Transforming sustained release into on-demand release: self-healing guanosine–borate supramolecular hydrogels with multiple responsiveness for Acyclovir delivery

2020 ◽  
Vol 8 (22) ◽  
pp. 6190-6203
Author(s):  
Cheng-guang Wu ◽  
Xiang Wang ◽  
Yun-feng Shi ◽  
Bin-cheng Wang ◽  
Wei Xue ◽  
...  

Supramolecular hydrogels derived from natural nucleoside have promising applications for on-demand drug release with controlled on/off switch and adjustable release kinetics in response to various stimuli.

1970 ◽  
Vol 8 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Mohammad Nezab Uddin ◽  
Ishtiaq Ahmed ◽  
Monzurul Amin Roni ◽  
Muhammad Rashedul Islam ◽  
Mohammad Habibur Rahman ◽  
...  

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)


2018 ◽  
Vol 8 (5) ◽  
pp. 465-474
Author(s):  
S PADMA PRIYA ◽  
AN Rajalakshmi ◽  
P Ilaveni

Objective: The objective of this research work is to develop and evaluate mucoadhesive microspheres of an anti-migraine drug for sustained release. Materials and Methods:  Mucoadhesive microspheres were prepared by emulsification method using Sodium alginate (SA), polyvinyl pyrrolidone (PVP) and Chitosan in the various drug-polymer ratios of 1:1, 1:2 and 1:3. Nine  formulations were formulated and  evaluated for  possible drug polymer interactions, percentage yield, micromeritic properties, particle size, drug content, drug entrapment efficiency, drug loading, swelling index, In-vitro wash off test, in vitro  drug release, surface morphology and release kinetics. Results: The results showed that no significant drug polymer interaction in FTIR studies. Among all the formulations SF3 containing sodium alginate showed 77.18% drug release in 6hrs. Conclusion: Amongst the developed mucoadhesive microspheres, SF3 formulation containing sodium alginate exhibited slow and sustained release in a controlled manner and it is a promising formulation for sustained release of Sumatriptan succinate. Keywords: Mucoadhesive microspheres, Sodium alginate, polyvinyl pyrrolidone, Chitosan, sustained release.


2012 ◽  
Vol 48 (4) ◽  
pp. 621-628 ◽  
Author(s):  
Shahid Sarwar ◽  
Mohammad Salim Hossain

The present study was undertaken to develop sustained release (SR) matrix tablets of losartan potassium, an angiotensin-II antagonist for the treatment of hypertension. The tablets were prepared by direct compression method, along with Kollidon SR as release retardant polymer. The amount of losartan potassium remains fixed (100 mg) for all the three formulations whereas the amounts of Kollidon SR were 250 mg, 225 mg, and 200 mg for F-1, F-2, and F-3 respectively. The evaluation involves three stages: the micromeritic properties evaluation of granules, physical property studies of tablets, and in-vitro release kinetics studies. The USP apparatus type II was selected to perform the dissolution test, and the dissolution medium was 900 mL phosphate buffer pH 6.8. The test was carried out at 75 rpm, and the temperature was maintained at 37 ºC ± 0.5 ºC. The release kinetics was analyzed using several kinetics models. Higher polymeric content in the matrix decreased the release rate of drug. At lower polymeric level, the rate and extent of drug release were enhanced. All the formulations followed Higuchi release kinetics where the Regression co-efficient (R²) values are 0.958, 0.944, and 0.920 for F-1, F-2, and F-3 respectively, and they exhibited diffusion dominated drug release. Statistically significant (P<0.05) differences were found among the drug release profile from different level of polymeric matrices. The release mechanism changed from non-fickian (n=0.489 for F-1) to fickian (n=0.439 and 0.429 for F-2, and F-3 respectively) as a function of decreasing the polymer concentration. The Mean Dissolution Time (MDT) values were increased with the increase in polymer concentration.


1970 ◽  
Vol 2 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Abul Kalam Lutful Kabir ◽  
Tasbira Jesmeen ◽  
Md Mesbah Uddin Talukder ◽  
Abu Taher Md Rajib ◽  
DM Mizanur Rahman

