Cyclodextrin and TIF4 nanocomplex on enamel demineralization

Abstract The aim of this study was to assess the effect of a newly developed nanocomplex formed of hydroxypropyl-b-cyclodextrin and 1% titanium tetrafluoride (TiF4) after distinct complexation periods (12/72 h) on demineralization of bovine enamel in vitro. Enamel blocks (n=60) were allocated in different groups: Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4, hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h of complexation and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation. The samples were evaluated by surface microhardness, cross-sectional microhardness and micro-CT. Scanning electron microscopy and energy dispersive X-ray spectrometry (SEM/EDX) were also obtained. Hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h complexation resulted in lower percentage of surface microhardness loss compared to Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4 and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation group, with a large effect size (from 1.307 to 2.943) and high power (84.9 to 99%). All groups resulted in similar integrated mineral loss (ΔZ) obtained by both internal microhardness and micro-CT techniques. Enamel treated with TiF4 and TiF4 + hydroxypropyl-b-cyclodextrin groups showed a TiO2 glaze-layer, while EDX evaluation identified Ti. The solution containing the inclusion complex of hydroxypropyl-b-cyclodextrin + TiF4 with 12 h of complexation period demonstrated a significant ability to reduce surface demineralization of sound enamel under an artificial cariogenic challenge.

Resumo O objetivo deste estudo foi avaliar o efeito da 1-etil-3- (3-dimetilaminopropil) carbodiimida (EDC) na resistência de união de pinos de fibra de vidro em canais radiculares obturados com diferentes cimentos endodônticos. Setenta e oito pré-molares inferiores foram obturados com três cimentos endodônticos (n=26): Endofill (END), AH Plus (AHP) e Endosequence BC Sealer (EBS). Após o preparo do espaço para pino, dois subgrupos formaram-se conforme a cimentação dos pinos (n=13): com EDC e sem EDC (controle - CON). Os espécimes foram submetidos ao teste pull-out, classificação do modo de falha e avaliação da superfície do canal radicular por microscopia eletrônica de varredura após o deslocamento. Quanto à força de resistência de união, uma diferença estatisticamente significativa ocorreu entre os subgrupos EDC e CON apenas no END (p=0,001). Não foi detectada diferença entre os subgrupos CON (p=0,339). Contudo, no subgrupo EDC, o AHP apresentou maiores valores (END versus AHP: p=0,001; AHP versus EBS: p=0,016). Acerca da classificação dos modos de falha, o escore 1 (≥50% de cimento) foi o mais comumente observado, exceto para END + EDC. Restos de cimentos endodônticos e cimentos resinosos foram encontrados no terço cervical, mas sem diferença estatística (p=0,269), enquanto no terço médio, houve diferença (p=0,004). Em conclusão, o EDC diminui a resistência de união quando associado ao cimento END, sem alterar o modo de falha entre o cimento resinoso e o pino de fibra de vidro. O melhor desempenho foi observado quanto o EDC foi usado com o cimento AHP.

Non-clinical study of the anxiolytic effect of Citrus aurantium L. essential oil in an inclusion complex with 2-hydroxypropyl-ß-cyclodextrin

Anxiety in the world population has increased significantly; the problem has encouraged studies regarding innovative alternatives for treatment. Research with Citrus aurantium L. essential oil (CEO) has revealed positive results with anxiolytic effects in both animals and humans. However, certain limitations affect its storage and preservation, its efficiency in therapy, and determination of adequate posologies. The potential use of cyclodextrins as drug carriers has been successfully explored. This study aims to assess the anxiolytic potential of a CEO/2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) inclusion complex. Preparation of the inclusion complex was performed using the Alpha 1-2 LDplus lyophilizer. To allow formation, and avoid loss of volatiles to the atmosphere, Limonene (LIM), the main compound in CEO, together with HP-ß-CD in a molar ratio of (1: 1M) was dispersed in ethanol for 36 hours using a laboratory shaker at room temperature (25°C). Non-clinical murine pharmacological tests were performed for anxiety assessment in experimental and control groups. To assess anxiety and motor impairment, the animals were evaluated using the elevated plus maze, open field, and rota-rod tests. Satisfactory results of the anxiolytic effect of the OEC complexed in HP-ß-CD were observed, with the indication of an potentiation of the effect with doses lower than 500 mg/kg and 250 mg/kg complexed, suggesting improvement in the anxiolytic properties of the OEC.

