.6 and 4.3, respectively. The spots of different enantiomers are separated clearly. The results showed that hydroxypropyl-β-cyclodextrin bonded silica-gel could be successful in resolution of chiral adrenergic drugs. The study offers a direct, rapid and reliable method for separation of this kind of optically active compounds.

Preparation and Evaluation of Insulin-loaded Nanoparticles based on Hydroxypropyl-β-cyclodextrin Modified Carboxymethyl Chitosan for Oral Delivery

Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan（CMC-HP-β-CD） were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterized by FT-IR spectroscopy and 1H-NMR spectra. The insulin-loaded nanoparticles were prepared through crosslinking with calcium ions, and the morphology and size of the prepared nanoparticles were characterized by transmission electron microscopy（TEM） and dynamic light scattering（DLS）. Cumulative release in vitro study was performed respectively in simulated gastric medium fluid（SGF, p H=1.2）, simulated intestinal fluid（SIF, p H=6.8） and simulated colonic fluid（SCF, p H=7.4）. The encapsulation efficiency of insulin was up to 87.14 ± 4.32% through high-performance liquid chromatography（HPLC）. Statistics indicated that only 15% of the encapsulated insulin was released from the CMC-HP-β-CD nanoparticles in 36 h in SGF, and about 50% of the insulin could be released from the nanoparticles in SIF, whereas more than 80% was released in SCF. In addition, the solution containing insulin nanoparticles could effectively reduce the blood glucose level of diabetic mice. The cytotoxicity test showed that the samples had no cytotoxicity. CMC-HP-β-CD nanoparticles are promising candidates as potential carriers in oral insulin delivery systems.

6-O-(Hydroxypropyltrimethylammonia)-β-cyclodextrin with Low Degree of Substitution: Convenient Preparation and its Application as a Chiral Selector in Capillary Electrophoresis

A cationic cyclodextrin derivative 6-O-（hydroxypropyltrimethylammonia）-β-cyclodextrin （GTA-β-CD） with low degree of substitution was prepared through a convenient method in solid phase. The product could be used as a valuable chiral selector in the capillary electrophoresis （CE） separation of some acidic drug enantiomers such as naproxen, ofloxacin, ibuprofen and warfarin.

Preparation of Forsythiaside-hydroxypropyl-β-cyclodextrin Inclusion Complex and Its Characters

To overcome the chemical instability of forsythiaside,the forsythiaside-hydroxypropyl-β-cyclodextrin inclusion complex was prepared by triturating. The inclusion complex was found having a varied UV spectrum and melt temperature point. Inclusion complex has a higher stability to UV light and temperature over forythiaside itself. Pharmacological evidence showed that inclusion complex has little effect on pharmacokinetics by chicken intravenous injection. This study is favorable for developing preparations for forsythiaside and its clinical application.

Solubility Enhancement of Domperidone Fast Disintegrating Tablet Using Hydroxypropyl-<i>β</i>-Cyclodextrin by Inclusion Complexation Technique

Domperidone Maleate (DOM), an antiemetic drug, has been used in treatment of adults and children. It has low aqueous solubility and hence low bioavailability. In present study, an attempt has been made to enhance the solubility of DOM by inclusion complexation with Hydroxypropyl-β-Cyclodextrin (HP-β-CD) using kneading technique and formulation of fast disintegrating tablets by using Sodium Starch Glycolate as superdisintegrant. Solubility analysis of DOM in different concentrations of HP-β-CD was carried out. Design of experiment (DOE) is done by using MINITAB 15.1 software to find out the variable for dissolution and disintegration time. HP-β-CD and SSG were identified as the variable for disintegration time and dissolution. For optimization of the concentration of HP-β-CD and SSG, two factors at two levels design through central composite design (CCD) were used which gave 13 formulations. All formulations are evaluated for characteristics such as weight variation, hardness, friability, disintegration time and dissolution of drug. Solubility of DOM increases linearly with increase in concentration of HP-β-CD. The optimum concentration of HP-β-CD is found to be in 1:2 molar ratios and SSG of 7%. The In-Vitro dissolution studies of optimized formulation and market sample were carried out in USP type II apparatus at different time intervals of 5, 10, 15 and 30 minutes at 50 rpm in 0.1 N HCl. The dissolution and disintegration time of optimized formulation is found better than market sample.

