scholarly journals Effect of Polymers nature and Stirring Speeds on Physicochemical Properties and the Controlled Release of Allopurinol-loaded Microspheres

2021 ◽  
Vol 66 (1) ◽  
Author(s):  
Karima Badis ◽  
Haouaria Merine ◽  
Youssef Ramli ◽  
OumCheikh Larbi ◽  
Cherifa Hakima Memou
Keyword(s):  
Fourier Transforms ◽  
Release Kinetics ◽  
Drug Loading ◽  
In Vitro Release ◽  
Release Mechanism ◽  
Release Studies ◽  
Fourier Transforms Infrared Spectroscopy ◽  
The Mean ◽  
Solvent Evaporation Process

Abstract. Allopurinol is an antigout drug therapy, commonly used in the treatment of chronic gout or hyperuricaemia associated with treatment of diuretic conditions. In the present study, new formulations based on Allopurinol, have been prepared with the microencapsulation by solvent evaporation process. Microspheres were prepared using pure Allopurinol and polymeric matrices (ethylcellulose EC, poly (ε-caprolactone) PCL, β-cyclodextrin CD and hydroxypropylmethylcellulose HPMC) at different compositions and stirring speeds to investigate the effect of these parameters on loading efficiency and drug release kinetics. The formulations produced were characterized by various methods : Fourier transforms infrared spectroscopy (FTIR), X-ray powder diffractometry, optical microscopy, surface morphology by scanning electron microscopy (SEM) and drug loading, as well as in vitro release studies in the simulated stomach tract. Depending on the stirring speed and the composition of the microparticles, the active ingredient loading is in a range from 10.46 ± 1.45 to 46.40 ± 0.5%. The microspheres are spherical and the mean Sauter diameter (d32) of the microparticles obtained is smaller and is in the range of 47.71 to 151.01 µm. Different release profiles were obtained and show that the release rate is strongly influenced by the characteristics of the microparticles ; namely, the stirring rates and the composition of the microparticles. The release mechanism was identified by modelling using Higuchi and Korsmeyer-Peppas models.   Resumen. Alopurinol es una droga terapéutica para tratar la gota, y se utiliza en el tratamiento de gota crónica o hiperuricemia asociada con el tratamiento de condiciones diuréticas. En este estudio, nuevas formulaciones basadas en Alopurinol se prepararon mediante microencapsulación por el proceso de evaporación de disolvente. Microesferas se prepararon usando Alopurinol puro y diferentes matrices poliméricas (etil-celulosa EC, poli(-caprolactona) PCL, β-cyclodextrina CD e hidroxipropil-metil-celulose HPMC) en diferentes composiciones y velocidades de agitación, para investigar el efecto de estos parámetros en la eficiencia de carga y en la cinética de liberación del fármaco. Las formulaciones obtenidas fueron caracterizadas por diferentes técnicas : Espectroscopía infrarroja de transformadas de Fourier (FTIR), difractometría de rayos X de polvos, microscopía óptica, morfología de superficies mediante microscopía electrónica de barrido electrónico, y la eficiencia de carga del fármaco, así como estudios de liberación in vitro en tracto estomacal simulado. Dependiendo de la velocidad de agitación y la composición de las micropartículas, la carga del ingrediente activo se encuentra en el rango de 10.46 ± 1.45 a 46.40 ± 0.5%. Las microesferas son esféricas y el diámetro medio de Sauter (d32) de las micropartículas obtenidas es menor, y se encuentra en el rango de 47.71 a 151.01 µm. Se obtuvieron diferentes perfiles de liberación y se observa que la velocidad de liberación está influenciada principalmente por las características propias de la producción de las micropartículas ; en particualr, las velocidades de agitación y las composición de las micropartículas. El mecanismo de liberación se ajusta mejor a los modelos matemáticos de Higuchi and Korsmeyer-Peppas.

scholarly journals Release Kinetics Study of Azithromycin from Bi-layered Tablets