Inclusion complexes of atorvastatin calcium–sulfobutyl ether β cyclodextrin with enhanced hypolipidemic activity

The aim of present study was to explore the impact of Atorvastatin (ATR) Sulfobutylether beta-cyclodextrin complex(ATR-SBE-β-CD) on ATR dissolution behavior. Various batches of inclusion complexes were formulated usingvarious drug: polymer ratios (1:1, 1:3, and 1:5); using β-CD and SBE-β-CD and using two methods (freeze dryingand kneading method). Phase solubility studies were carried out of all the complexes and ratio 1:5 (ATR-SBE-β-CD)prepared by freeze-drying yield maximum solubility enhancement (30-fold in comparison to pure drug). Fouriertransformation infrared spectroscopy, Powder X-ray diffraction, Scanning electron microscopy (SEM), Differentialscanning calorimetry (DSC) studies was also carried out. FTIR studies showed no drug polymer interaction. DSCand SEM studies suggested incorporation of drug into inclusion complexes of cyclodextrin. Solid dispersion viaFreeze drying technique using SBE-β-CD (1:3 ratio of drug to polymer) produces better dissolution characteristics incomparison to kneading method. The results revealed superiority of SBE-β-CD over β-CD for solubility enhancementof poorly soluble drugs (owing to amorphous nature and more stable form of SBE β-CD). No significant drug losswas observed in solid dispersion batch (as per results of drug content analysis) during storage for 3 months underaccelerated conditions. Further in vivo pharmacodynamics studies of selected batch were carried out by inducingobesity in rats by feeding them with a high-fat diet. Group I (normal control group) received normal chow diet andgroup II, group III, group IV (High fat diet group, optimized formulation group and disease control group) receivedHFD for 1 month and were further evaluated for BMI, Blood glucose, lipid profile, liver profile, and histopathologicalexamination. The results so obtained depicted that optimized formulation of Atorvastatin (10 mg/kg, p.o.) showedbetter results in comparison to pure Atorvastatin Calcium (10 mg/kg, p.o.).

Nano-Sponge Novel Drug Delivery System As Carrier Of Anti-Hypertensive Drug

Objective: The study was designed to prepare Nano-sponge formulation loaded with nifedipine. Studying parameters which affecting the formulas in addition to pharmacokinetics and toxicity tests. Methods: Nine Nano-sponge formulations were prepared by the solvent evaporation technique. Different ratios of polymer ethylcellulose, CO-polymers β-cyclodextrin and hydroxypropyl β-cyclodextrin in addition to solubilizing agent polyvinyl alcohol were used. Thermal analysis, X-ray powder diffraction (XRPD), shape and surface morphology, particle size, %production yield, %porosity, % swelling, and % drug entrapment efficiency of Nano-sponge were examined. Release kinetic also studied beside comparison of pharmacokinetic parameters of the optimum choice formula and marketed one in addition to Toxicological consideration. Results: Particle size in the range of 119.1 nm to 529 nm which were increased due to the increase in the concentration of polymer to the drug. Nano-sponge revealed porous, spherical nature. Increased in the drug/polymer molar ratios (1:1 to 1:3) may increase their % production yield ranged from 62.1% to 92.4%. The drug content of different formulations was in the range of 77.9% to 94.7%, and entrapment efficiency was in the range of 82.72 % to 96.63%. Drug released in controlled sustained pattern and followed Higuchi, s diffusion mechanism. Pharmacokinetic parameters of optimized formula showed significant higher maximum plasma drug concentration, area under plasma concentration-time curve, volume of distribution and mean residence time. Nano-sponge loaded drug proved biological safety at low concentrations. Conclusion: Nano-sponge drug delivery system has showed small Nano size, porous with controlled drug release and significant-high plasma drug concentration that improved solubility, drug bioavailability and proved safety.

comparative study of dissolution profile of drug by enhancing aqueous solubility through Kneading method

