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1.
目的 优化参白方有效部位纳米混悬剂的制备工艺,并开展纳米混悬剂的表征和升高白细胞的药效研究。方法 以参白方总多糖和总皂苷混合物为药物原料,在单因素考察的基础上,通过高压均质法,以稳定剂用量、均质压力、均质次数为影响因素,开展参白有效部位纳米混悬剂剂型工艺的正交优化和沉降稳定的观察,对制得的纳米混悬剂进行表征和升高白细胞的药效试验。结果 参白有效部位纳米混悬剂最优剂型工艺为:药物与大豆卵磷脂质量比为1:1.75,均质压力700 bar,均质次数14次。测得纳米混悬剂的粒径为(277.3±2.17)nm,PDI为0.185±0.018,Zeta电位为(-32.50±0.86)mV。给药7 d后,与模型组比较,给药7 d后纳米混悬剂高剂量组白细胞水平显著升高,给药15 d各剂量组白细胞水平显著升高(P<0.05)。结论 参白有效部位纳米混悬剂的剂型优化工艺合理、可行,制剂粒径符合纳米要求,分散均匀且稳定,具有较好的升白作用,为有效部位组成的中药纳米混悬剂的新药研究提供有益的启示。  相似文献   

2.
Abstract

The aim of this study is to prepare a nanosuspension of budesonide for respiratory delivery using nebuliser by optimising its particle size and characterising its in vitro deposition behaviour. PLA (poly lactic acid)–budesonide nanosuspension (BNS) was prepared using high-pressure emulsification/solvent evaporation method. To optimise particle size, different parameters such as PLA concentration, sonication time, and amplitude were investigated. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscope (SEM) analyses were performed to characterise the prepared PLA–budesonide nanoparticles. The in vitro aerodynamic characteristics of the PLA–BNS using a jet nebuliser were estimated and compared with that of commercially available suspension formulation of budesonide.

Budesonide-loaded PLA nanoparticles with fine particle size (an average size of 224–360?nm), narrow size distribution, and spherical and smooth surface were prepared. The optimum condition for preparation of fine particle size for aerosolisation was found to be at PLA concentration of 1.2?mg/ml and amplitude of 70 for 75?s sonication time. The in vitro aerosolisation performance of PLA–BNS compared to that of commercial budesonide indicated that it has significantly (p?<?0.05) smaller mass median aerodynamic diameter (MMAD) value with an enhancement in fine particle fraction (FPF) value. Improving the in vitro deposition of budesonide, PLA–BNS could be considered as a promising alternative suspension formulation for deep lung delivery of the drug using nebuliser.  相似文献   

3.
Abstract

To overcome the limitations of the conventional particle size reduction technologies, a novel combinative particle size reduction method for the effective production of homogeneous nanosuspensions was investigated. Ursodeoxycholic acid, a poorly soluble drug representative, was tried to prepare nanosuspension by homogenization technology and high-pressure precipitation tandem homogenization technology. It was shown that the combinative approach could significantly improve the particle size reduction effectiveness over conventional homogenization approach. The Box–Behnken design analysis for process optimization revealed that the acceptable UDCA-NS was obtained wherein the optimal values of A, B, C and D were 10%, 500?bar, 0.125 and 600?bar, respectively. SEM results demonstrated that no significant aggregation or crystals growth could be observed in the freeze-dried UDCA nanocrystals. The DSC and XRD results showed that UDCA remained in a crystalline state. Dissolution velocities of the freeze-dried UDCA-NS powder were distinctly superior compared to those of the crude powder and physical mixture. The high-pressure precipitation tandem homogenization technology can be a good choice for nanosuspension preparation of poorly soluble UDCA, due to high efficiency of particle size reduction.  相似文献   