Commercially available four national and four international brands of esomeprazole magnesium sustained release matrix tablets were studied in simulated gastric medium (pH 1.2) for 2 hours and simulated intestinal medium (pH 6.8) for 8 hours time period using USP reference dissolution apparatus. All the national and international brands complied with the USP in-vitro dissolution specifications for drug release in simulated gastric medium. However, one of the national brands (Code: MP-1) and one of the international brands (MP-7) failed to fulfill the official requirement of 80% drug release within 8th hour in simulated intestinal medium. Drug release of that national and international brand were 70.49% and 67.05% respectively within the specified time period, however one national brand (Code: MP-4) released 103.46 % drug within 8th hour in intestinal medium. Drug release profiles were analyzed for zero order, first order and Higuchi equation to reveal the release kinetics perspective of esomeprazole magnesium sustained release matrix tablets. It was found that zero order release kinetics was the predominant release mechanism than first order and Higuchi release kinetics for those brands (Code: MP-2, MP-3, MP-4, MP-5, MP-6 and MP-8) which complied with the USP in vitro dissolution specification for drug releases. On the other hand, first order release kinetics was predominant for one national and also one international non compliant brands (Code: MP-1 and MP-6). Key Words: In vitro dissolution; Sustained release; Market preparations; Kinetic analysis; Esomeprazole; National brand; International brand. DOI: 10.3329/sjps.v2i1.5812Stamford Journal of Pharmaceutical Sciences Vol.2(1) 2009: 27-31


Author(s):  
P. Amsa ◽  
G. K. Mathan ◽  
S. Magibalan ◽  
E. K. Velliyangiri ◽  
T. Kalaivani ◽  
...  

The major goal of this study was to develop and evaluate Sustained release matrix tablets of Gabapentin with Hibiscus rosa - sinensis leaves mucilage prepared by using wet granulation technique with microcrystalline cellulose as a diluents and magnesium stearate as a lubricant. Pre-compression and post-compression evaluation of physicochemical parameters were carried out and to be within acceptable limits. Drug and polymer compatibility were validated by FTIR measurements. Further, tablets were evaluated for in vitro release study. To get the sustained release of Gabapentin, the concentration of Hibiscus rosa- sinensis mucilage was tuned with a gas-generating agent. The % drug release of all formulation from F1 to F5 showed 91.24%, 80.24%, 70.53%, 62.12% and 49.83% respectively. All the dosage form release kinetics was computed using zero order, first order, Higuchi, and Korsmeyer–Peppas methods. From the above results, it is concluded that the n value of formulation F5 showed 0.78 suggesting anomalous (non-fickian) behavior of the drug. Mucilage from the leaves of Hibiscus rosa-sinensis has a great retarding effect in drug release from sustained release tablets.


2021 ◽  
Vol 11 (2) ◽  
pp. 31-37
Author(s):  
Mehak Siddiqui ◽  
L. K. Omray ◽  
Pushpendra Soni

The overall objective of the present work was to develop an oral sustained-release (SR) Metformin tablet that is prepared by the direct compression method by using hydrophilic hydroxyl propyl methyl cellulose (HPMC) and Guar gum polymer alone as well as in combination at different concentrations. Metformin is a biguanide that has a relatively short plasma half-life. It has low absolute bioavailability. All the properties were evaluated for thickness, weight variation, hardness and drug content uniformity and in vitro drug release. The mean dissolution time is used to characterize the drug release rate from a dosage form that indicates the drug release-retarding efficiency of the polymer. The hydrophilic matrix of HPMC alone could not control the Metformin release effectively for 12 h but when combined with Guar gum, it could slow down the release of drug and, thus, can be successfully employed for formulating Sustain Release matrix tablets. Keywords: Guar gum, hydroxylpropylmethylcellulose, matrix tablets, release kinetics,


Author(s):  
AHMED M AGIBA ◽  
WAGEEH ABDEL HAKEEM ◽  
ASHRAF G ZAYED

Objective: Ranolazine (RZ), antianginal drug indicated for the treatment of chronic stable angina pectoris, was formulated into sustained-release matrix tablets and optimized to improve patient compliance and achieve controlled release over a certain period. Methods: Different formulations were prepared by wet- and melt-granulation techniques. Excipients at different ratios as Eudragit® L100-55, Methocel™ E5, Avicel® PH-101, and carnauba wax powder were used to develop a ternary polymeric matrix system for the controlled delivery of RZ. The prepared formulations were subjected to granulometric and characteristic studies. Comparative dissolution and release kinetic studies of the selected formulation and the reference product, Ranexa® extended-release film-coated tablets, Gilead Sciences, Inc., USA, were further carried out to ensure product similarity. Results: The optimum pH-dependent to pH-independent polymers ratio was 1:1.3 (w/w). Extragranular carnauba wax in a concentration of 32.50 mg/tablet (2.50 gm% w/w) was the key excipient in controlling drug release kinetics by forming waxy matrix granules which prevent rapid dissolution. Modulation of the microenvironmental pH using a potent alkalinizing agent was very effective for controlling drug release patterns in different dissolution media from pH 1.2–6.8. Conclusion: The release of RZ from the matrix tablets was controlled for a period of 24 h, and thereby expected to provide patient compliance with minimal side effects.