Solid dispersions (SDs) are resulted by dispersion of drug in biologically inert matrix. They can be used to increase the solubility of a drug with low aqueous solubility, thereby improving its oral bioavailability. Higher drug dissolution rates from a SD can be facilitated by optimizing the wetting characteristics of the compound surface, as well as increasing the interfacial area available for drug dissolution. Although the latter can be easily accomplished by, for example: decreasing the particle size of the drug powder but micronized powders may result in further complications as they occasionally tend to agglomerate. A more preferable solution would be to introduce the drug in the form of a molecular dispersion. The aim of present study was to enhance the dissolution rate of diclofenac a practically less water-soluble drug. The same was done by preparation of solid dispersions of the drug employing different ratios of established polymers. This was done by using polymers namely; hydrophilic polymer β-cyclodextrins, PVP and PEG. The kneading method was used to prepare solid dispersions in various ratios with polymer. The dissolution data was studied for all the three formulations. The data obtained was compared with that of physical mixtures containing drug, polymer and lactose in the same ratio as that of solid dispersions. The dissolution data showed that best release was obtained in formulation f1 containing beta –cyclodextrins, PVP and PEG as polymer. The comparative data showed 98% release at approximately 4 hours with polymer β –cyclodextrins, whereas, 90% and 88% release were obtained using PEG and PVP respectively in the same time frame.

Inclusion complexes and self-assembled cyclodextrin aggregates for increasing the solubility of benzimidazoles

Albendazole and fenbendazole are imidazole derivatives that exhibit broad spectrum activity against parasites, but the low solubility of these drugs considerably reduces their effectiveness. Complexation of albendazole and fenbendazole with cyclodextrins (ß-cyclodextrin and hydroxypropyl-ß-cyclodextrin) in both water and an aqueous solution of polyvinylpyrrolidone (PVP-k30) was studied to determine if it could increase the solubility and dissolution rate of the drugs. In an aqueous solution, ß-cyclodextrin increased the solubility of albendazole from 0.4188 to ~93.47 µg mL-1 (223×), and of fenbendazole from 0.1054 to 45.56 µg mL-1 (432×); hydroxypropyl-ß-cyclodextrin, on the other hand, increased solubility to ~443.06 µg mL-1 (1058×) for albendazole and ~159.36 µg mL-1 (1512×) for fenbendazole. The combination of hydroxypropyl-ß-cyclodextrin and polyvinylpyrrolidone enabled a solubility increase of 1412× (~591.22 µg mL-1) for albendazole and 1373× (~144.66 µg mL-1) for fenbendazole. The dissolution rate of the drugs was significantly increased in binary and ternary systems, with hydroxypropyl-ß-cyclodextrin proving to be more effective. The presence of the water-soluble PVP-k30 increased the dissolution rate and amorphization of the complexes. Analysis of the changes in displacement and the profile of the cyclodextrin bands in the 1H NMR spectra revealed a molecular interaction and pointed to an effective complexation in the drug/cyclodextrin systems. Monomeric forms and nanoclusters of cyclodextrins were observed in the drug/cyclodextrin systems, suggesting that the increase in solubility of the drugs in the presence of cyclodextrins should not be attributed only to the formation of inclusion complexes, but also to the formation of cyclodextrin aggregates

Orthogonal experimental study on preparation technology of borneol-β-CD inclusion complex / 国际中医中药杂志

Objective To study the optimal preparation of β-cyclodextrin inclusion borneol by saturated aqueous solution. Methods The orthogonal experimental design was used to evaluate the inclusion process using the content of borneol in the inclusion complex as an indicator. Results The optimum inclusion compound technology was β-CD 20 g, the amount of borneol was 2.3 g, the water temperature was 65 ℃, and the stirring speed was 800 r/min. Conclusions This process is simple, stable, and high in inclusion rate. It is suitable for scientific research and industrial application.

Complexation and enhancement of temozolomide solubility with cyclodextrins

ABSTRACT Temozolomide is a poorly soluble anti-cancer drug used in the treatment of some brain cancers. Following literature reports about the enhancement of solubility and stability for these kinds of drugs upon complexation with cyclodextrins, we aimed to form an inclusion complex between temozolomide and the different types of cyclodextrins (CDs) to enhance its solubility. In this study, three different cyclodextrins (ß -CD, hydroxyl-ß-CD and γ-CD) were used, and changes in solubility was measured by UV-Vis Spectroscopy and HPLC. Morphological changes upon complexation were shown by the Scanning Electron Microscope (SEM), and weight loss profiles with respect to temperatures which were unique to the compounds were shown by Thermogravimetric Analysis. Changes in heat release profiles were shown by Differential Scanning Calorimeter (DSC). Drug solubility was measured to be increased to around 25% for 1:1 molar ratio for all used CD complexations. Changes of morphology, heat release and weight loss profiles are consistent with the formation of an inclusion complex between CDs and temozolomide. In this study, success was shown in the enhancement of temozolomide solubility upon complexation with different types of CDs. It has been demonstrated that cyclodextrins can be used as complexing agents for poorly soluble anti-cancer drugs, increasing their solubility and hence drug availability