2017 ◽  
Vol 20 (1) ◽  
pp. 54-63
Author(s):  
FM Shah Noman Ul Bari ◽  
Muhammad Rashedul Islam ◽  
Md Mizanur Rahman Moghal ◽  
Israt Jahan Ira
Keyword(s):  
Release Kinetics ◽  
In Vitro Release ◽  
Methyl Cellulose ◽  
Pharmaceutical Journal ◽  
High Viscosity ◽  
Release Mechanism ◽  
Low Viscosity ◽  
Release Studies ◽  
Vitro Release

The objective of this study was to analysis in vitro release kinetics of Azithromycin from bi-layer tablets prepared by direct compression using high viscosity to low viscosity grades of hydroxypropyl methyl cellulose (HPMC K15M, HPMC K4M, HPMC 50 cps), Carbopol 934p and Carbopol 974p. In addition, it also includes evaluating the effect of formulation variables like polymer proportion and polymer viscosity on the release of Azithromycin. In vitro release studies were performed using USP Type-II (Rotating paddle method) at 100 rpm. The dissolution medium consisted of 0.1N HCl (900 ml) for the first 2 hr and the phosphate buffer (pH 6.0) from 3rd to 10th hour. From twenty five different formulations (F-1 to F-25) based on polymer variation, model-dependent and independent methods were used for data analysis and the best results were observed for HPMC 50cps in Korsmeyer- Peppas (R2=0.995 on F-23) kinetic model. The release mechanism of all formulations was Fickian.Bangladesh Pharmaceutical Journal 20(1): 54-63, 2017

Preparation and in vitro Evaluation of Bioadhesive Microparticulate System

1970 ◽  
Vol 1 (3) ◽  
pp. 257-266
Author(s):  
Nagda C. D. ◽  
Chotai N. P. ◽  
Patel S. B. ◽  
Soni T. J ◽  
Patel U. L
Keyword(s):  
Drug Loading ◽  
In Vitro Release ◽  
Phenyl Acetic Acid ◽  
Solvent Evaporation Method ◽  
Elimination Half ◽  
Release Studies ◽  
Differential Scanning Colorimetry ◽  
Polymer Interactions ◽  
Vitro Release

Aceclofenac (ACE) is NSAIDs of a phenyl acetic acid class. It is indicated in arthritis and osteoarthritis, rheumatoid arthritis, ankylosing spondylitis. It has short elimination half life of 4 hours. The objective of the study is to design, characterize and evaluate bioadhesive microspheres of ACE employing carbopol (CP) as bioadhesive polymer. Bioadhesive microspheres of ACE were prepared by solvent evaporation method. The prepared microspheres were free flowing and spherical in shape and characterized for drug loading, mucoadhesion test, infrared spectroscopy (IR), differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The in-vitro release studies were performed using pH 6.8 phosphate buffer. The drug loaded microspheres in a ratio of 1:5 showed 47% of drug entrapment; percentage mucoadhesion was 81% and 89% release in 10 h. The infrared spectra and DSC showed stable character of aceclofenac in the drug loaded microspheres and revealed the absence of drug-polymer interactions. SEM studies showed that the microspheres are spherical and porous in nature. The in vitro release profiles from microspheres of different polymer-drug ratios followed Higuchi model.

scholarly journals In vitro Release Kinetics Study of Ranolazine from Swellable Hydrophilic Matrix Tablets

1970 ◽  
Vol 8 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Mohammad Nezab Uddin ◽  
Ishtiaq Ahmed ◽  
Monzurul Amin Roni ◽  
Muhammad Rashedul Islam ◽  
Mohammad Habibur Rahman ◽  
...  
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
Release Kinetics ◽  
In Vitro Release ◽  
High Viscosity ◽  
Matrix Tablets ◽  
Release Studies ◽  
The Matrix ◽  
Vitro Release