1970 ◽  
Vol 8 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Abul Kalam Lutful Kabir ◽  
Bishyajit Kumar Biswas ◽  
Abu Shara Shasur Rouf

The objective of this study was to develop a sustained release matrix tablet of aceclofenac usinghydroxypropyl methylcellulose (HPMC K15M and HPMC K100M CR) in various proportions as release controllingfactor by direct compression method. The powders for tableting were evaluated for angle of repose, loose bulkdensity, tapped bulk density, compressibility index, total porosity and drug content etc. The tablets were subjected tothickness, weight variation test, drug content, hardness, friability and in vitro release studies. The in vitro dissolutionstudy was carried out for 24 hours using United States Pharmacopoeia (USP) 22 paddle-type dissolution apparatus inphosphate buffer (pH 7.4). The granules showed satisfactory flow properties, compressibility index and drug contentetc. All the tablets complied with pharmacopoeial specifications. The results of dissolution studies indicated that theformulations F-2 and F-3 could extend the drug release up to 24 hours. By comparing the dissolution profiles with themarketed product, it revealed that the formulations exhibited similar drug release profile. From this study, a decreasein release kinetics of the drug was observed when the polymer concentration was increased. Kinetic modeling of invitro dissolution profiles revealed the drug release mechanism ranges from diffusion controlled or Fickian transport toanomalous type or non-Fickian transport, which was only dependent on the type and amount of polymer used. Thedrug release followed both diffusion and erosion mechanism in all cases. The drug release from these formulationswas satisfactory after 3 months storage in 40°C and 75% RH. Besides, this study explored the optimum concentrationand effect of polymer(s) on acelofenac release pattern from the tablet matrix for 24 hour period.Key words: Aceclofenac; sustained release; hydrophillic matrix; HPMC; direct compression.DOI: 10.3329/dujps.v8i1.5332Dhaka Univ. J. Pharm. Sci. 8(1): 23-30, 2009 (June)


2013 ◽  
Vol 11 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Monnujan Nargis ◽  
Md Saiful Islam ◽  
Fatima Naushin ◽  
Syed Shabbir Haider

Sustained release formulations of metoclopramide HCl (4-amino-5-chloro-N-(2-diethylaminoethyl)-2- methoxybenzamide hydrochloride) (MH) were prepared using carnauba wax (CW) and stearic acid (SA) as matrix formers. Granules were prepared by melt granulation method while direct compression technique was used to prepare the tablets. The drug release profiles of these products were studied by in-vitro dissolution testing in simulated gastric, gastrointestinal and intestinal media of pH 1.2, 4.5 and 7.5, respectively. The increase in the proportion of SA in the granules produced a concomitant decrease of the initial drug release rate but later on the release rate was enhanced in the intestinal medium. Drug release was found to be affected by compression force and stirring rate but also showed a dependency on pH of the dissolution fluid. The fastest release rate was found at pH 4.5 and the slowest at pH 1.2 which was consistent with the drug’s solubility behavior. Matrix erosion and water uptake rates were highest in the intestinal medium and lowest in the gastric medium. The drug release kinetics followed the Higuchi’s model in all cases. DOI: http://dx.doi.org/10.3329/dujps.v11i2.14563 Dhaka Univ. J. Pharm. Sci. 11(2): 129-136, 2012 (December)


2020 ◽  
Vol 3 (3) ◽  
pp. 197-211
Author(s):  
Kuldeep H. Ramteke ◽  
Dipika E. Ghadge ◽  
Savita A. Palve ◽  
Sachin S. Gaikwad

Background: Tablets being the conventional dosage forms can be modified for providing the desired therapeutic effect to the patients. The network of matrix in the tablet allows the drug release to be slowed down considerably. Objective: The prime objective of the study was to formulate sustained release glibenclamide matrix tablets using locust bean gum and karaya gum as a matrix polymer. Methods: Tablets were formulated by optimization using 32 factorial designs by direct compression method using different drug: polymer concentrations. The dependent variables selected were % cumulative drug release (Y1) and % drug content (Y2). The independent variables are the amount of locust bean gum (X1) and karayagum (X2). Drug-polymer compatibility studies were confirmed by FTIR and DSC. The pre-compression properties of powder were assessed indicating a good flow property. The evaluation results of the tablets were found to be within the Indian Pharmacopoeial limit. In this work, the effect of diluents type and polymer type was studied on the drug release with its increase in concentration. Results: All the formulations showed retarded drug release as the concentration of the polymer was increased. Formulation F8 was selected as the best-optimized formulation with about 100.56% drug release within 12 h. Release kinetics was carried out and it was found to be zero-order release and from assay, drug content was found to be in limits. Conclusion: ANOVA analysis indicated that the studied variables affected the response variables significantly. The optimized formulation was stable. Hence, it is concluded that the Glibenclamide sustained release matrix tablet containing natural polymers were successfully formulated by using 32 factorial design.


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