Study on Inclusion Behavior of Carbendazim with Cyclodextrins / 分析化学

Hydrophobic medicine carbendazim,come into inclusion compounds with β-cyclodextrin(β-CD),2-hydroxypropyl-β-CD (2-Hp-β-CD) and 2,6-dimethyl-β-CD(Me-β-CD),were made by solvent method.By investigating the inclusion behaviors of these three cyclodextrins combined with carbendazim using 1H NMR,2D rotating frame overhause effect spectroscopy (ROESY) and diffusion ordered spectroscopy,the possible ways of combinations and the recognition ratio of this three inclusion compounds,Dβ-CD=2.516×10-10m2/s,D2-Hp-β-CD=1.676×10-10m2/s,DMe-β-CD=2.046×10-10m2/s,were obtained.According to X-ray power diffraction,thermogravimetric analysis,infrared spectroscopy and scanning electron spectroscopy characterization,it was found that the characteristic diffraction peaks changed after carbendazim and cyclodextrin formed into inclusion compounds,and the characteristic diffraction peak of carbendazim at 10.4°,21.2°,25.8°,31.5°(2θ) lost or disappear.The pyrolysis temperature of carbendazim was 197.5℃,and would be higher than 260℃ after it formed inclusion complex.The infrared spectrum also showed that the oscillation peaks of inner cyclodextrin cavum apparently reduced after carbendazim combined,which demonstrated that the position of water molecules inside cyclodextrin cavum were occupied by the carbendazim molecules.With the help of SEM,the appearances of inclusion were different from a single carbendazim molecule,which manifested a new structure appeared.

Sugammadex ED90 dose to reverse the rocuronium neuromuscular blockade in obese patients / Dose ED90 de Sugamadex para reverter o bloqueio neuromuscular com rocurônio em pacientes obesos

ABSTRACT Objective: to determine the ED90 (minimum effective dose in 90% of patients) of sugammadex for the reversal of rocuronium-induced moderate neuromuscular blockade (NMB) in patients with grade III obesity undergoing bariatric surgery. Methods: we conducted a prospective study with the biased coin up-and-down sequential design. We chosen the following doses: 2.0mg/Kg, 2.2mg/Kg, 2.4mg/Kg, 2.6mg/Kg, 2.8mg/Kg. The complete reversal of rocuronium-induced NMB considered a T4/T1 ratio ≥0.9 as measured by TOF. After induction of general anesthesia and calibration of the peripheral nerve stimulator and accelerometer, we injected rocuronium 0.6mg/kg. We administered propofol and remifentanil by continuous infusion, and intermittent boluses of rocuronium throughout the procedure. Results: we evaluated 31 patients, of whom 26 had displayed successful reversal of the NMB with sugammadex, and failure in five. The mean time to complete moderate NMB reversal was 213 seconds (172-300, median 25-75%). The ED90 of sugammadex calculated by regression was 2.39mg/kg, with a 95% confidence interval of 2.27-2.46 mg/kg. Conclusion: the ED90 of sugammadex in patients with grade III obesity or higher was 2.39mg/kg.

RESUMO Objetivos: determinar a ED90 (dose mínima eficaz em 90% dos pacientes) de sugamadex para a reversão de bloqueio neuromuscular (BNM) moderado induzido pelo rocurônio em pacientes com obesidade grau III submetidos à cirurgia bariátrica. Métodos: estudo prospectivo com o método de projeção sequencial para cima e para baixo da moeda enviesada. As seguintes doses foram escolhidas: 2,0mg/kg-1, 2,2mg/kg-1, 2,4mg/kg-1, 2,6mg/kg-1, 2,8mg/kg-1. A reversão completa de BNM induzido por rocurônio considerou uma relação T4/T1 ≥0,9 na medida do TOF. Após a indução da anestesia geral e calibração do estimulador de nervo periférico e acelerômetro, rocurônio 0,6mg/kg-1 foi injetado. Infusão contínua de propofol e remifentanil, e bolus intermitente de rocurônio foram injetados durante todo o procedimento. Resultados: trinta e um pacientes foram avaliados, 26 dos quais bem-sucedidos e cinco sem reversão completa do BNM moderado promovido pelo sugamadex. O tempo médio para completar reversão de BNM foi 213 segundos (172 a 300 segundos; mediana, 25-75%). O ED90 de sugamadex calculado pela regressão foi de 2,39mg/kg-1 com um intervalo de confiança de 95% (2,27 a 2,46mg/kg-1). Conclusão: o ED90 de sugamadex em pacientes com obesidade grau III ou superior foi 2,39mg/kg-1.