The objective of this study was to design oral sustained release matrix tablets of Ranolazine usinghydroxypropyl methylcellulose (HPMC) as the retardant polymer and to study the effect of formulation factors suchas polymer proportion and polymer viscosity on the release of drug. In vitro release studies were performed usingUSP type II apparatus (paddle method) in 900 mL of 0.1N HCl at 100 rpm for 12 hours. The release kinetics wasanalyzed using the zero-order, first order, Higuchi and Korsmeyer-Peppas equations to explore and explain themechanism of drug release from the matrix tablets. In vitro release studies revealed that the release rate decreasedwith increase in polymer proportion and viscosity grade. Mathematical analysis of the release kinetics indicated thatthe nature of drug release from the matrix tablets was dependent on drug diffusion and polymer relaxation andtherefore followed non-Fickian or anomalous release. The developed controlled release matrix tablets of Ranolazineprepared with high viscosity HPMC extended release up to 12 hours.Key words: Ranolazine; Sustained release; Methocel E50 Premium LV; Methocel K100LV CR; Methocel K4M CR;Methocel K15M CR.DOI: 10.3329/dujps.v8i1.5333Dhaka Univ. J. Pharm. Sci. 8(1): 31-38, 2009 (June)

scholarly journals DESIGN AND IN VITRO/IN VIVO EVALUATION OF EXTENDED RELEASE MATRIX TABLETS OF NATEGLINIDE

2018 ◽  
Vol 7 (6) ◽  
Author(s):  
Mohini Sihare ◽  
Rajendra Chouksey
Keyword(s):  
Drug Release ◽  
Release Kinetics ◽  
In Vitro Release ◽  
Release Profile ◽  
Matrix Tablets ◽  
In Vivo Studies ◽  
Release Mechanism ◽  
In Vivo Evaluation

Aim: Nateglinide is a quick acting anti-diabetic medication whose potent activity lasts for a short duration. One of the dangerous side effects of nateglinide administration is rapid hypoglycemia, a condition that needs to be monitored carefully to prevent unnecessary fatalities. The aim of the study was to develop a longer lasting and slower releasing formulation of nateglinide that could be administered just once daily. Methods: Matrix tablets of nateglinide were prepared in combination with the polymers hydroxypropylmethylcellulose (HPMC), eudragits, ethyl cellulose and polyethylene oxide and the formulated drug release patterns were evaluated using in vitro and in vivo studies. Conclusion: Of the seventeen formulated matrix tablets tested, only one formulation labelled HA-2 that contained 15% HPMC K4M demonstrated release profile we had aimed for. Further, swelling studies and scanning electron microscopic analysis confirmed the drug release mechanism of HA-2. The optimized formulation HA-2 was found to be stable at accelerated storage conditions for 3 months with respect to drug content and physical appearance. Mathematical analysis of the release kinetics of HA-2 indicated a coupling of diffusion and erosion mechanisms. In-vitro release studies and pharmacokinetic in vivo studies of HA-2 in rabbits confirmed the sustained drug release profile we had aimed for. Keywords: Hydroxypropylmethylcellulose, Matrix tablets, Nateglinide, Sustained release

scholarly journals FABRICATION OF NANO CLAY INTERCALATED POLYMERIC MICROBEADS FOR CONTROLLED RELEASE OF CURCUMIN

2021 ◽  
pp. 206-215
Author(s):  
DHARMENDER PALLERLA ◽  
SUMAN BANOTH ◽  
SUNKARI JYOTHI
Keyword(s):  
Drug Release ◽  
In Vitro Release ◽  
Controlled Drug Release ◽  
Fickian Diffusion ◽  
Simulated Gastric Fluid ◽  
Release Mechanism ◽  
Release Studies ◽  
Swelling Studies ◽  
Vitro Release

Objective: The objective of this study was to formulate and evaluate the Curcumin (CUR) encapsulated sodium alginate (SA)/badam gum (BG)/kaolin (KA) microbeads for controlled drug release studies. Methods: The fabricated microbeads were characterized by fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (X-RD), and scanning electron microscopy (SEM). Dynamic swelling studies and in vitro release kinetics were performed in simulated intestinal fluid (pH 7.4) and simulated gastric fluid (pH 1.2) at 37 °C. Results: FTIR confirms the formation of microbeads. DSC studies confirm the polymorphism of CUR in drug loaded microbeads which indicate the molecular level dispersion of the drug in the microbeads. SEM studies confirmed the microbeads are spherical in shape with wrinkled and rough surfaces. XRD studies reveal the molecular dispersion of CUR and the presence of KA in the developed microbeads. In vitro release studies and swelling studies depend on the pH of test media, which might be suitable for intestinal drug delivery. The % of drug release values fit into the Korsmeyer-Peppas equation and n values are obtained in the range of 0.577-0.664, which indicates that the developed microbeads follow the non-Fickian diffusion drug release mechanism. Conclusion: The results concluded that the CUR encapsulated microbeads are potentially good carriers for controlled drug release studies.

