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Formulation and in vitro evaluation of nifedipine-controlled release tablet: Influence of combination of hydrophylic and hydrophobic matrix forms
Derakhshandeh Katayoun,Soleymani Marzieh
Asian Journal of Pharmaceutics , 2010,
Abstract: The aim of the present work was to develop controlled release matrix formulation of nifedipine and investigate the effects of both hydrophilic and hydrophobic polymers on in vitro drug release. Matrix tablets were prepared by wet granulation technique using different concentration of hydroxy propyl methyl cellulose (HPMC), ethyl cellulose (EC), compressible Eudragits (RSpo and RLpo) and their combination in different ratios to examine their influence on tablet properties and drug release profile. Tablets were evaluated by measurement of hardness, friability, content uniformity, weight variation and drug release pattern. Release studies were carried out using USP type II apparatus in 900 ml of sodium phosphate buffer (pH 7.4) with 0.5% (w/v) SDS. The amount of drug released was determined at 238 nm by UV-visible spectrophotometer.In vitro dissolution studies indicated that hydrophobic polymers significantly reduced the rate of drug release compared to hydrophilic ones in 12 hrs and combination of both polymers exhibited the best release profile to sustain the drug release for prolong period of time. As a result, the tablet containing HPMC:EC in ratio of 0.75:1 showed better controlled release pattern over a period of 12 hrs. In selected formulation, the calculated regression coefficients for release models fitted best to zero-order models.
Thermosensitive Pluronic hydrogel: prolonged injectable formulation for drug abuse
Katayoun Derakhshandeh, Mahtab Fashi, Seyedalireza Seifoleslami
Drug Design, Development and Therapy , 2010, DOI: http://dx.doi.org/10.2147/DDDT.S13289
Abstract: mosensitive Pluronic hydrogel: prolonged injectable formulation for drug abuse Original Research (4832) Total Article Views Authors: Katayoun Derakhshandeh, Mahtab Fashi, Seyedalireza Seifoleslami Published Date September 2010 Volume 2010:4 Pages 255 - 262 DOI: http://dx.doi.org/10.2147/DDDT.S13289 Katayoun Derakhshandeh1, Mahtab Fashi1, Seyedalireza Seifoleslami2 1Department of Pharmaceutics, Faculty of Pharmacy, University of Medical Science, Kermanshah; 2Research and Development Department, Forensic Medicine Organization, Kermanshah, Iran Objective: The main objective of this study was to investigate thermosensitive Pluronic F-127 (PF-127) hydrogel for the modified release of a potent alcohol and opioid antagonist, naltrexone (NTX) hydrochloride, in a subcutaneous injectable dosage form. Methods: The NTX hydrogels were prepared by the cold method, and the in vitro release profiles of various formulations were evaluated at 37°C using the Franz diffusion cell system. We examined the different PF-127 concentrations, pH of solution, and inorganic salts on drug release from these gels. Results: The data showed an increase in PF-127 content from 20% to 35%, resulting in a decrease in the rate of NTX release. Among the formulations prepared in different pH solutions, pH 7.4 produced the slowest drug release rate. The addition of inorganic salts had no significant effect on drug release. However, these factors appeared to have limited effects on drug release rate. Therefore, to achieve a sustained-release formulation, a NTX and triacetyl β-cyclodextrin (TAβCD) complex was evaluated. The binary systems of NTX/TAβCD in different molar ratios were prepared by the kneading method, and complex formation was demonstrated by differential scanning calorimetry. Conclusion: The results of the current in vitro study indicate that PF-127 gel formulations containing drug complexes with hydrophobic cyclodextrin could be useful for the preparation of a controlled delivery system of water-soluble drugs such as NTX, for a period of more than 140 hours.
On the mechanism of agglomeration in suspension
Maryam Maghsoodi,Katayoun Derakhshandeh,Zahra Yari
Advanced Pharmaceutical Bulletin , 2012,
Abstract: Purpose: Agglomeration in suspension is a size enlargement method that facilitates operation of solid processing and preserves the solubilization properties of fine particles. A small quantity of binder liquid is added into a suspension of microparticles, directly in the stirred vessel where the precipitation or crystallization took place. This study deals with the evaluation of the effect of agitation time before and after addition of binder liquid on agglomerates properties in order to give some insights into the mechanism of the formation of the agglomerates. Methods: Carbamazepine is used as a model drug and isopropyl acetate is used as binder liquid. The agglomerates characterization includes the particle size, morphology and density. Results: The results showed that, by increasing the agitation time before addition of binder liquid, smaller agglomerates with less density and irregular forms composed of larger crystals were obtained. However, with increasing agitation time after addition of binder liquid the agglomerates size and density increases and morphology improves. Indeed, by continuing agitation along the course of agglomeration the properties of the particles change gradually but substantially. Conclusion: With optimized agitation time before and after addition of binder liquid, spherical and dense agglomerates can be obtained.
