scholarly journals Investigation of the Dissolution Characteristics of Nifedipine Extended-Release Formulations Using USP Apparatus 2 and a Novel Dissolution Apparatus

2009 ◽  
Vol 16 (2) ◽  
pp. 6-13 ◽  
Author(s):  
Grzegorz Garbacz ◽  
Henning Blume ◽  
Werner Weitschies
Keyword(s):  
Extended Release ◽  
Dissolution Apparatus ◽  
Usp Apparatus ◽  
Usp Apparatus 2 ◽  
Extended Release Formulations

scholarly journals DISSOLUTION BEHAVIOR OF CARBAMAZEPINE SUSPENSIONS USING THE USP DISSOLUTION APPARATUS 2 AND THE FLOW-THROUGH CELL METHOD WITH SIMULATED GI FLUIDS

2017 ◽  
Vol 9 (10) ◽  
pp. 111
Author(s):  
Jose Raul Medina ◽  
Erik Aguilar ◽  
Marcela Hurtado
Keyword(s):  
Laminar Flow ◽  
Simulated Gastric Fluid ◽  
Cell Method ◽  
Drug Products ◽  
Flow Through ◽  
Model Independent ◽  
Dissolution Apparatus ◽  
Usp Apparatus ◽  
Usp Apparatus 2 ◽  
Independent Parameters

Objective: To characterize the dissolution behaviour of carbamazepine generic suspensions using the USP Dissolution Apparatus 2 and the flow-through cell method with simulated gastrointestinal fluids as dissolution media.Methods: Tegretol® suspension and two generic formulations were tested. Dissolution studies were performed using the USP Apparatus 2 (75 rpm and 900 ml of dissolution medium) and the flow-through cell method (laminar flow at 16 ml/min). Simulated gastric fluid (SGF) (with and without pepsin) and simulated intestinal fluid (SIF) (without pancreatin) at 37.0±0.5 °C, was used as dissolution media. The quantity of dissolved carbamazepine was determined at 5 min intervals until reaching 60 min, at 285 nm. Percentage dissolved at 60 min, mean dissolution time, dissolution efficiency values (model-independent parameters), as well as t50% and t63.2% were calculated (model-dependent parameters). Values for all parameters were compared between the reference and generic formulations using one-way analysis of variance (ANOVA) following a Dunnett’s multiple comparison test. Dissolution data were also fitted to different fit models.Results: Since the first sampling time, the reference product had reached 100% of drug dissolved, which was determined using USP Apparatus 2. Nevertheless, significant differences in the three model-independent parameters of generic products were found (*P<0.05). Dissolution data obtained with the paddle apparatus were fitted to different kinetic equations; however, using the flow-through cell method and SIF without pancreatin, the three drug products were fitted to the same kinetic model (Gompertz). With ANOVA-based comparisons and the flow-through cell method, significant differences were found in dissolution data of generic product A versus reference at all sampling times (*P<0.05). The flow-through cell method and SGF with pepsin were the best options to discriminate among dissolution profiles.Conclusion: The flow-through cell method seems to be an adequate dissolution apparatus to characterize in vitrodissolution performance of Class II drugs manufactured as suspensions. For carbamazepine suspensions, SGF and laminar flow at 16 ml/min were the most appropriate conditions to discriminate among generic formulations. Given the physicochemical characteristics of carbamazepine and the environment in which the drug products were tested, these differences could be of clinical relevance. 

scholarly journals IN VITRO EQUIVALENCE STUDY OF DIFFERENT DOSES OF CARBAMAZEPINE REFERENCE TABLETS USING USP APPARATUSES 2 AND 4

2019 ◽  
pp. 291-295
Author(s):  
JOSE RAUL MEDINA-LOPEZ ◽  
Luis Antonio Cedillo-Díaz ◽  
Marcela Hurtado
Keyword(s):  
High Dose ◽  
Local Market ◽  
Dissolution Medium ◽  
Usp 4 ◽  
Usp Apparatus 4 ◽  
Dissolution Apparatus ◽  
Usp Apparatus ◽  
Usp Apparatus 2

Objective: To perform an in vitro equivalence study of two doses of carbamazepine reference tablets sold in the local market under hydrodynamic conditions of USP Apparatus 4, a dissolution apparatus that better simulates the human gastrointestinal tract. Results were compared with dissolution official conditions using USP Apparatus 2. Methods: Dissolution profiles of both formulations were carried out with an automated USP Apparatus 2 at 75 rpm and 900 ml of dissolution medium. USP Apparatus 4 with laminar flow at 16 ml/min and 22.6 mm cells were used. 1% lauryl sulfate aqueous solution at 37.0±0.5 °C was used as dissolution medium. Spectrophotometric determination of drug at 285 nm was carried out during 60 min. Dissolution profiles were compared with model-independent and-dependent approaches. Results: When comparing dissolution profiles of low vs. high dose similar profiles were found (f2>50) in each dissolution apparatus, however, when the same dose was compared, USP 2 vs. USP 4, opposite results were obtained. Comparison of mean dissolution time and dissolution efficiency data corroborates these results. Weibull function was the best mathematical model that described the in vitro dissolution performance of carbamazepine. No significant differences were found in Td values (low vs. high dose) but opposite results were also found with USP 2 vs. USP 4. Conclusion: Equivalent dissolution performance of two doses of carbamazepine reference tablets were found in each USP dissolution apparatus. The main problem identified in this comparative study is the low dissolution rate and extent found with USP Apparatus 4. More research on this field is necessary for all available doses of reference drug products since the quality of generic formulations depends on the quality of references.