4.
Purpose. To evaluate the dependence of fine particle dose charge (FPD charge) generated from powder inhalers on physico-chemical properties of the inhalation powder, inhaler type, deaggregation mechanism, dose number and/or retained powder. Methods. Electrostatic charges were determined on micronized powders and aerosolized fine particle doses withdrawn from two, high efficiency, multidose powder inhalers, Turbohalerand prototype Dryhaler. The behavior of terbutaline sulfate, budesonide, albuterol (sulfate and base), beclomethasone dipropionate and lactose was assessed before and after aerosolization. Results. Both inhalers conferred triboelectric FPD charges during aerosolization in the range –400 pC through +200 pC. Specific charges (charge/unit mass) on the fine particle doses of budesonide from Dryhaler were significantly less than those from Turbohaler (p < 0.01). Electrostatic charges on the potentially respirable cloud of terbutaline sulfate generated by Bricanyl Turbohaler were positive and/or negative and unpredictable. With Pulmicort Turbohaler, FPD charges on budesonide were always positive. Dryhaler was used to determine the chemical dependence of fine particle triboelectrification during the aerosolization of pure materials. A triboelectric series was constructed from the Dryhaler results ranking the powders from positive to negative as budesonide > lactose > albuterol sulfate > terbutaline sulfate albuterol beclomethasone dipropionate. Conclusions. While there was no evidence of FPD charge dependence upon dose number with either inhaler, FPD charges were dependent upon the powder under investigation, as well as the construction and deaggregation mechanism of the inhaler. The specific charge on the fine particle dose of budesonide from Turbohaler corresponded to approximately 200 electronic charges per particle, a value which is known to affect both total and regional aerosol deposition in the human lung. Electrostatic charge effects may be important determinants of aerosol behavior and should not be neglected.  相似文献   

5.
Purpose. To study the pulmonary absorption and tolerability of various formulations of the decapeptide cetrorelix acetate in rats by a new aerosol delivery system (ASTA-ADS) for intratracheal application. Methods. Using the ASTA-ADS, cetrorelix liquid formulations (aqueous solutions for ultrasonic nebulization) were firstly selected and subsequently delivered as nebulized aerosol to orotracheally cannulated rats. The pharmacologic effect (decrease of testosterone serum level) of four cetrorelix formulations was determined in rats by enzyme linked immunosorbant assay, and pharmacokinetic data were determined after measurement of cetrorelix serum level by radioimmunoassay. Histological examination of the lung was performed at the end of the experiments, and in a supplementary experiment the respiratory parameters (resistance and compliance) of rats were monitored by a validated pulmonary monitoring system during the aerosol application of the same formulations. Results. After an exposure time of 5 min, the applied formulations reduced the testosterone concentration in serum to subnormal levels (1 ng/ml) over a period of 24 h. Comparing the plasma concentration after intratracheal aerosolization with data of intravenous administration, the mean calculated bioavailabilities for the four formulations using the corrected dose (delivered—exhaled amount) were between 48.4 ± 27.0% and 77.4 ± 44.0%. The histologic examination of the lungs revealed different tolerability of the various tested formulations ranging from locally intolerable to well tolerated. The measurement of the lung function parameters did not reveal any compound or formulation related changes. Conclusions. Our studies show that cetrorelix can be effectively administered as aerosol and that intratracheal aerosolization via the ASTA-ADS provides results that are well comparable to other application routes, as demonstrated by statistical comparison of the newly obtained data with previous results from intratracheal instillation of cetrorelix solutions in rats.  相似文献   

6.
The purpose of this study was to develop nanosuspension based on combinative technology to enhance the intestinal absorption of Olmesartan medoxomil (OLM), a potent antihypertensive agent with limited oral bioavailability. Two combinative approaches were employed and then characterized. In vitro intestinal absorption of OLM nanosuspension and plain OLM was studied using non-everted rat intestinal sac model. Optimal OLM nanosuspension was prepared by a combination of ball milling and probe sonication using stabilizer, Poloxamer 407. The formula exhibited particle size of 469.9 nm and zeta potential of −19.1 mV, which was subjected to ex vivo studies. The flux and apparent permeability coefficient in intestine from OLM nanosuspension was higher than the plain drug, thereby suggesting better drug delivery.Abbreviations: OLM, olmesartan medoxomil; P407, Poloxamer 407; HPH, high pressure homogenization; PDI, polydispersity index  相似文献   