Thermosensitive Pluronic® hydrogel: prolonged injectable formulation for drug abuse
Katayoun Derakhshandeh,Mahtab Fashi,Seyedalireza Seifoleslami
Drug Design, Development and Therapy , 2010,
Abstract: Katayoun Derakhshandeh1, Mahtab Fashi1, Seyedalireza Seifoleslami21Department of Pharmaceutics, Faculty of Pharmacy, University of Medical Science, Kermanshah; 2Research and Development Department, Forensic Medicine Organization, Kermanshah, IranObjective: The main objective of this study was to investigate thermosensitive Pluronic F-127 (PF-127) hydrogel for the modified release of a potent alcohol and opioid antagonist, naltrexone (NTX) hydrochloride, in a subcutaneous injectable dosage form.Methods: The NTX hydrogels were prepared by the cold method, and the in vitro release profiles of various formulations were evaluated at 37°C using the Franz diffusion cell system. We examined the different PF-127 concentrations, pH of solution, and inorganic salts on drug release from these gels.Results: The data showed an increase in PF-127 content from 20% to 35%, resulting in a decrease in the rate of NTX release. Among the formulations prepared in different pH solutions, pH 7.4 produced the slowest drug release rate. The addition of inorganic salts had no significant effect on drug release. However, these factors appeared to have limited effects on drug release rate. Therefore, to achieve a sustained-release formulation, a NTX and triacetyl β-cyclodextrin (TAβCD) complex was evaluated. The binary systems of NTX/TAβCD in different molar ratios were prepared by the kneading method, and complex formation was demonstrated by differential scanning calorimetry.Conclusion: The results of the current in vitro study indicate that PF-127 gel formulations containing drug complexes with hydrophobic cyclodextrin could be useful for the preparation of a controlled delivery system of water-soluble drugs such as NTX, for a period of more than 140 hours.Keywords: naltrexone, thermosensitive hydrogel, prolonged release, triacetyl β-cyclodextrin, kneading method
Preparation and in vitro characterization of 9-nitrocamptothecin-loaded long circulating nanoparticles for delivery in cancer patients
Katayoun Derakhshandeh, Marzieh Soheili, Simin Dadashzadeh, et al
International Journal of Nanomedicine , 2010, DOI: http://dx.doi.org/10.2147/IJN.S11586
Abstract: eparation and in vitro characterization of 9-nitrocamptothecin-loaded long circulating nanoparticles for delivery in cancer patients Original Research (4970) Total Article Views Authors: Katayoun Derakhshandeh, Marzieh Soheili, Simin Dadashzadeh, et al Published Date July 2010 Volume 2010:5 Pages 463 - 471 DOI: http://dx.doi.org/10.2147/IJN.S11586 Katayoun Derakhshandeh1, Marzieh Soheili1, Simin Dadashzadeh2, Reza Saghiri3 1Department of Pharmaceutics, Faculty of Pharmacy, University of Medical Science, Kermanshah 67145-1673, Iran; 2Department of Pharmaceutics, Faculty of Pharmacy, Shaheed Beheshti University of Medical Science, Tehran, Iran; 3Deptartment of Biochemistry, Pasteur Institute, Tehran, Iran Abstract: The purpose in this study was to investigate poly(ethylene glycol)-modified poly (d,l-lactide-co-glycolide) nanoparticles (PLGA-PEG-NPs) loading 9-nitrocamptothecin (9-NC) as a potent anticancer drug. 9-NC is an analog of the natural plant alkaloid camptothecin that has shown high antitumor activity and is currently in the end stage of clinical trial. Unfortunately, at physiological pH, these potent agents undergo a rapid and reversible hydrolysis with the loss of antitumor activity. Previous researchers have shown that the encapsulation of this drug in PLGA nanoparticles could increase its stability and release profile. In this research we investigated PLGA-PEG nanoparticles and their effect on in vitro characteristics of this labile drug. 9-NC-PLGA-PEG nanoparticles with particle size within the range of 148.5 ± 30 nm were prepared by a nanoprecipitation method. The influence of four different independent variables (amount of polymer, percent of emulsifier, internal phase volume, and external phase volume) on nanoparticle drug-loading was studied. Differential scanning calorimetry and X-ray diffractometry were also evaluated for physical characterizing. The results of optimized formulation showed a narrow size distribution, suitable zeta potential (+1.84), and a drug loading of more than 45%. The in vitro drug release from PLGA-PEG NPs showed a sustained release pattern of up to 120 hours and comparing with PLGA-NPs had a significant decrease in initial burst effect. These experimental results indicate that PLGA-PEG-NPs (versus PLGA-NPs) have a better physicochemical characterization and can be developed as a drug carrier in order to treat different malignancies.
