Basic Physical Parameters of Polymeric Matrices Influencing Drug Release

1983 ◽  
pp. 201-211
Author(s):  
Fabio Carli
Author(s):  
Bhikshapathi D. V. R. N. ◽  
Haarika B ◽  
Jyothi Sri S ◽  
K Abbulu

The purpose of present investigation was to develop floating matrix tablets of gemifloxacin mesylate, which after oral administration could prolong the gastric residence time, increase the drug bioavailability and diminish the side effects of irritating drugs. Tablets containing drug, various viscosity grades of hydroxypropyl methylcellulose such as HPMC K4M and HPMC K15M as matrix forming agent, Sodium bicarbonate as gas-forming agent and different additives were tested for their usefulness in formulating gastric floating tablets by direct compression method. The physical parameters, in vitro buoyancy, release characteristics and in vivo radiographic study were investigated in this study. The gemifloxacin mesylate floating tablets were prepared using HPMC K4M polymer giving more sustained drug release than the tablet containing HPMC K15M. All these formulations showed floating lag time of 30 to 47 sec and total floating time more than 12 h. The drug release was decreased when polymer concentration increases and gas generating agent decreases. Formulation that contains maximum concen-tration of both HPMC K15M and sodium bicarbonate (F9) showing sufficiently sustained with 99.2% of drug release at 12 h. The drug release from optimized formulation follows Higuchi model that indicates the diffusion controlled release. The best formulation (F9) was selected based on in vitro characteristics and used in vivo radiographic studies by incorporating barium sulphate as a radio-opaque agent and the tablet remained in the stomach for about 6 h.   


Author(s):  
Y. Madhusudan Rao ◽  
Katakam V V ◽  
S Reddy ◽  
J M Somagoni ◽  
P K Panakanti ◽  
...  

The aim of this study was to prepare mini tablets to be filled into a capsule that is designed to float on the gastric contents based on gas formation technique. The drug-containing core mini-tablets were prepared by wet granulation method followed by a coating of the core units with seal coating, an effervescent layer and a gas-entrapping polymeric membrane (Eudragit RS30D, RL30D). Dipyridamole, which is predominantly absorbed in the upper part of GI tract and unabsorbed/insoluble at the lower intestine, was used as a model drug. The effect of the preparative parameters like amount of the effervescent agent layered onto the seal coated units, type and coating level of the gas-entrapping polymeric membrane, floating ability and drug release properties of the multiple-unit FDDS were evaluated. The formulations were evaluated for pharmacopoeial quality control tests. Physical parameters were found to be within the acceptable limits. The system using Eudragit® RL30D as a gas-entrapping polymeric membrane exhibited floating properties. The time to float decreased as amount of the effervescent agent increased and coating level of gas-entrapping polymeric membrane decreased. The optimum system exhibited complete floating within 3 minutes and maintained that buoyancy over a period of 8 hours. The drug release was sustained and linear with the square root of time. Increasing the coating level of the gas-entrapping polymeric membrane decreased drug release. Both the rapid-floating and sustained-release properties were achieved in the multiple-unit floating delivery system developed in this study. The in vivo gastric residence time was examined by radiograms and it was found that the units remained in the stomach for about 6 hours. The analysis of the dissolution data after storage at 40°C and 75% RH for 6 months showed no significant change indicating good stability.


2011 ◽  
Vol 61 (2) ◽  
pp. 217-226 ◽  
Author(s):  
Komuravelly Someshwar ◽  
Kalyani Chithaluru ◽  
Tadikonda Ramarao ◽  
K. Kumar