Inclusion complex of amiodarone hydrochloride with cyclodextrins: preparation, characterization and dissolution rate evaluation

ABSTRACT This study aimed to improve the water solubility of amiodarone hydrochloride (AMH) via inclusion complexes with β-cyclodextrin, methyl-β-cyclodextrin and 2-hydroxypropyl-β-cyclodextrin. Inclusion complexes were developed by physical mixture, coevaporation, spray-drying and freeze-drying. Solid state analysis was performed using X-ray powder diffraction, differential scanning calorimetry and scanning electronic microscopy. Thermodynamic studies demonstrate that the inclusion complexes of drug into different cyclodextrins were an exothermic process that occurred spontaneously. Water solubility and drug dissolution rates were significantly increased after the formation of inclusion complexes with the cyclodextrins evaluated in relation to the physical mixture and pure drug. The present study provides useful information for the potential application of complexation with amiodarone HCl. This may be a good strategy for the development of solid pharmaceutical dosage forms.

Preparation of cholesterol and glycerol reference materials in cyclodextrin aqueous solution / 中华检验医学杂志

Objective Preparation of aqueous reference materials for cholesterol and glycerol.Methods Study on reference materials.The certified reference materials GBW09203b and GBW09149 were weighed accurately and dissolved into 20% of methyl cyclodextrin aqueous solution to prepare six kinds of candidate reference materials of cholesterol and glycerol according to the concentration.The materials were tested for homogeneity and stability using routine methods.The reference methods of isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) were used to determine the concentration of cholesterol and glycerol to evaluate the accuracy of the certified values.Meanwhile, the blank verification test was carried out.The expanded uncertainty was the combination of standard uncertainty of measurement, unhomogeneity and instability.Results It showed that the six candidate reference materials were homogeneous and stable for at least 1 year at-70 ℃ and-20 ℃.The certified values (reference value ± expanded uncertainty,mmol/L) were as follows,for cholesterol:0.65±0.01,1.31 ±0.01,2.57±0.02,5.21±0.06,7.71±0.08,10.24±0.06;for glycerol:0.29±0.01,0.58±0.01,1.22±0.02,2.24±0.02,3.46±0.04,4.52 ±0.04.The results of reference methods were consistent with the certified values.Blank validation tests showed that the concentration of the analytes would not be affected by the reagent and the blank matrix.Conclusions Certified reference materials for cholesterol and glycerol in aqueous solution have been prepared successfully.These materials are homogeneous and stable, and the certified values are reliable.Therefore the materials have been approved to be the Certificate Reference Materials of GBW 09823, GBW 09824, GBW 09825, GBW09826, GBW09827 and GBW 09828.

Efecto citotóxico de los compuestos de inclusión de paladio (II) en la beta-ciclodextrina / Cytotoxic effect of palladium (II) inclusion compounds in beta-cyclodextrin

Resumen Introducción. Las tiosemicarbazonas y sus complejos de paladio (II) poseen actividad antineoplásica con pocos efectos secundarios, por lo cual se las considera como una nueva alternativa terapéutica. Sin embargo, existen diferencias en los rangos de la concentración inhibitoria media (CI50) asociada a la divergencia estructural y la solubilidad de los complejos, así como a la sensibilidad de los blancos celulares. La inclusión de fármacos en la beta-ciclodextrina con fines terapéuticos ha mejorado su solubilidad y estabilidad, pero los efectos de su combinación con los complejos de paladio (II) y las tiosemicarbazonas no se han comprobado aún. Objetivo. Estudiar el efecto citotóxico de los complejos de paladio en la beta-ciclodextrina. Materiales y métodos. La actividad citotóxica de los complejos de paladio en la beta-ciclodextrina se evaluó en la línea celular de cáncer de mama (MCF-7), empleando el método de la sulforodamina B. Resultados. Los ligandos MePhPzTSC y Ph2PzTSC, sus complejos de paladio (II) libres e incluidos en la beta-ciclodextrina y el cisplatino mostraron actividad citotóxica en la línea celular MCF-7; sin embargo, la citotoxicidad fue mayor con la inclusión en la beta-ciclodextrina ([Pd(MePhPzTSC)2]•ß-CD y [Pd(Ph2PzTSC)2]•ß-CD). La concentración inhibitoria media (CI50) para estos complejos se obtuvo en concentraciones de 0,14 y 0,49 μM, y con dosis hasta cinco veces inferiores comparadas con las concentraciones de los ligandos libres (1,4 y 2,9 μM), de los complejos de paladio (II) libres (0,57 y 1,24 μM) y del cisplatino (6,87 μM). Conclusiones. El uso de la beta-ciclodextrina mejoró significativamente la actividad citotóxica de las tiosemicarbazonas y sus complejos de paladio (II), lo cual probablemente está asociado al incremento de la solubilidad y biodisponibilidad del compuesto, estrategia que se puede sugerir para el diseño de futuros fármacos antineoplásicos.

