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.

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.

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.

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.

HPCD对甲基对硫磷的增溶、洗脱与光降解

研究了一种高水溶性的环糊精衍生物羟丙基-β-环糊精(HPCD)溶液对甲基对硫磷的增溶作用、土壤中甲基对硫磷的洗脱去除作用以及对甲基对硫磷的光降解作用.结果表明,HPCD 使甲基对硫磷在水中的溶解度显著增加,20g/L 的 HPCD 溶液中,甲基对硫磷的溶解度比在纯水中提高了约 13 倍;HPCD 溶液能有效地对土壤中的甲基对硫磷进行洗脱,10g/L 的 HPCD 溶液洗脱率为 90%以上;HPCD 能促进甲基对硫磷的光降解,6g/L 的 HPCD 使甲基对硫磷的半衰期(T1/2)由原来的 103.90h 减少到 15.16h,而且表现出很高的光敏效应,光敏效率为 90.3%.结合其高增溶能力、高洗脱能力与光催化降解能力,HPCD 能有效地降低弱极性有机污染物在环境中的污染.

Synthesis of Atrazine-HPCD Inclusion and Its Bioactivity

The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion were also studied here. The results indicated that the UV maximum absorption wavelength of the inclusion remained at 223 nm, while its intensity decreased. The XRD peaks of atrazine disappeared, weakened and shifted in the inclusion, and the chemical shift of H-3 and H-5 of cyclodextrin inner cavity led to the upfield. The characterization data showed that the atrazine-HPCD inclusion had already formed. At the same time, the solubility of the atrazineHPCD inclusion in water became 20.08 times as that of atrazine. Moreover, the atrazine-HPCD inclusion had better herbicidal activity. When the concentration of the inclusion was 6.5 mg/mL, the inhibition ratios of the inclusion to taproot length, taproot fresh weight, sprout length and sprout fresh weight of barnyard grass were 66.96%, 57.22%, 70% and 57.53%, respectively, which were all higher than those of atrazine.

Water-Based Environmentally Friendly Pesticide Formulations Based on Cyclodextrin/Pesticide Loading System

Difenoconazole(DIF)is a representative variety of broad-spectrum triazole fungicides and liposoluble pesticides.However,the water solubility of DIF is so poor that its application is limited in plant protection.In addition,the conventional formulations of DIF always contain abundant organic solvents,which may cause pollution of the environment.In this study,two DIF/cyclodextrins(CDs)inclusion complexes(ICs)were successfully prepared,which were DIF/β-CD IC and DIF/hydroxypropyl-β-CD IC(DIF/HP-β-CD IC).The effect of cyclodextrins on the water solubility and the antifungal effect of liposoluble DIF pesticide were investigated.According to the phase solubility test,the molar ratio and apparent stability constant of ICs were obtained.Fourier transform infrared spectroscopy,thermal gravity analysis,X-ray diffraction and scanning electron microscopy were used systematically to characterize the formation and characteristics of ICs.The results noted that DIF successfully entered the cavities of two CDs.In addition,the antifungal effect test proved the better performance of DIF/HP-β-CD IC,which exceeded that of DIF emulsifiable concentrate.Therefore,our study provides informative direction for the intelligent use of liposoluble pesticides with cyclodextrins to develop water-based environmentally friendly formulations.

Impact of solids on biphasic biodegradation of phenanthrene in the presence of hydroxypropyl-β-cyclodextrin(HPCD)

The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great concern.The hydrophobic properties of PAHs significantly impact phase distribution causing limited bioavailability.Enhanced biodegradation has been extensively carried out by surfactants and the redeployment effect was recognized.However,the quantitative relationship concerning the impact of solids was rarely reported.A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin(HPCD)into a mixture of phenanthrene solution and various glass beads(GB37-63,GB105-125,and GB350-500).The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.A model was proposed to describe the biodegradation process.The regression results indicated that the partition coefficient kd(1.234,0.726 and 0.448 L·g–1)and the degradation rate k(0 mmol·L^(–1):0.055,0.094,and 0.112;20 mmol·L^(–1):0.126,0.141,and 0.156;40 mmol·L^(–1):0.141,0.156 and 0.184 d^(–1))were positively and negatively correlated with the calculated total surface area(TSA)of solids,respectively.Degradation enhanced in the presence of HPCD,and the enhancing factor f was calculated(20 mmol·L^(–1):15.16,40.01,and 145.5;40 mmol·L^(–1):13.29,37.97,and 138.4),indicating that the impact of solids was significant for the enhancement of biodegradation.

固定化毛霉对工业和农田污染土壤中多环芳烃的降解和生物有效性评价

为了探讨微生物修复不同类型多环芳烃污染土壤的可行性,应用固定化毛霉对多环芳烃污染工业土壤及农田土壤进行微生物修复,用羟丙基-β-环糊精(HPCD)提取模拟评价多环芳烃的微生物可利用性,并分析多环芳烃微生物降解和生物可利用性的相关关系.焦化厂污染土壤中多环芳烃的30 d降解率为77.6%,沈抚灌区污染土壤中多环芳烃的30 d降解率为54.2%,焦化厂土壤和污灌区农田土壤中多环芳烃降解差异明显.焦化厂土壤和污灌区土壤中多环芳烃的30 d降解量和多环芳烃的环糊精可提取量具有相关性,各环数多环芳烃的环糊精可提取量变化解释了焦化厂和污灌区土壤中多环芳烃降解的差异机制,说明可用环糊精提取量预测微生物降解土壤多环芳烃的情况.