Formulation and evaluation of effervescent floating tablets of tizanidine hydrochloride Tizanidine hydrochloride is an orally administered prokinetic agent that facilitates or restores motility through-out the length of the gastrointestinal tract. The objective of the present investigation was to develop effervescent floating matrix tablets of tizanidine hydrochloride for prolongation of gastric residence time in order to overcome its low bioavailability (34-40 %) and short biological half life (4.2 h). Tablets were prepared by the direct compression method, using different viscosity grades of hydroxypropyl methylcellulose (HPMC K4M, K15M and K100M). Tablets were evaluated for various physical parameters and floating properties. Further, tablets were studied for in vitro drug release characteristics in 12 hours. Drug release from effervescent floating matrix tablets was sustained over 12 h with buoyant properties. DSC study revealed that there is no drug excipient interaction. Based on the release kinetics, all formulations best fitted the Higuchi, first-order model and non-Fickian as the mechanism of drug release. Optimized formulation (F9) was selected based on the similarity factor (f2) (74.2), dissolution efficiency at 2, 6 and 8 h, and t50 (5.4 h) and was used in radiographic studies by incorporating BaSO4. In vivo X-ray studies in human volunteers showed that the mean gastric residence time was 6.2 ± 0.2 h.


2021 ◽  
Vol 99 ◽  
pp. 257-269
Author(s):  
J.S. Borges ◽  
J.A. Ferreira ◽  
G. Romanazzi ◽  
E. Abreu

INDIAN DRUGS ◽  
2012 ◽  
Vol 49 (12) ◽  
pp. 29-35
Author(s):  
N.G.N Swamy ◽  
◽  
P Shilpa ◽  
Z. Abbas

Chewing gums are mobile drug delivery systems, with a potential for administering drugs either for local action or for systemic absorption via buccal route. Dextromethorphan hydrobromide chewing gum formulations were made employing Pharmagum M as the base with an aim to overcome the firstpass effect, reducing the risk of overdosing, ease of administration and for achieving faster systemic absorption. Dextromethorphan hydrobromide was further transformed into spray dried form and incorporated into Pharmagum M base with the object of solubility enhancement and masking the bitter taste of the drug. The prepared medicated chewing gums were evaluated for various precompression and postcompression parameters. The in vitro drug release profiles were carried out employing Erweka DRT chewing apparatus. It was observed that increasing the chewing gum base concentration resulted in a decreased drug release profile. The drug in the spray dried form revealed improved performance in comparison to the directly contained drug. The drug release data were fitted into various kinetic models. It was observed that the drug release was matrix diffusion controlled and revealed a non-Fickian drug release mechanism. Accelerated stability studies were carried out on select formulations as per ICH guidelines. The formulations were found to be stable in respect to physical parameters and no significant deviations were seen in respect to in vitro drug release characteristics.


2019 ◽  
Vol 9 (4) ◽  
pp. 574-578
Author(s):  
Mohammad Faizan Mohammad Gufran ◽  
Sailesh Kumar Ghatuary ◽  
Reena Shende ◽  
Prabhat Kumar Jain ◽  
Geeta Parkhe

Formulation development is an important part of drug design and development. Bioavailability and bioequivalence are totally dependent on formulation development. Now-a-days formulation development is done by following QbD (Quality by Design).The aim of present study is to formulate Gemfibrozil (Gem) sustained release (SR) and immediate release (IR) bilayer tablet by different concentration of Hydroxypropyl methylcellulose (HPMC) and HPMC K 100 M to control the release pattern. The sustained release layer of Gem was prepared by using different grades of HPMC like, HPMC K-15, HPMC K-4 along with other excipients by direct compression technique. The immediate release layer of Gem was prepared by Cross carmellose sodium, Crospovidone and Sodium starch glycolate by direct compression technique. The powders were evaluated for their flow properties and the finished tablets were evaluated for their physical parameters. The both immediate release and sustained release layers of Gem were characterized by FT-IR and in vitro dissolution studies. The drug release study of Gem was evaluated using USP-II paddle type dissolution apparatus. The release rate of Gem in immediate release layer was studied for 15 min in 0.1 N HCL media and that of Gem in sustained release layer was studied for 12 h in 0.1 N HCL. From the nine batches F6 batch showed good release behaviour 99.85% of drug is released over 12 hours. Gem belongs to BCS Class II (log P 3.6) with poor solubility and high permeability resulting in limited and variable bioavailability. Total four trial batches of each drug have been manufactured to optimize and develop a robust and stable formulation, the stability studies of the products also comply with ICH guideline. Keywords: Bilayer floating tablets, Gemfibrozil, Biphasic drug release, HPMC K 15.