Preparation and in vitro characterization of 9-nitrocamptothecin-loaded long circulating nanoparticles for delivery in cancer patients
Katayoun Derakhshandeh,Marzieh Soheili,Simin Dadashzadeh,et al
International Journal of Nanomedicine , 2010,
Abstract: Katayoun Derakhshandeh1, Marzieh Soheili1, Simin Dadashzadeh2, Reza Saghiri31Department of Pharmaceutics, Faculty of Pharmacy, University of Medical Science, Kermanshah 67145-1673, Iran; 2Department of Pharmaceutics, Faculty of Pharmacy, Shaheed Beheshti University of Medical Science, Tehran, Iran; 3Deptartment of Biochemistry, Pasteur Institute, Tehran, IranAbstract: The purpose in this study was to investigate poly(ethylene glycol)-modified poly (d,l-lactide-co-glycolide) nanoparticles (PLGA-PEG-NPs) loading 9-nitrocamptothecin (9-NC) as a potent anticancer drug. 9-NC is an analog of the natural plant alkaloid camptothecin that has shown high antitumor activity and is currently in the end stage of clinical trial. Unfortunately, at physiological pH, these potent agents undergo a rapid and reversible hydrolysis with the loss of antitumor activity. Previous researchers have shown that the encapsulation of this drug in PLGA nanoparticles could increase its stability and release profile. In this research we investigated PLGA-PEG nanoparticles and their effect on in vitro characteristics of this labile drug. 9-NC-PLGA-PEG nanoparticles with particle size within the range of 148.5 ± 30 nm were prepared by a nanoprecipitation method. The influence of four different independent variables (amount of polymer, percent of emulsifier, internal phase volume, and external phase volume) on nanoparticle drug-loading was studied. Differential scanning calorimetry and X-ray diffractometry were also evaluated for physical characterizing. The results of optimized formulation showed a narrow size distribution, suitable zeta potential (+1.84), and a drug loading of more than 45%. The in vitro drug release from PLGA-PEG NPs showed a sustained release pattern of up to 120 hours and comparing with PLGA-NPs had a significant decrease in initial burst effect. These experimental results indicate that PLGA-PEG-NPs (versus PLGA-NPs) have a better physicochemical characterization and can be developed as a drug carrier in order to treat different malignancies.Keywords: long circulating nanoparticle, 9-nitrocamptothecin, in vitro characterization
A study on organizational entrepreneurship on economic growth
Afsaneh Derakhshandeh
Management Science Letters , 2013,
Abstract: Today, the positive impact of entrepreneurship in the economy has been globally accepted. Entrepreneurs could provide efficient techniques to face with upcoming economic challenges. In this paper, we first investigate the effect of entrepreneurship on growth of economy over the period 2005- 2011. Then we study the impact of four factors including Gross domestic product per worker, Growth in capital per worker, New firm creation and Technological innovation intensity on economic growth. The proposed model of this paper uses ordinary least square technique to investigate the relationship between four independent variables and economic growth. The results show that gross domestic product per worker is the only variable, which is statistically meaningful when the level of significance is five percent and the impact of other three variables including growth in capital per worker, new firm creation and technological innovation intensity are not statistically meaningful. In other word, as we see a 1% increase in gross domestic product per worker we could expect 8.712% increase in economic growth.
The effects of e-business on organizational performance
Afsaneh Derakhshandeh
Management Science Letters , 2012,
Abstract: Information technology plays an important role in increasing organizational cooperation both inside an organization and among different firms. In fact, may organizations have shared information though the recent advances of information technology and they have been able to increase the performance of their organizations, significantly. In this paper, we present an empirical study to investigate the relationship between e-business and intra and extra organizational cooperation. The results indicate that e-business directly increase intra organizational performance, indirectly increase organizational cooperation. Extra organizational performance directly increase organization performance, inside cooperation also indirectly influence inside cooperation through extra organization cooperation.
Factorization numbers of finite abelian groups
Mohammad Farrokhi Derakhshandeh Ghouchan
International Journal of Group Theory , 2013,
Abstract: The number of factorizations of a finite abelian group as the product of two subgroups is computed in two different ways and a combinatorial identity involving Gaussian binomial coefficients is presented .
A relationship between leadership style and perceived organizational effectiveness by directors and managers in organizations
Afsaneh Derakhshandeh,Reza Gholami
Management Science Letters , 2012,
Abstract: Management is the basis of all necessary changes required for any organization. In order to reach organizational objectives, it is necessary to use human resources as effectively as possible. All management team members need to know about their own thinking as well as their ideas on reaching common objectives with better outcomes. In this paper, we present an empirical investigation to study the relationship between leadership style and perceived organizational effectiveness by directors and managers in organizations. The proposed study distributes a questionnaire consists of 37 questions among some management team of Agricultural ministry in one of the provinces of Iran. The main hypothesis of this survey examines the positive relationship between leadership style and perceived organizational effectiveness. The other hypothesis is associated with the supportive leadership style and perceived organization effectiveness and the third question is associated with democratic leadership style and perceived organization effectiveness. The results of Spearman-Pearson test confirm all three results, which indicate there is a meaningful and positive relationship between leadership style and perceived organizational effectiveness.
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