Abstract Introduction: Thiosemicarbazones and palladium (II) complexes have antineoplastic activities with mild side effects, for which they are considered new alternative antineoplastic drugs. However, the IC50 ranges of these complexes vary due to differences in their structure and solubility and their sensitivities for various cellular targets. Beta-cyclodextrin is an additive used to improve the solubility and stability of various drugs for therapeutic use, but the combination of beta-cyclodextrin with palladium (II) complexes and thiosemicarbazones has not been tested yet. Objective: To study the cytotoxic effect of palladium (II) inclusion complexes in beta-cyclodextrin. Materials and methods: We tested the cytotoxic activity of palladium complexes combined with betacyclodextrin in the breast cancer cell line MCF-7 using a sulforhodamine B assay. Results: We tested the antiproliferative activity of palladium (II) complexes with and without the ligands MePhPzTSC and Ph2PzTSC and with and without beta-cyclodextrin in MCF-7 cells and compared them to that of cisplatin. All combinations showed antiproliferative activity; however, the activity was greater for the combinations that included beta-cyclodextrin: ([Pd (MePhPzTSC) 2] • ß-CD and [Pd (Ph2PzTSC) 2] • ß-CD), at concentrations of 0.14 and 0.49 μM, respectively. The IC50 for this complex was 5-fold lower than that of the ligand-free combinations (1.4 and 2.9 μM, respectively). The IC50 for free palladium (II) complex was 0.571.24 μM and that for cisplatin was 6.87 μM. Conclusions: Beta-cyclodextrin significantly enhanced the cytotoxic activities of palladium (II) complexes and thiosemicarbazones probably by improving their solubility and bioavailability. The addition of betacyclodextrin is a possible strategy for designing new anticancer drugs.

Spectroscopy study on the interaction of γ-cyclodextrin and its two derivatives with rocuronium and vecuronium / 第二军医大学学报

Objective To study the interaction of γ-cyclodextrin (-CD) and its two derivatives with rocuronium and vecuronium. Methods The interactions of γ-CD and its two derivatives HS-7, Sugammadex with rocuronium and vecuronium were characterized by Isothermal Titration Calorimetry (ITC), and the thermodynamic constant and the binding constant was determined. The binding constant and inclusion ratio of γ-CD with rocuronium and vecuronium was observed by ultraviolet- visible spectrophotometry; the binding ability of three cyclodextrins with rocuronium and vecuronium was analyzed by nuclear magnetic resonance spectroscopy COSY and1HNMR. Results The results of ITC showed that HS-7, Sugammadex combined with rocuronium and vecuronium in a 1: 1 molar ratio, and γ-CDs combined with rocuronium in a 2: 1 molar ratio, with the binding constant of HS-7 and rocuronium being (3. 44 + 2. 18) X 107 L/mol, HS-7 and vecuronium being (5. 80 + 1. 83) X 106 L/mol, Sugammadex and rocuronium being (1. 04+0. 34) X 107 L/mol, Sugammadex and vecuronium being (2. 53 + 1. 07) X 106 L/mol, and γ-CD and rocuronium being (2. 84 + 3. 41) X 104 L/mol. The results of ultraviolet-visible spectrophotometry revealed that γ-CDs combined with rocuronium and vecuronium in a 2: 1 molar ratio, with the binding constant of y-CD and rocuronium being 6. 93 X 104 L/mol, and of γ-CD and vecuronium being 5. 17 X 104 L/mol. The results of nuclear magnetic resonance spectroscopy suggested that the binding ability of HS-7 with rocuronium and vecuronium was stronger than that of Sugammadex and γ -CD. Conclusion The binding ability of HS-7 with rocuronium and vecuronium is stronger than that of Sugammadex and γ -CD, and the three methods used in this study (ITC, ultraviolet-visible spectrophotometry and nuclear magnetic resonance spectroscopy) can characterize the inclusion complex from different perspectives.

