Mechanical strength and gastric residence time of expandable fibrous dosage forms

Presently, various approaches have been exploited in the prolongation of gastric residence time which includes floating drug delivery system (FDDS), swelling and expanding systems, bio-adhesive systems, modified shape systems and high density systems. Among various methods, floating drug delivery system is considered to be a predominant method. Gastric emptying of dosage forms is an extremely varying process and ability to extend and control the emptying time is a valuable resource for the dosage forms. This FDDS is having the ability to provides a solution for this purpose. The FDDS is a bulk density system lower than the gastric fluid, so that the rest will float on the stomach contents for a prolonged period of time and allowing the drug to release slowly at a desired rate from the system and intensifies the bio-availability of the drug having narrow absorption window. The main intension of writing this review on floating drug delivery system is to study the mechanism of flotation to acheive the gastric retention and to discuss briefly about the background of FDDS, advantages and disadvantages, application of FDDS and factors affecting the gastric retension time.

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Pharmaceutical Formulations to Increase Gastric Residence Time: Concepts and Strategies

Drug Delivery Letters ◽

10.2174/2210303107666170428102247 ◽

2017 ◽

Vol 7 (3) ◽

Author(s):

Praveen Radhakrishnan ◽

Sandeep K. Singh ◽

Priya R.P. Verma

Keyword(s):

Residence Time ◽

Pharmaceutical Formulations ◽

Gastric Residence Time ◽

Time Concepts

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Formulation and evaluation of effervescent floating tablets of tizanidine hydrochloride

Acta Pharmaceutica ◽

10.2478/v10007-011-0015-5 ◽

2011 ◽

Vol 61 (2) ◽

pp. 217-226 ◽

Cited By ~ 7

Author(s):

Komuravelly Someshwar ◽

Kalyani Chithaluru ◽

Tadikonda Ramarao ◽

K. Kumar

Keyword(s):

Drug Release ◽

Residence Time ◽

Release Kinetics ◽

Hydroxypropyl Methylcellulose ◽

Matrix Tablets ◽

Physical Parameters ◽

Floating Tablets ◽

Gastric Residence Time

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.

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DESIGN AND CHARACTERIZATION OF ALFUZOSIN HCL GASTRORETENTIVE FLOATING MATRIX TABLETS EMPLOYING HPMC K 100M

INDIAN DRUGS ◽

10.53879/id.55.11.10741 ◽

2018 ◽

Vol 55 (11) ◽

pp. 71-73

Author(s):

Ch. Taraka Ramarao ◽

◽

J Vijaya Ratna ◽

R. B. Srinivasa

Keyword(s):

Drug Release ◽

Dosage Forms ◽

Matrix Tablets ◽

Fickian Diffusion ◽

Release Mechanism ◽

Gastric Residence Time ◽

Drug Release Mechanism ◽

The Matrix ◽

Gastro Retentive

The present investigation involves developing gastro retentive drug delivery systems (GFDDS) of alfuzosin HCl using HPMCK100M a is the matrixing agent and floating enhancer. Sodium bicarbonate in the acidic environment reacts with the acid and produces carbon dioxide. The gastro retentive tablets can be formulated to increase the gastric residence time and thereby increase the oral bioavailability. From the drug release study, it was concluded that the AFTB4 formula of HPMC K 100 M matrix tablets gives the controlled release up to 12 hours by showing increased release with floating lag time 24 seconds. Non – Fickian diffusion was the drug release mechanism from the matrix tablets formulated employing HPMC K 100 M. The matrix tablets (AFTB4) formulated employing 40 % HPMC K 100 M are best suited to be used for gastro retentive dosage form of alfuzosin HCl. Finally, it can be concluded that good candidates for the preparation of gastro retentive dosage forms due its gastric stability, gastric absorption and better bioavailability.

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REVIEW ON GASTRORETENTIVE DRUG DELIVERY SYSTEM

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2020.v13i12.37264 ◽

2020 ◽

pp. 38-45

Author(s):

MANDAR J BHANDWALKAR ◽

PRASAD S DUBAL ◽

AKASH K.TUPE ◽

SUPRIYA N MANDRUPKAR

Keyword(s):

Drug Delivery ◽

Small Intestine ◽

Drug Delivery System ◽

Residence Time ◽

Delivery System ◽

Oral Drug Delivery ◽

Dosage Forms ◽

Oral Dosage ◽

Oral Drug ◽

Low Solubility

In recent years, gastroretentive drug delivery system (GRDDS) has gained researcher’s interest in the field of oral drug delivery. Various GRDDS approaches can be utilized to retain the dosage forms in the stomach and to release the drug slowly for an extended period of time. GRDDS can be used to prolong the residence time of delivery system in the stomach. This results in targeting of drug release at a specific site for the systemic or local effects. GRDDS can be used to overcome challenges associated with conventional oral dosage forms and to release the drug at a specific absorption site to improve bioavailability of particular drug substance. The challenges include fast gastric emptying of the dosage form which results in the poor bioavailability of the drug. Prolongation of the retention of drugs in stomach those having low solubility at high intestinal pH improves the solubility of drugs. GRDDS has proved to be effective in systemic actions as well as in local actions to treat gastric or duodenal ulcers. Local activity in the upper part of the small intestine can be obtained by improving the residence time of delivery system in the stomach. The system is useful for drugs which are unstable in the intestine or having a low solubility/permeability in the small intestine. Various GRDDS approaches include high density (sinking) systems, low-density (floating systems), mucoadhesive, expandable, unfoldable, superporous hydrogel systems, and magnetic systems.

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Patterned nanofiber air filters with high optical transparency, robust mechanical strength, and effective PM2.5 capture capability

RSC Advances ◽

10.1039/d0ra01967d ◽

2020 ◽

Vol 10 (34) ◽

pp. 20155-20161 ◽

Cited By ~ 3

Author(s):

Jinshan Cao ◽

Zhiqiang Cheng ◽

Lijuan Kang ◽

Meng Lin ◽

Lihao Han

Keyword(s):

Particle Size ◽

Mechanical Strength ◽

Human Health ◽

Residence Time ◽

Small Particle ◽

Toxic Substances ◽

Small Particle Size ◽

Daily Production ◽

Air Filters ◽

Strong Activity

PM2.5, due to its small particle size, strong activity, ease of the attachment of toxic substances and long residence time in the atmosphere, has a great impact on human health and daily production.

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