INDIAN DRUGS ◽  
2016 ◽  
Vol 53 (10) ◽  
pp. 27-33
Author(s):  
B. P. Patel ◽  
◽  
D. M. Patel

Upper respiratory tract infections (URTIs) are illnesses caused by an acute infection which involves the upper respiratory tract: nose, sinuses, pharynx or larynx. Roxithromycin (macrolide antibiotic) and ambroxol HCl (mucolytic) are used for this treatment. The dual release system of roxythromycin and ambroxol HCl was successfully prepared by bi-layer tablet approach for management of URTI. Quick release of roxithromycin was achieved by using disintegrants and slow release of ambroxol HCl was achieved by using matrix formulation of drug with HPMC K4M and ethyl cellulose. The 32 full factorial design was adopted for optimization of polymer concentration to achieve identical drug release with theoretical dissolution profile. The amount of HPMC K4M and ethyl cellulose were selected as independent variable and the similarity factor with theoretical dissolution profile and percentage drug release at 10th hr was selected as dependent variables. The prepared dual release tablets were evaluated for physical parameters, drug content, in vitro drug release study, etc. All the parameters were found to be acceptable in range. As the concentration of HPMC K4M is increased, the drug release decreases and the effect of ethyl cellulose was found to be less compared to HPMC K4M.


Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 852 ◽  
Author(s):  
Stavroula Nanaki ◽  
Athina Viziridou ◽  
Alexandra Zamboulis ◽  
Margaritis Kostoglou ◽  
Georgios Z. Papageorgiou ◽  
...  

In the present study, novel block copolymers of poly(l-lactide)-block-poly(propylene adipate) (PLLA-b-PPAd) were synthesized in two ratios, 90/10 and 75/25 w/w and were further investigated as long-acting injectable (LAI) polymeric matrices in naltrexone base microparticle formulations. The synthesized polymers were characterized by 1H-NMR, 13C-NMR, FTIR, XRD, TGA and DSC. NMR and FTIR spectroscopies confirmed the successful synthesis of copolymers while DSC showed that these are block copolymers with well-defined and separated blocks. Microparticles were prepared by single emulsification method and were further characterized. Nanoparticles in the range of 0.4–4.5 μm were prepared as indicated by SEM, with copolymers giving the lowest particle size. By XRD and DSC it was found that naltrexone was present in the amorphous state in its microparticles. Dissolution study showed a drug release extending over seven days, indicating that these novel PLLA-b-PPAd copolymers could be promising matrices for naltrexone’s LAI formulations. It was evidenced that drug release depended on the copolymer composition. Model release studies showed that drug release is controlled by diffusion.


Author(s):  
B. Valli Manalan ◽  
Nadendla Swathi ◽  
Narra Nandini ◽  
N. Hari Sree ◽  
Nilla Tejaswi Sai Maha Lakshmi ◽  
...  

The aim of the present study was to design an oral sustained release matrix tablet of highly water soluble biguanide anti diabetic drug. The matrix tablets are prepared by melt granulation method using HPMC K 200M as hydrophilic drug release retarding polymer, and stearic acid as melt able binder as well as hydrophobic carrier. The drug and excipients compatibility was studied by FT – IR. The formulated matrix tablets were characterized for physical parameters and in vitro dissolution profile. FT – IR spectra revealed the absence of drug excipients interaction. The physical parameters of the tablets were found within the limits. The drug release kinetics demonstrated that by increasing the concentration of hydrophilic polymer and hydrophobic carrier the drug release rate was retarded proportionally. Kinetic modelling of in vitro release profile revealing that the drug release from the matrix tablets following first order kinetics, and the drug release mechanism of optimized (F7) formula following non fickian transport mechanism. Accelerated stability studies were performed according to ICH guide lines. Temperature 40±20 c and relative humidity 75±5% RH to study physical and chemical changes of formulation. No physical or chemical changes were observed after t accelerated stability studies.


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