A comparative study on different processes of inclusion of pericarpium citri reticulatae - Radix Aucklandiae essential oil preparation / 国际中医中药杂志

Objective To studyeffect of different processes for preparation ofβ- cyclodextrin inclusion pericarpium citri reticulatae - Radix Aucklandiae essential oil.Methods Extract pericarpium citri reticulatae-radix aucklandiae essential oil with steam distillation method, conductβ- cyclodextrin inclusion of pericarpium citri reticulatae-radix Aucklandiae essential oil with ultrasonic method, grinding method andsaturated aqueous solution method, and detect inclusion effect respectively by polarized light microscopy observation method and TG-DTA analysis method.Results Polarized lightphenomenon disappears under a microscope for the three inclusion preparation products, and TG-DTA curve of ultrasound method is superior to that of saturated aqueous solution method and grinding method.Conclusion Polarized light microscope observation method and TG-DTA method enjoysa good effect in determination of cyclodextrin inclusion, which provides a new method for determination of cyclodextrin inclusion results.

Chitosan Nanoparticles for Topical Co-administration of the Antioxidants Glutathione and Idebenone: Characterization and In vitro Release.

Aims: The aim of this study was to explore the potential of novel nanoparticles (NPs) intended for topical administration of the hydrophilic antioxidant Glutathione and the lipophilic Idebenone. Glutathione was introduced into the NPs using two approaches: i) covalently bonded to Chitosan; ii) physically complexed with Idebenone and Sulfobutylether--cyclodextrin. Methodology: NPs were formulated using the ionic gelation technique, by dissolving the polysaccharide-forming matrix (Chitosan, Glycol chitosan, Glutathionyl Chitosan) in water or in slightly acidic solution. Idebenone was physically entrapped whereas glutathione was either physically entrapped or covalently bonded to chitosan. Physicochemical characterization of the resulting NPs included size, zeta potential measurements, antioxidant association efficiency, differential scanning calorimetry (DSC) and stability studies. Antioxidants in vitro release from the most stable NPs was assessed with Franz diffusion cells, and the in vitro antioxidant activity was evaluated by the 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical test. NP cytotoxicity was assessed on immortalized human keratinocytes (HaCaT) cell line. Results: The NPs showed smaller particle size in acidic solution than in aqueous medium, whereas zeta potential values were always positive, irrespective of the medium. Stability studies led to the choice of the aqueous formulation where Glutathione was covalently bonded to Chitosan for this study. DSC highlighted amorphization of Idebenone in these NPs. In vitro release studies showed that only Idebenone was released from the NPs. The antioxidant activity test revealed a strong effect (close to 100%) of Idebenone loaded into NPs while its aqueous solution showed no activity. No cytotoxicity in human keratinocytes was observed for the investigated NPs. Conclusion: The results of this study suggest that Idebenone can be loaded into a hydrophilic delivery system without organic solvents, often used for its solubilization, possessing high antioxidant activity. Therefore, these nanocarriers represent a promising strategy for the design of formulations for topical treatments with antioxidants.

Cyclodextrin glucanotransferase immobilization onto functionalized magnetic double mesoporous core-shell silica nanospheres

Background Cyclodextrin glucanotransferase (CGTase) from Amphibacillus sp. NPST-10 was covalently immobilized onto amino-functionalized magnetic double mesoporous core-shell silica nanospheres (mag@d-SiO2@m-SiO2-NH2), and the properties of the immobilized enzyme were investigated. The synthesis process of the nanospheres included preparing core magnetic magnetite (Fe3O4) nanoparticles, coating the Fe3O4 with a dense silica layer, followed by further coating with functionalized or non-functionalized mesoporous silica shell. The structure of the synthesized nanospheres was characterized using TEM, XRD, and FT-IR analyses. CGTase was immobilized onto the functionalized and non-functionalized nanospheres by covalent attachment and physical adsorption. Results The results indicated that the enzyme immobilization by covalent attachment onto the activated mag@d-SiO2@m-SiO2-NH2, prepared using anionic surfactant, showed highest immobilization yield (98.1%), loading efficiency (96.2%), and loading capacity 58 µg protein [CGTase]/mg [nanoparticles]) which were among the highest yields reported so far for CGTase. Compared with the free enzyme, the immobilized CGTase demonstrated a shift in the optimal temperature from 50°C to 50-55°C, and showed a significant enhancement in the enzyme thermal stability. The optimum pH values for the activity of the free and immobilized CGTase were pH 8 and pH 8.5, respectively, and there was a significant improvement in pH stability of the immobilized enzyme. Moreover, the immobilized CGTase exhibited good operational stability, retaining 56% of the initial activity after reutilizations of ten successive cycles. Conclusion The enhancement of CGTase properties upon immobilization suggested that the applied nano-structured carriers and immobilization protocol are promising approach for industrial bioprocess for production of cyclodextrins using immobilized CGTase.