7.
Purpose. To evaluate an anomalous increase in the specific surface area of budesonide during storage postmicronization. Methods. Budesonide was micronized using a conventional air-jet mill. Surface areas and total pore volumes were measured using nitrogen sorption. Porosity was measured using mercury intrusion porosimetry. Particle size was measured using laser diffraction. Results. Budesonide exhibited a surface area increase of 22 ± 2% when stored at 25°C following micronization. The rate of surface area increase was lower at 20°C, suggesting a temperature-dependent stress relaxation mechanism for the micronized particles. The increase in surface area was accompanied by: (a) an increase in total pore volume; (b) a shift of the pore size distribution to smaller pore sizes; (c) a decrease in size of particles above 1 m; and (d) an increase in rugosity/surface roughness. Conclusions. Freshly micronized budesonide exhibited an unusual and significant postmicronization increase in specific surface area upon storage under ambient conditions. Postmicronization stress-relief by intraparticle crack formation, crack propagation with time, and particle fracture seems to be the primary mechanism behind this surface area increase.  相似文献   

8.
Background: The hygroscopicity of raffinose carrier for dry powder inhaler (DPI) was the main obstacle for its further application. Hygroscopicity-induced agglomeration would cause deterioration of aerosolization performance of raffinose, undermining the delivery efficiency.

Methods: Cyclodextrin-raffinose binary carriers (CRBCs) were produced by spray-drying so as to surmount the above issue. Physicochemical attributes and formation mechanism of CRBCs were explored in detail. The flow property of CRBCs was examined by FT4 Powder Rheometer. Hygroscopicity of CRBCs was elucidated by dynamic vapor sorption study. Aerosolization performance was evaluated by in vitro deposition profile and in vivo pharmacokinetic profile of CRBC based DPI formulations.

Results: The optimal formulation of CRBC (R4) was proven to possess anti-hygroscopicity and aerosolization performance enhancement properties. Concisely, the moisture uptake of R4 was c.a. 5% which was far lower than spray-dried raffinose (R0, c.a. 65%). R4 exhibited a high fine particle fraction value of 70.56 ± 0.61% and it was 3.75-fold against R0. The pulmonary and plasmatic bioavailability of R4 were significantly higher than R0 (p < 0.05).

Conclusion: CRBC with anti-hygroscopicity and aerosolization performance enhancement properties was a promising approach for pulmonary drug delivery, which could provide new possibilities to the application of hygroscopic carriers for DPI.  相似文献   


9.
Abstract

Objective: The purpose of this work was to prepare a stable paclitaxel nanosuspension and test it for potential use as a targeted chemotherapeutic. Different particle coatings were employed to assess their impact on cellular uptake in vitro. In vivo work was then performed to demonstrate efficacy in tumor-bearing mouse models.

Materials and method: Paclitaxel nanosuspensions were prepared using a homogenization process and coated with excipients. Surface charge was measured by zeta potential, potency by high-performance liquid chromatography, and solubility using an in-line UV probe. Cellular uptake studies were performed via flow cytometry. In vivo experiments were performed to determine residence time, maximum tolerated dose, and the efficacy of paclitaxel nanosuspensions (Paclitaxel-NS).

Results: A stable paclitaxel nanosuspension was prepared and coated with various excipients. Studies in mice showed that the nanosuspension was well-tolerated and at least as effective as the IV Taxol control in prolonging mouse survival in a head and neck cancer model as well as an ovarian cancer model with a lower overall drug dose than the traditional IV administration route.

Conclusions: The paclitaxel nanosuspension is suitable for cellular uptake. The nanosuspension was effective in prolonging life in two separate xenograft orthotopic murine cancer models through two separate routes of administration.  相似文献   

10.
Our aim was to improve the efficiency of nebulised budesonide using surface-active agents. Cationic, anionic, and nonionic detergents were added to commercial budesonide suspension, and the particle size distribution during nebulization was measured using both cascade impaction and laser diffraction. Our results showed that the emitted dose was increased after addition of cationic (p < 0.001) and nonionic detergents (p < 0.01) compared with the commercial formulation alone. The respirable fraction was increased for all detergent formulations (p < 0.001) compared with the commercial formulation. We concluded that cationic and nonionic detergent increased the total output of budesonide from the Sidestream. All detergent formulations increased the respirable fraction of nebulized budesonide.  相似文献   