Formulation and In vitro Release Characterization of Metoprolol Succinate Extended Release Tablets

2012 ◽  
Vol 4 (4) ◽  
pp. 1537-1543
Author(s):  
Sakthikumar T ◽  
Rajendran N N ◽  
Natarajan R
Keyword(s):  
Drug Release ◽  
Extended Release ◽  
In Vitro Release ◽  
Methyl Cellulose ◽  
Wet Granulation ◽  
Direct Compression ◽  
Metoprolol Succinate ◽  
Extended Release Formulations ◽  
Vitro Release

The present study was aimed to develop an extended release tablet of metoprolol Succinate for the treatment of hypertension.  Four extended release formulations F1-F4 were developed using varying proportions of hydroxylpropyl-methylcellulose K100M, sodium carboxy methyl cellulose and Eudragit L30 D55 by wet granulation. Five extended release formulations F5-F9 containing HPMC K100M and HPMC 5 cps in varying concentration were developed by direct compression. The physicochemical and in vitro release characteristics of all the formulations were investigated and compared. Two formulations, F7 and F8 have shown not more 25% drug release  in 1st h, 20%-40% drug release at 4th hour, 40%-60% drug release at 8th hour and not less than 80% at 20th hour and the release pattern conform with USP specification for 24 hours extended release formulation. It can be conclusively stated that optimum concentration of HPMC K100M (58%-65%) by direct compression method can yield an extended release of metoprolol succinate for 24 hours.

Antibacterial glass-ionomer cement restorative materials: A critical review on the current status of extended release formulations

2017 ◽  
Vol 262 ◽  
pp. 317-328 ◽  
Author(s):  
Tahereh Mohammadi Hafshejani ◽  
Ali Zamanian ◽  
Jayarama Reddy Venugopal ◽  
Zahra Rezvani ◽  
Farshid Sefat ◽  
...  
Keyword(s):  
Critical Review ◽  
Extended Release ◽  
Glass Ionomer Cement ◽  
Current Status ◽  
Glass Ionomer ◽  
Restorative Materials ◽  
Extended Release Formulations ◽  
Ionomer Cement

Oral Extended-Release Formulations

2008 ◽  
pp. 1191-1222 ◽  
Author(s):  
Anette Larsson ◽  
Susanna Abrahmsn-Alami ◽  
Anne Juppo
Keyword(s):  
Extended Release ◽  
Extended Release Formulations

scholarly journals A Clinician's Guide to Oral Extended-Release Drug Delivery Systems in Epilepsy

2018 ◽  
Vol 23 (4) ◽  
pp. 277-292 ◽  
Author(s):  
James W. Wheless ◽  
Stephanie J. Phelps
Keyword(s):  
Adverse Effects ◽  
Extended Release ◽  
Extended Period ◽  
Immediate Release ◽  
Serum Drug Concentration ◽  
Neurologic Disorders ◽  
Dosing Regimens ◽  
Care Costs ◽  
Extended Release Formulations

Epilepsy is one of the most common chronic neurologic disorders that affects individuals of all ages. It is primarily managed with antiepileptic drugs (AEDs), with the goal of maintaining complete seizure control combined with minimal or no adverse effects. Oral administration is the mainstay of AED delivery for patients with chronic epilepsy and consists essentially of immediate-release (IR) and modified-release (delayed-release and extended-release [ER]) dosage formulations. Extended-release formulations (hydrophilic or hydrophobic matrix systems, reservoir systems, and osmotic-release systems) release a drug in a controlled manner during an extended period of time following administration. Extended-release formulations have many advantages compared with IR formulations, including simplification of dosing regimens, reduction in pill burden, and reduction in the peak-to-trough fluctuations in serum drug concentration that may be associated with a decreased risk of adverse effects and of seizures. These advantages have the potential to increase adherence to antiepileptic therapy, improve the quality of life of patients, and reduce health care costs. This article, which is intended as a practical guide for clinicians, reviews the properties of the different ER AED formulations currently available and discusses the advantages of ER over IR formulations. Subsequently, an explanation of the technologic basis of the different oral ER formulations, the critical attributes that differentiate ER products, and their individual strengths and weaknesses is provided. Specific recommendations to practitioners on treating patients with ER formulations are included.

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