Preparation and characterization of chrysin-hydroxypropyl-β-cyclodextrins in-clusion compound / 药学实践杂志

Objective To prepare the water soluble chrysin-hydroxypropyl-β-cyclodextrins inclusion compound and widen the administration path of chrysin .Methods The cogrinding method had been used to prepare chrysin-hydroxypropyl-β-cyclodextrins in-clusion compound .The PXRD, DSC and IR techniques had been used to characterize the inclusion compound .Results Chrysin and hydroxypropyl-β-cyclodextrins had formed the inclusion compound , and the formation of the inclusion compound could increase solubili-ty by 120.7 times.Conclusion The inclusion compound preparation method was simple and available , which was suitable to improve the bioavailability .

A new low molecular mass alkaline cyclodextrin glucanotransferase from Amphibacillus sp. NRC-WN isolated from an Egyptian soda lake

Background: Cyclodextrin glucanotransferase (CGTase) is one of the most industrially important enzymes used in the commercial production of cyclodextrins (CDs). Alkaliphilic bacteria have attracted much interest in the last few decades because of their ability to produce extracellular enzymes that are active and stable at high pH values. Here, we report the isolation of a new CGTase from alkaliphilic bacteria collected from Egyptian soda lakes and describe the purification and biochemical characterization of this CGTase. Results: Screening for CGTase-producing alkaliphilic bacteria from sediment and water samples collected from Egyptian soda lakes located in the Wadi Natrun valley resulted in the isolation of a potent CGTase-producing alkaliphilic bacterial strain, designated NRC-WN. Strain NRC-WN was belonging to genus Amplibacullus by 16S rDNA sequence analysis (similarity: ca. 98%). Among the tested nitrogen and carbon sources, peptone (0.15%, w/v) and soluble starch (0.4%, w/v) allowed maximal CGTase production by Amphibacillus sp. NRC-WN. CGTase was successfully purified from Amphibacillus sp. NRC-WN up to 159.7-fold through a combination of starch adsorption and anion exchange chromatography, resulting in a yield of 84.7%. SDS-PAGE analysis indicated that the enzyme was purified to homogeneity and revealed an estimated molecular mass of 36 kDa, which makes it one of the smallest CGTases reported in the literature. The purified enzyme exhibited maximum activity at 50ºC and was stable up to 70ºC, retaining 93% of its initial activity after treatment for 1 hr. Furthermore, Ca2+ ions (10 mM) significantly enhanced the thermal stability of the CGTase. The purified enzyme was active and stable over a wide pH range, showing maximal activity at pH 9.5. The enzyme was significantly stimulated by Zn2+, Ca2+ and Co2+ but was completely inhibited in the presence of Fe3+ and mercaptoethanol. The Km and Vmax values of the purified CGTase were estimated to be 0.0434 mg/ml and 3,333.3 mg β-CD/ml/min, respectively. β-CD was the predominant product of starch degradation by the Amphibacillus sp. NRC-WN CGTase, followed by α-and γ-CDs. Conclusions: A new low molecular mass alkaline CGTase was purified from a newly identified alkaliphilic Amphibacillus sp. NRC-WN isolate from the Egyptian soda lakes. The enzyme showed promising thermal and pH stability and a high affinity toward starch as a natural substrate.

Sugammadex: clinical development and practical use / 대한마취과학회지

Sugammadex is belonging to a new class of drugs: the selective relaxant binding agents. Sugammadex can reverse residual paralysis by encapsulating free circulating non depolarizing muscle relaxants. The mains advantages of sugammadex when compared with conventional anticholinesterase agents are a much faster recovery time and the unique ability, for the first time, to reverse rapidly and efficiently deep levels of neuromuscular blockade. However it only works for reversal of rocuronium or vecuronium-induced neuromuscular blockade. When administered 3 min after rocuronium the use of a large dose (16 mg/kg) can even reverse rocuronium significantly faster than the spontaneous recovery after succinylcholine.