Preparation of waterborne polyurethane/β-cyclodextrin composite nanosponge by ion condensation method and its application in removing of dyes from wastewater

Currently,polymer nanosponges have received extensive attention.However,developing new synthetic techniques for novel nanosponges remains a challenge.Furthermore,to date,composite nanosponge adsorbents based on waterborne polyurethane(WPU)andβ-cyclodextrin(β-CD)have not been reported.Herein,a novel green method,ion condensation method,was developed in this study for the preparation of polymer nanosponge adsorbents for efficient removal of dyes from wastewater.Based on the principle of charge repulsion between nanoparticles to maintain emulsion stability,waterborne polyurethane/β-cyclodextrin composite nanosponges(WPU-x,y)were prepared by coagulating the emulsions synthesized from 2,2-dimethylolpropionic acid,polypropylene glycol and hexamethylene diisocyanate as raw materials in a mixture of hydrochloric acid and anhydrous ethanol.The structure and appearance of WPU-x,y were characterized by attenuated total reflectance Fourier transform infrared spectroscopy,thermal gravimetric analyzer,scanning electron microscope and mercury intrusion porosimetry.The adsorption capacity of WPU-x,y was tested by parameters such as cross-linking degree,β-CD dosage,contact time,initial dye concentration and p H value.The study found that WPU-4,4.62 had the best adsorption effect on methylene blue(MB),the maximum removal rate was 93.42%,and the maximum adsorption capacity was 136.03 mg·g^(-1).Moreover,the Sips isotherm and pseudo-second-order-model were suitable for MB adsorption.Therefore,this study provides some perspectives for the fabrication of nanosponge adsorbents.

Strong Inclusion Complexation Using Hydroxypropyl-β-Cyclodextrin as Host Molecule

Inclusion complexes of nitro-compounds using β-cyclodextrin and hydroxypropyl-β-cyclodextrin as host molecule have been studied by cyclic voltammetric method. The inclusion constants of the corresponding complexes have been determined. Strong inclusion complexation by hydroxypropyl-β-cyclodextrin has been verified

Preparation,Characterization and Antioxidant Activity of Inclusion Complex of Bakuchiol with Hydroxypropyl-β-cyclodextrin

Bakuchiol isolated from Psoralea corylifolia is a naturally occurring prenylated phenolic monoterpene with a variety of bioactivities.The aim of this study was to improve the water solubility and thermal stability of bakuchiol through complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The bakuchiol/HP-β-CD inclusion complex's behavior and characterization were investigated by ultraviolet-visible(UV-vis)spectroscopy,Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TGA),X-ray diffraction(XRD),1H nuclear magnetic resonance(NMR),and two-dimensional(2D)NMR.The obtained results indicated the formation of 1∶1 inclusion complex for bakuchiol with HP-β-CD.Water solubility of bakuchiol was significantly improved by complexation with HP-β-CD as demonstrated by phase solubility studies.The encapsulation of bakuchiol was confirmed by UV-vis,FT-IR,and XRD.The thermal stability was effectively enhanced by TGA and derivative thermogravimetry(DTG)analysis.In vitro antioxidant activity showed that bakuchiol/HP-β-CD inclusion complex had a little higher antioxidant ability than free bakuchiol.Moreover,we got the possible inclusion mode for the bakuchiol/HP-β-CD inclusion complex through NMR analysis.These results suggest that the inclusion complex can be a potentially useful approach in the design of novel formulations of bakuchiol for medical applications.