scholarly journals Influence of sterilization on the drug release behaviour of drug coated silicone

2021 ◽  
Vol 7 (2) ◽  
pp. 672-675
Author(s):  
Katharina Wulf ◽  
Stefan Raggl ◽  
Thomas Eickner ◽  
Gerrit Paasche ◽  
Niels Grabow
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Polymer Coating ◽  
Drug Loading ◽  
In Vitro Release ◽  
Physical Chemical ◽  
Release Studies ◽  
Vitro Release ◽  
Dual Drug

Abstract Sterilization processes ensure sterility of drug delivery systems, but may negatively affect the properties of biomaterials and incorporated drugs by changing their physical, chemical, mechanical properties and drug release behaviour. Therefore, it is important to investigate their influence. In this study, the influence of ethylene oxide (EtO) sterilization on the drug loading and release behaviour of incorporated Diclofenac (DCF) in a Poly-L-lactide (PLLA) coating and Dexamethasone (DMS) in the silicone carrier is presented. Silicone samples containing DMS were coated with PLLA containing DCF varying in layer thickness (5, 10, and 20 μm). Half of the samples underwent EtO sterilization, the other half was not sterilized. All un-/sterilized sample surfaces were in view of the morphology and hydrophilicity examined. Furthermore, in vitro release studies of DMS and DCF were conducted. The sterilized sample surfaces showed no morphological and hydrophilicity changes. The DCF and DMS loadings were similar for the sterile and untreated samples. This also applied to the in vitro DMS release profiles apart from the end of the studies where slight differences were evident. The results indicate that both drugs loaded in the polymer coating and the silicone were not impaired by the sterilization process. Thus, EtO sterilization appears suitable for DMS containing silicone and DCF incorporated PLLA coatings as a dual drug delivery system.

scholarly journals Synthesis and Characterization of Lyophilized Chitosan-Based Hydrogels Cross-Linked with Benzaldehyde for Controlled Drug Release

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Fouad Damiri ◽  
Yahya Bachra ◽  
Chaimaa Bounacir ◽  
Asmae Laaraibi ◽  
Mohammed Berrada
Keyword(s):  
Ascorbic Acid ◽  
Drug Release ◽  
Drug Loading ◽  
In Vitro Release ◽  
Controlled Drug Release ◽  
Tween 20 ◽  
Release Mechanism ◽  
Synthetic Process ◽  
Chitosan Salt

In this study, chitosan-based hydrogels were produced by incorporating three drugs with a different solubility into a polymer matrix. The lyophilized chitosan salt was prepared using an innovative and less-expensive synthetic process by the freeze-drying technique. Firstly, the three drugs (caffeine, ascorbic acid, and 5-fluorouracil (5-FU)) were selected as model drugs to test the in vitro release behavior of the hydrogel. The drugs were solubilized in chitosan salt, lyophilized, and cross-linked with benzaldehyde involving the formation of a Schiff base with (–C=N-) linkage to produce a physical hydrogel. Subsequently, the physicochemical properties of N-benzyl chitosan and lyophilized chitosan salt were evaluated by Fourier-transform infrared (FTIR) spectra, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The intrinsic viscosity of the conventional chitosan was determined by the Mark–Houwink–Sakurada equation. Moreover, the kinetics of hydrogel swelling and drug release were studied by the UV-visible method at physiological conditions (pH = 7.4 at 37°C). The results show that lyophilized N-benzyl chitosan had a maximum swelling ratio of 720 ± 2% by immersion in phosphate-buffered saline solutions (PBS) (pH = 7.4 at 37°C). In vitro drug releases were evaluated in PBS, and the obtained results show that the maximum drug release after 24 h was 42% for caffeine, 99% for 5-FU, and 94% for ascorbic acid. Then, to optimize the cumulative release of caffeine, Tween 20 was added and 98% as a release percentage was obtained. The drug-loading results were investigated with the Korsmeyer–Peppas kinetic model and applied to determine the drug release mechanism.