Preparation and Physicochemical Characterization of Quercetin-HP-β-CD Inclusion Complexes

Aim To prepare and characterize the QURC-HP-β-CD inclusion complexes and investigate the thermodynamic parameters of the process. Methods QURC-HP-β-CD inclusion complexes were prepared by the grinding method. The equilibrium inclusion constants and thermodynamic parameters were determinated by phase solubility analysis. Dissolution tests were performed to study the dissolution rate of inclusion complexes. The formation of inclusion complexes was confirmed by differential scanning calorimetry （ DSC）, infrared spectroscopy （IR） , powder X-ray diffractometry （PXRD） and scanning electron microscopy （SEM）. Results The aqueous solubility of quercetin was greatly increased （ about 37 folds） by inclusion technique, and the initial dissolution rate was markedly improved （10 folds） in the first 5 min. The results of DSC and SEM photographs showed that quercetin crystal disappeared in inclusion complexes, which indicated the formation of new phase. FT-IR spectra showed that the carbonyl quercetin crystal grinding method. absorption band of quercetin was shifted. PXRD showed that the diffraction peak of disappeared. Conclusion QURC-HP-β-CD inclusion complexes are produced by the The solubility of quercetin is improved by the inclusion technique.

Pharmacokinetics of Eb and its hydroxypropyl-β-cyclodextrin inclusion complex in rats

In our previous study,a novel organic selenium compound Eb was synthesized and found to have significant antitumor activity with much less toxicity compared with the leading compound Ebselen.Unfortunately,Eb was practically insoluble in water （2.57 μg/mL） and had very low oral bioavailability,thus its clinical application was greatly limited.In the present study,the inclusion complex of Eb with 2-hydroxypropyl-β-cyclodextrin （HP-βCD） was prepared and pharmacokinetics of Eb and the inclusion complex were investigated.The water solubility of Eb was dramatically enhanced by inclusion with HP-βCD,which reached 8.4 mg/mL.The pharmacokinetic study showed that the elimination half-life （t 1/2β） of Eb was between 22 h and 30 h and the distribution half-life （t 1/2α） of Eb was 1 h.The results indicated that Eb was rapidly distributed to tissues but slowly eliminated in rats.The absolute bioavailability of Eb/HP-βCD inclusion complex solution through the oral route was 28.3%,and it was 1552% that of Eb in its pure form.In summary,the absorption of Eb in the Eb/HP-βCD inclusion complex was better and faster than that of Eb in its pure form.

羟丙基-β-环糊精对地高辛透过大鼠小肠黏膜的影响

目的考察在不同质量浓度羟丙基-β-环糊精(hydroxypropyl-β-cyclodextrin,HPCD)溶液中地高辛透过大鼠小肠黏膜的能力。方法用大鼠离体外翻肠囊法进行小肠透过量试验;用HPLC法检查肠液中药物质量浓度。结果当HPCD质量浓度为0、1、2、5、10 mg.L-1时,地高辛2 h内在小肠中的累积吸收百分率依次降低,分别为51.3%、42.8%、33.1%、32.6%、11.7%。结论HPCD包合物降低了地高辛的小肠透过量,并减慢其吸收速度;游离药物与被包合药物存在着快速平衡,仍有部分药物透过小肠黏膜吸收。

肉桂精油纳米乳液的抑菌性和稳定性研究

为改善精油的稳定性及抑菌性能,利用羟丙基-β-环糊精(HPCD)与酪蛋白酸钠(SC)共同乳化肉桂精油(CEO)制备纳米乳液,探究乳液的粒径、抑菌性的变化及乳液在不同温度下的储存稳定性。结果表明,相比单独使用酪蛋白酸钠稳定的乳液,HPCD的添加可以显著降低酪蛋白酸钠-精油乳液的粒径及PDI值。1%酪蛋白酸钠和3%HPCD共同稳定的肉桂精油纳米乳液对大肠杆菌和金黄色葡萄球菌的生长有良好的抑制作用,当精油添加量为10%时,大肠杆菌浓度降低了2.62 lg(CFU/mL),金黄色葡萄球菌浓度降低了0.85 lg(CFU/mL);乳液在4、25、40℃下储存过程中的粒径、乳化指数的变化表明,1%酪蛋白酸钠和3%HPCD共同乳化的肉桂精油纳米乳液具备良好的稳定性。当精油体积分数为10%时,乳液的粒径、乳化指数随着储藏时间的延长有所增加,但荧光显微镜显示乳液中油滴仍然分布相对均匀。

Preparation of Hydroxypropyl-β-cyclodextrin Cross-linked Multi-walled Carbon Nanotubes and Their Application in Enantioseparation of Clenbuterol

A method of cross-linking multi-walled carbon nanotubes by a nucleophilic substitution of brominated multi-walled carbon nanotubes using hydroxypropyl-β-cyclodextrin anions was studied. The modified multi-walled carbon nanotube samples were characterized using thermogravimetric analysis, energy-dispersive X-ray spectroscopy, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The hydroxypropyl-β-cyclodextrin modified multi-walled carbon nanotubes were used as a chiral stationary phase additive for thin-layer chromatography to separate clenbuterol enantiomers, and the chiral separation factor was increased.