Preparation Process of Hydroxypropyl Tetrahydropyrantriol Liposomes

[Objectives] To explore the optimal process for preparing hydroxypropyl tetrahydropyrantriol liposomes. [Methods] A refractive index method was used to determine the content of hydroxypropyl tetrahydropyrantriol. Using particle size distribution and encapsulation rate as evaluation indicators, the effects of hydration time, ratio of organic phase to aqueous phase, granulation method, as well as thin film dispersion and reverse evaporation methods on liposomes preparation were investigated, and the optimal preparation method was selected. Single factor experiments were used to screen the drug phospholipid ratio, ultrasound time, and phospholipid cholesterol ratio, and the preparation process was optimized through orthogonal experiments. [Results] The optimal process of preparing hydroxypropyl tetrahydropyrantriol liposomes was as below: 1 : 10 of drug phospholipid ratio, 6 min of ultrasound time, 4 : 1 of phospholipid cholesterol ratio, (60.94%±7.24%) of entrapment efficiency, (86.44±6.08) nm of particle size, (0.195±0.077) of PDI. [Conclusions] The optimal preparation process of hydroxypropyl tetrahydropyrantriol liposomes selected by orthogonal experiment could effectively improve the encapsulation efficiency of hydroxypropyl tetrahydropyranotriol and reduce particle size. Moreover, the method was stable and reliable.

湿热处理对羟丙基淀粉结构特性及凝胶性能的影响

羟丙基淀粉制备的水凝胶与普通淀粉相比具有更好的拉伸性,但凝胶的力学性能较差。本文主要探究湿热处理对羟丙基淀粉物理和化学性质及凝胶性能的影响。湿热处理后,羟丙基淀粉的热稳定性与对照相比有所提高,焓值从12.55J/g降低至6.58J/g;从X-射线多晶衍射图谱(XRD)分析看出,湿热处理使羟丙基淀粉的结晶度从30.4%降至19.6%,说明湿热造成羟丙基淀粉内部双螺旋的解旋,结晶被破坏;羟丙基淀粉的峰值粘度先上升到5 000 cP左右,后下降到3 000cP左右;质构仪(TPA)和流变分析发现,湿热处理后,羟丙基淀粉凝胶的硬度从223.51g增至463.50 g,提高了储能模量,表明湿热处理提高了凝胶的机械性能。

基于淀粉微球交联剂的低浓度羟丙基胍胶压裂液性能研究

目的针对低渗透油藏,需要降低压裂液稠化剂用量,减少对储层的伤害,并确保压裂液具备延迟交联、携砂等性能和耐温耐剪切性能。方法利用反相乳液聚合法合成淀粉微球,通过硅配体和硼羟基修饰淀粉微球表面,制备了一种交联性能优良、伤害性低的微球型硅硼交联剂(KBSM)。结果KBSM交联剂能够实现多活性位点交联,增强交联密度,从而降低羟丙基胍胶(HPG)的用量,具有延迟交联特性。其延迟交联时间在2~6 min内可调。质量分数为0.2%的HPG交联冻胶在120℃、170 s-1剪切120 min后的黏度为80 mPa·s。交联冻胶中砂质量分数(以下简称携砂比)为40%时,陶粒沉降速度为0.1167 cm/min。加入质量分数为0.25%的过硫酸铵破胶剂可使交联冻胶在90℃下、120 min内完全破胶,且残渣质量浓度为214 mg/L。同时,破胶液的岩心损害率为26.55%。结论基于淀粉微球交联剂的低含量羟丙基胍胶压裂液对于降低低渗储层伤害有一定的指导意义。

丝素蛋白联合壳聚糖基热敏水凝胶的性能评估

目的在壳聚糖(CS)/羟丙基甲基纤维素(HPMC)热敏水凝胶的基础上,利用丝素蛋白(SF)与CS交联,构建CS/HPMC/SF水凝胶,研究SF对水凝胶的性能影响。方法共混法制备CS/HPMC混合溶液,向其中分别添加1%、5%、10%的SF溶液及交联剂京尼平,加入圆柱形模具中,升温至37℃,使溶液转为凝胶态。对水凝胶进行形貌、傅里叶变换红外光谱仪(FTIR)、X射线衍射(XRD)以及亲水性及力学性能表征检测。结果扫描电子显微镜下观察水凝胶为多孔状,随着SF的加入,孔隙减少,出现裂痕。FTIR和XRD结果显示,CS与HPMC混合后结晶程度改变,当加入SF后,SF与CS发生化学交联,结构发生转变,水凝胶的亲水性也因此减弱。力学表征显示,当SF的添加量为5%时,水凝胶的回弹性最优,弹性模量最大,且基本保持不变。结论SF与CS的交联改进了CS基热敏水凝胶的性能,相比于其他组水凝胶,CS/HPMC-5%SF保持良好的亲水性且具有较好的力学性能。