Formulation and Optimization of Solid-Lipid Nano-particles of the Anticancer Drug Bortezomib

2019 ◽  
Vol 12 (2) ◽  
pp. 4461-4475
Author(s):  
Taraka Sunil Kumar K ◽  
M. Mohan Varma ◽  
Ravi Prakash P
Keyword(s):  
Release Kinetics ◽  
Drug Loading ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Nano Particles ◽  
Cancer Drug ◽  
Solid Lipid ◽  
Zero Order Release ◽  
Presystemic Metabolism

Solid-lipid nanoparticles (SLNs) are an alternative carrier system used for loading the drug for targeting, improving the bioavailability by increasing its solubility, and protecting the drug from presystemic metabolism. The avoidance of presystemic metabolism is due to the nanometric size range so that the liver cannot uptake the drug from the delivery system and is not metabolized by the liver. Bortezomib is an anti-cancer drug. Due to its poor oral bioavailability, presystemic metabolism and decreased half-life, it was chosen to formulate as the SLN system with the use of a 3-factor, 3-level Box–Behnken design, by hot homogenization followed by an ultrasonication method. Trimyristin (Dynasan-114), tripalmitin (Dynasan 116) and tristearin (Dynasan-118) were used as lipids and based on the results from the initial studies tripalmitin (Dynasan116) was selected as the lipid for the further studies along with phosphatidylcholine as surfactant and Poloxamer 188 as stabilizer. The optimized formulation (F1) was obtained with minimum particle size (204 nm), maximum entrapment efficiency (70.24) and drug loading (21.24). The optimised batches were further investigated by FTIR, DSC, XRD, SEM and stability. In vitro release studies showed that maximum cumulative drug release was obtained for F1 (99.74%). The optimized formulation Bortezomib followed zero-order release kinetics with a strong correlation coefficient (R2= 0.9994). The nanoformulation prepared under optimized conditions is in concurrence with the expected results. It is concluded that the SLN formulation can be used as a potential carrier for the effective delivery of Bortezomib.

scholarly journals Chitosan inserts for periodontitis: Influence of drug loading, plasticizer and crosslinking on in vitro metronidazole release

2007 ◽  
Vol 57 (4) ◽  
pp. 469-477 ◽  
Author(s):  
Romi Barat ◽  
Anegundha Srinatha ◽  
Jayanta Pandit ◽  
Shampa Anupurba ◽  
Neelam Mittal
Keyword(s):  
Drug Release ◽  
Release Kinetics ◽  
Drug Loading ◽  
Dissolution Time ◽  
Cross Linking ◽  
Burst Release ◽  
Casting Method ◽  
The Mean ◽  
Polymer Ratio

Chitosan inserts for periodontitis: Influence of drug loading, plasticizer and crosslinking onin vitrometronidazole releaseChitosan based metronidazole (MZ) inserts were fabricated by the casting method and characterized with respect to mass and thickness uniformity, metronidazole loading andin vitrometronidazole release kinetics. The fabricated inserts exhibited satisfactory physical characteristics. The mass of inserts was in the range of 5.63 ± 0.42 to 6.04 ± 0.89 mg. The thickness ranged from 0.46 ± 0.06 to 0.49 ± 0.08 mm. Metronidazole loading was in the range of 0.98 ± 0.09 to 1.07 ± 0.07 mg except for batch CM3 with MZ loading of 2.01 ± 0.08 mg. The inserts exhibited an initial burst release at the end of 24 h, irrespective of the drug to polymer ratio, plasticizer content or cross-linking. However, further drug release was sustained over the next 6 days. Cross-linking with 10% (m/m) of glutaraldehyde inhibited the burst release by ~30% and increased the mean dissolution time (MDT) from 0.67 to 8.59 days. The decrease in drug release was a result of reduced permeability of chitosan due to cross-linking.

Sign in / Sign up

Export Citation Format

Share Document