11.
Purpose. To investigate some physicochemical properties of self-assembled hydrogel nanoparticles of pullulan acetate (PA) and sulfonamide conjugates, as a potential tumor targeting drug carrier responsive to tumor extracellular pH. Methods. A new class of pH-responsive polymers was synthesized by conjugating a sulfonamide, sulfadimethoxine (SDM), to succinylated pullulan acetate (coohPA). The polymers formed self-assembled PA/SDM hydrogel nanoparticles in aqueous media, which was confirmed by fluorometry and field emission-scanning electron microscopy. The pH-dependent behavior of the nanoparticles was examined by measuring transmittance, particle size and zeta potential. Adriamycin (ADR) was tested for loading into and release from the nanoparticles at various pHs. Results. The mean diameters of all PA/SDM nanoparticles tested were <70 nm, with a unimodal size distribution. The critical aggregation concentrations at pH 9.0 were as low as 3.16 g/mL. The nanoparticles showed good stability at pH 7.4, but shrank and aggregated below pH 7.0. The ADR release rate from the PA/SDM nanoparticles was pH-dependent around physiological pH and significantly enhanced below a pH of 6.8. Conclusions. The pH-responsive PA/SDM nanoparticles may provide some advantages for targeted anti-cancer drug delivery due to the particle aggregation and enhanced drug release rates at tumor pH.  相似文献   

12.

Purpose

We describe here a novel lyophilized nanosuspension technology in order to improve the dissolution rate and oral bioavailability of the insoluble drug P2X7 receptor antagonist (PRA), which is an effective antagonist to P2X7 receptor for non-steroidal anti-inflammatory.

Methods

PRA-lyophilized nanosuspension (PRA-LNS) was fabricated by anti-solvent precipitation in combination with high pressure homogenization, and then lyophilized for prolonged storage. After preparations, various characterization experiments were performed including particle size, zeta potential, surface morphology, X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), in vitro dissolution study, and in vivo pharmacokinetic study.

Results

The re-dissolved particle size of PRA-LNS was about 180~250 nm with uniform distribution, confirmed by TEM image. The drug PRA in nanosuspensions possessed crystalline form evaluated via XRPD and DSC analysis. The solubility of PRA-LNS in water was 1.52 times larger than PRA raw drug; in vitro dissolution tests showed that PRA-LNS could dissolve completely within 5 min, which is a significant improvement compared to the raw drug. The relative bioavailability of PRA-LNS is 290.70% compared to the raw drug and 177.94% compared to the physical mixture.

Conclusions

PRA-LNS could easily re-disperse in water with increased solubility, enhanced oral bioavailability, and controllable production process.
  相似文献   

13.
The rate of dissolution of drugs remains one of the most challenging aspects in formulation development of poorly water-soluble drugs. The meloxicam, a low molecular analgetic for oral administration, exhibits a slow dissolution. To improve the dissolution rate, the drug was formulated in a nanosuspension by using an emulsion–diffusion method, high-pressure homogenization or sonication. Optimization of the technological parameters (organic solvents, stabilizers, homogenization procedure and recovery of particles) allowed the formation of nanosuspensions with a particle size of 200–900 nm. SEM imaging confirmed the nanosized drug particles. Use of an SMCR method on the XRPD patterns of the nanosuspensions revealed the crystalline form of the drug and the strong interaction between meloxicam and the stabilizer. The rate of dissolution of the dried meloxicam nanosuspension was enhanced (90% in 5 min), relative to that of raw meloxicam (15% in 5 min), mainly due to the formation of nanosized particles. These results indicate the suitability of formulation procedure for preparation of nanosized poorly water-soluble drug with significantly improved in vitro dissolution rate, and thus possibly enhance fast onset of therapeutic drug effect.  相似文献   