药用辅料羟丙基甲基纤维素的细胞毒性研究

目的采用MTT比色法进行羟丙基甲基纤维素(HPMC)体外细胞毒性试验,以评价HPMC作为药用辅料的生物安全性。方法将L929细胞分为空白对照组(只加细胞培养液)、HPMC组(K4M、K100M两种规格,浓度分别为10.0、5.0、1.0、0.5、0.1 mg/ml)。置于培养箱中培养24、48 h,用MTT方法测定490 nm处的吸光度值,计算细胞毒性试验中细胞相对增殖率(RGR)。结果不同规格(K4M、K100M)、不同浓度(10.0、5.0、1.0、0.5、0.1 mg/ml)HPMC的平均细胞RGR>85%,属于无细胞毒性。结论研究结果证实HPMC对L929细胞无细胞毒性,这说明HPMC的细胞毒性达到国家标准对生物材料细胞毒性所限定的要求,为安全的药用辅料。

一种壳聚糖改性产物的制备工艺及其产品吸附性能的研究

以壳聚糖(CTS)为母体,加入冰醋酸溶解得到CTS溶液,以无水乙醇为致孔剂,制备多孔壳聚糖微球,将制得的CTS微球与环氧氯丙烷(ECH)交联,制备出羟丙基壳聚糖微球(HPCTS),对产物进行红外光谱和电镜扫描性能表征。通过红外光谱图分析可以看出,ECH与CTS进行了交联反应。比较CTS和HPCTS的电镜扫描图片,发现HPCTS表面因为交联反应而形成大量多孔结构,增加了大量可供吸附重金属离子的空穴,使得HPCTS比交联前的表面积有了大幅提高。通过单因素实验,研究了制备HPCTS的工艺参数,在较优工艺参数下制备的产物交联度可达75.23%,产品具有良好的可再生性。

羟丙基-β-环糊精-姜黄素包合物的制备及其光动力杀灭沙门氏菌的机制

沙门氏菌是国内外引起人类食源性疾病最主要的食源性致病菌之一,开发新型有效的抗菌技术对保障食品安全至关重要。本研究利用羟丙基-β-环糊精(HP-β-CD)的包合作用,包合姜黄素(Curcumin,CUR)作为光敏剂,研究其介导光动力技术(Photodynamic Inactivation Technology,PDI)对食品样品中鼠伤寒沙门氏菌ATCC14028的杀菌效果及作用机制。设置乙醇浓度为40%、HP-β-CD与CUR摩尔比为2:1,在45℃条件下包合4 h时,所形成的CUR包合率最大,为60.08%,该包合物经结构表征后测定其水溶性显著(P<0.05)提高,达到3.98×10^(3)μg/mL。结果表明,当包合物质量浓度(以CUR浓度计)为20µg/mL,初始鼠伤寒沙门氏菌菌落数量级为106 CFU/mL时,LED蓝光(450 nm)照射40 min可使菌落数减少3.73 lg(CFU/mL),可杀灭47.92%~64.40%的耐药沙门氏菌,并且对即食生菜中的沙门氏菌也有一定的控制作用。在光动力技术处理后,沙门氏菌胞内产生了较高水平的活性氧,胞内容物明显减少,推测CUR-HP-β-CD介导的PDI可能通过破坏细胞膜结构达到杀菌抑菌的目的。本研究将光动力杀菌技术应用于食品安全领域,这为食品工业中防治沙门氏菌等食源性致病菌的污染提供了重要的理论基础和技术支撑。