Physicochemical Properties and Gastric Mucosa Irritation of Cantharidin-hydroxypropyl-β-cyclodextrin Inclusion Complex

Objective To increase the solubility and relieve the mucous irritation of cantharidin (CA) by preparing cantharidin-hydroxypropyl-β-cyclodextrin (CA/HP-β-CD) inclusion complex. Methods The inclusion complex was prepared by co-evaporation method and characterized by differential scanning calorimetry (DSC), X-ray diffractometry (XRD), and nuclear magnetic resonance (NMR). Results The disappearance of CA as well as the shift of exothermic peaks shown in DSC results indicated the complexation phenomenon. XRD results showed that the crystalline CA pattern had disappeared, and in NMR results, H-5 shifted from δ 3.731 to 3.695 after complexation and H-2 shifted from δ 3.626 to 3.598, which suggested that part of the drug had entered the HP-β-CD cavity to form an inclusion complex. The solubility increased 10.3 times after complexation and the mucous irritation of CA was relieved remarkably. Conclusion Through complexation with HP-β-CD, the solubility and dissolution rate of CA are improved significantly, and the irritation of musous is relieved.

Multicomponent cyclodextrin system for improvement of solubility and dissolution rate of poorly water soluble drug

The purpose of the present study was to investigate the interaction of Cinnarizine(CIN)with Hydroxypropyl-β-Cyclodextrin(HPβCD)in the presence of Hydroxy Acids(HA).Various binary and ternary systems of CIN with HPβCD and HA were prepared by kneading and coevaporation methods.For the ternary systems,HA were tried in three different concentrations.The interaction in solution phase was studied in detail by the phase solubility method,and the solid phase interactions were characterized by Fourier Transform Infrared(FTIR)spectroscopy,Differential Scanning Calorimetry(DSC),X-Ray Diffractometry(XRD),Scanning Electron Microscopy(SEM)and Proton Nuclear Magnetic Resonance(^1H-NMR).Phase solubility revealed the positive effect of HA on the complexation of CIN with HPβCD.Solid phase characterization confirmed the formation of inclusion complex in the ternary systems.Solubility and dissolution studies illustrated that out of three different concentrations tried,HA were most effective at the 1 M concentration level.Ternary systems were very effective in improving the solubility as well as dissolution profile of CIN than the CIN–HPβCD binary systems.FTIR,^1H-NMR and Molecular docking studies gave some insight at molecular level that actually which part of CIN was interacting with the HPβCD.Molecular docking and free energy calculation even enlighten the role of tartaric acid in increasing solubility of CIN in the ternary system.

Enantiomeric separation of phenylsuccinic acid by cyclodextrin-modified reversed phase high-performance liquid chromatography

The chiral separation of phenylsuccinic acid(PSA)was studied by reversed phase high-performance liquid chromatography(RP-HPLC)with cyclodextrins(CDs)as chiral mobile phase additives.The effects of types of CDs,concentration of hydroxypropyl-β-cyclodextrin(HP-β-CD),percentage of organic modifier,pH value and column temperature on enantioselective separation were investigated.The quantification property of the developed RP-HPLC method was examined.The chiral recognition mechanism of PSA was also discussed.The results show that a baseline separation of PSA enantiomers is achieved on a Lichrospher C18 column(4.6 mm(inner diameter)×250 mm,5μm)with HP-β-CD as chiral mobile phase additive.The capacity factors of R-PSA and S-PSA are 3.94 and 4.80,respectively.The separation factor and resolution are respectively 1.22 and 8.03.The mobile phase is a mixture of acetonitrile and deionized water(20-80,volume ratio)containing 10 mmol/L HP-β-CD and 0.05% trifluoroacetic acid(pH 2.5,adjusted with triethylamine)with a flow rate of 1.0 mL/min.The ultraviolet(UV)detector is set at 254 nm.The likely roles are inclusion interaction,induction and hydrogen bonding between HP-β-CD and PSA enantiomers.

The efficacy of topical spray containing Centella asiatica extract on excision wound healing in rats

Centella asiatica (Linn.) belongs to the family of Apiaceae(Umbeliferae). It has been widely used for traditional medicine, especially for wound healing, anti-inflammatory,antipsoriatic, antiulcer, antibacterial and antifungal. The biologically active ingredients of Centella asiatica are believed to be triterpenes, particularly asiatic acid, madecassic acid,asiaticoside and madecassoside (Fig. 1).