14.
10-Hydroxycamptothecin (HCPT) is a broad-spectrum anticancer drug, while its low solubility and instability severely limit its application. In this study, HCPT nanosuspension (HCPT-NSP), also known as nanocrystal, was prepared by micro-precipitationcombined with high-pressure homogenization method. This nanosuspension was characterized by size, shape, zeta potential, drug loading efficiency and in vitro drug release behavior. Preferred formulation and process showed that particle size was (129.8±13.9) nm, PDI was 0.20±0.07, and drug loading efficiency was 36.5%±9.5%. Moreover, HCPT nanocrystal concentration reached(1.35±0.2) mg/mL in HCPT-NSP, which was more than 1000-fold higher than that of HCPT. Transmission electron microscopy (TEM) results showed that the nanosuspension was short rod in shape. X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), derivative thermogravimetric analysis (DTA) and differential scanning calorimetry (DSC) further elaborated the crystal state of the HCPT. The drug concentration-time curve of HCPT-NSP in rats was in accordance with the three-compartment model, showing prolonged half-life. Taken together, our data suggested that HCPT-NSP was a promising drug delivery system.  相似文献   

15.
Purpose. Develop metered-dose propellant-driven aerosols of proteins using tetrafluoroethane (HFC 134A) as propellant. Methods. Proteins were lyophilized with the propellant-soluble surfactants Triton X-100, Triton X-405, Laureth-9, Brij-30, Nonidet-40, and diethylene glycol monoethylether and then charged with propellants. Results. Small particle aerosols of the experimental protein bovine gamma globulin were produced. The fraction of aerosolized respirable-sized protein particles (<4–5 m) increased after dispersion of particles in propellant with agitation by shaking. Scanning electron microscopy of respirable-sized protein aerosols demonstrated bead-like particles in grape-like clusters. Vigorous shaking of propellant-suspended particles for 2 minutes or more reduced the size of clusters and reduced the diameters of the protein-containing subparticles that constituted the clusters. A 50:50 ratio of HFC 134A and dimethylether (DME) propellants improved the respirability of protein aerosols compared to HFC 134A as the sole propellant. Protein/surfactant particles first dispersed in DME and then diluted in HFC 134A propellant most efficiently produced respirable-sized, propellant-driven, protein aerosols. Conclusions. Metered-dose aerosols of respirable-sized proteins can be generated using HFC 134A and HFC 134A:DME blended propellants as an alternative to nebulized aqueous aerosols for delivering peptide-based pharmaceuticals to the respiratory tract.  相似文献   

16.
Purpose: The purpose of the present study was to formulate and evaluate nanosuspension of Valsartan (VAL), a poorly water soluble and low bioavailable drug (solubility of 0.18?mg?mL?1; 23% of oral bioavailability) with the aim of improving the aqueous solubility thus the bioavailability and consequently better anti-hypertensive activity.

Methods: Valsartan nanosuspension (VAL-NS) was prepared using high-pressure homogenization followed by lyophilisation. The screening of homogenization factors influencing nanosuspension was done by 3-factorial, 3-level Box-Behnken statistical design. Model suggested the influential role of homogenization pressure and cycles on drug nanosizing. The optimized formulation containing Poloxamer?188 (PXM 188) was homogenized for 2 cycles at 500 and 1000?bar, followed by 5 cycles at 1500 bars.

Results: The size analysis and transmission electron microscopy showed nanometric size range and uniform shape of the nanosuspension. The in vitro dissolution showed an enhanced release of VAL from nanosuspension (VAL-NS) compared to physical mixture with PXM 188. Pharmacodynamic results showed that, oral administration of VAL-NS significantly lowered (p?≤?0.001) blood pressure in comparison to non-homogenized VAL (VAL-Susp) in Wistar rat. The level of VAL in rat plasma treated with VAL-NS showed significant difference (p?≤?0.005) in Cmax (1627.47?±?112.05?ng?mL?1), Tmax (2.00?h) and AUC0→24 (13279.2?±?589.426?ng?h?mL?1) compared to VAL-Susp that was found to be 1384.73?±?98.76?ng?mL?1, 3.00?h and 9416.24?±?218.48?ng?h?mL?1 respectively. The lower Tmax value, proved the enhanced dissolution rate of VAL.

Conclusion: The overall results proved that newly developed VAL-NS increased the plasma bioavailability and pharmacodyanamic potential over the reference formulation containing crude VAL.  相似文献   

17.
Spray coated pellets as carrier system for mucoadhesive drug nanocrystals.   总被引:1,自引:0,他引:1  
High pressure homogenization can be employed to produce drug nanocrystals with a number of advantages, like improved solubility behaviors, better drug targeting or even increased mucoadhesiveness. To obtain a controlled drug delivery system it is necessary to transform the resulting nanosuspension into a solid dosage form. The present study shows the feasibility to use a mucoadhesive nanosuspension of poorly soluble hydrocortisone acetate produced by high pressure homogenization as layering dispersion in a fluidized bed process, followed by the application of an enteric coating to achieve a controlled drug release. To point out the advantages of drug nanocrystals the new fomulation was compared with a formulation containing micronized drug. Both formulations were characterized with regard to their particle size and crystallinity by using laser diffractometry, photon correlation spectroscopy and X-ray diffraction. The pellet morphology was characterized by using the environmental scanning electron microscopy (ESEM). In the in vitro dissolution tests an accelerated dissolution velocity and an increased drug release could be shown for the pellets containing drug nanocrystals.  相似文献   

18.
目的制备1,3-二羟基异丙氧基-琥珀酸-8-莪术醇酯纳米混悬剂(Cur-p-NS),并考察其一般特性、载药量和体外释放特性。方法采用超声–溶剂沉淀法制备Cur-p-NS,考察其粒度大小,多聚分散系数和Zeta电位。结果 Cur-p-NS的平均粒径为162.60±2.12 nm,多分散系数为0.182±0.002,Zeta电位为-24.60±8.97 m V,平均载药量为0.942 mg/mg,累积释放率可达到77%。结论 Cur-p-NS制备工艺简单和效果好,具有持续释放的特性。  相似文献   

19.
Abstract

The purpose of this research work was to formulate the stable nanosuspension of Ginkgo biloba to increase its oral bioavailability. To achieve this goal, initially nanosuspensions of G. biloba were prepared with six different stabilisers. Afterwards, other formulation conditions were optimised with response surface methodology. Stabiliser screening study selected sodium lauryl sulphate as stabiliser to formulate the nanosuspension of G. biloba by antisolvent precipitation method. Under suggested optimal conditions of software, nanosuspension of G. biloba with mean particle size 139.5?nm, polydispersity index 0.258 and zeta potential 58.7?mV was prepared. Atomic force microscopy showed sheet like shape and very well distribution of G. biloba nanoparticles with approximate height of 15–30nm. Optimised nanosuspension of G. biloba demonstrated greater in-vitro dissolution and more plasma concentration of quercetin in G. biloba nanosuspension administrated rats in comparison to coarse suspension. Moreover, cytotoxicity study revealed no toxic effects of formulated nanosuspension.  相似文献   

20.
目的 探讨不同非密闭雾化方式在不合作患儿接受布地奈德雾化治疗中的应用效果。方法 选取本院门诊270例3岁以下使用布地奈德雾化治疗的患儿,采用随机数字表法将患儿分为Pari雾化系统、Philips雾化系统及Salter雾化系统3个治疗组,毎组90例,各组又依据面罩距离面部0 cm、2 cm、4 cm分为3个小组,毎组30例,分别测量各组雾化气流流速及吸入雾化颗粒量占总雾化颗粒量的比例。采用方差分析及Bonferroni进行统计分析。结果 雾化气流流速及雾化吸入量在不同雾化系统组间差异有统计学意义(P<0.05)。在3种距离下,Pari系统均能使患儿吸入最多量的雾化颗粒,其次是Salter系统,再是Philips系统,与此相反,气流流速Pari系统最低。Pari系统离开面部4 cm及Salter系统离开面部2 cm的吸入量均高于Philips系统0 cm的吸入量。结论 选择合适的非密闭雾化系统方式,是提高不合作患儿布地奈德雾化治疗的有效方式。  相似文献   

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