Evaluation of peroral silicone dosage forms in humans by gamma-scintigraphy

Kedzierewicz, F.; Thouvénot, Pierre; Lemut, Josiane; Etienne, A.; Hoffman, Maurice; Maincent, Philippe

doi:10.1016/s0168-3659(98)00154-0

Cited by 76 publications

(48 citation statements)

References 17 publications

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“…A controlled drug delivery system with prolonged residence time in the stomach is of particular interest for drugs that (1) are locally active in the stomach, (2) have an absorption window in the stomach or in the upper small intestine, (3) are unstable in the intestinal or colonic environment, and (4) exhibit low solubility at high pH values (2). The controlled gastric retention of solid dosage forms may be achieved by the mechanisms of mucoadhesion (3), flotation (4), sedimentation (5), expansion (6,7), modified shape systems (8,9), or by the simultaneous administration of pharmacological agents (10) that delay gastric emptying.…”

Section: Introductionmentioning

confidence: 99%

Development and In Vivo Floating Behavior of Verapamil HCl Intragastric Floating Tablets

et al. 2009

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Abstract. A novel gastro retentive controlled release drug delivery system of verapamil HCl was formulated in an effort to increase the gastric retention time of the dosage form and to control drug release. Hydroxypropylmethylcellulose (HPMC), carbopol, and xanthan gum were incorporated for gelforming properties. Buoyancy was achieved by adding an effervescent mixture of sodium bicarbonate and anhydrous citric acid. In vitro drug release studies were performed, and drug release kinetics was evaluated using the linear regression method. The optimized intragastric floating tablet composed of 3:2 of HPMC K4M to xanthan gum exhibited 95.39% drug release in 24 h in vitro, while the buoyancy lag time was 36.2 s, and the intragastric floating tablet remained buoyant for >24 h. Zero-order and nonFickian release transport was confirmed as the drug release mechanism from the optimized formulation (F7). X-ray studies showed that total buoyancy time was able to delay the gastric emptying of verapamil HCl intragastric floating tablet in mongrel dogs for more than 4 h. Optimized intragastric floating tablet showed no significant change in physical appearance, drug content, total buoyancy time, or in vitro dissolution pattern after storage at 40°C/75% relative humidity for 3 months.

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Section: Introductionmentioning

confidence: 99%

Development and In Vivo Floating Behavior of Verapamil HCl Intragastric Floating Tablets

et al. 2009

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“…19) The paddle rotation speed was kept at 75 rpm and temperature of 37Ϯ0.5°C was maintained. At predetermined time interval of 1,2,3,4,5,6,7,8,10,12,14,16 and 24 h, 10 ml sample was withdrawn, filtered, suitably diluted and assayed at 288 nm by UV spectrophotometer (Shimadzu 1700).…”

Section: Methodsmentioning

confidence: 99%

“…The controlled gastric retention of solid dosage forms may be achieved by Mucoadhesion, 4) Floatation, 5) Sedimentation, 6) Expansion, 7) Modified shape system 8) and Simultaneous administration of pharmacological agents. 9,10) Gastroretentive floating drug delivery system (GRFDDS) has bulk density lower than gastric fluids and thus remains buoyant in the stomach without affecting the gastric emptying rate for a prolonged period of time.…”

mentioning

confidence: 99%

Preparation and Evaluation of Gastroretentive Floating Tablets of Silymarin

Garg¹,

Gupta²

2009

CHEMICAL & PHARMACEUTICAL BULLETIN

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The present study performed by preparation and evaluation of floating tablets of Silymarin as model drug for prolongation of gastric residence time. Floating effervescent tablets were formulated by various materials like hydroxypropyl methylcellulose (HPMC) K 4M, K 15M, psyllium husk, swelling agent as crospovidone and microcrystalline cellulose and gas generating agent like sodium bicarbonate and citric acid and evaluated for floating properties, swelling characteristics and in vitro drug release studies. Floating noneffervescent tablets were prepared by polypropylene foam powder and different matrix forming polymers like HPMC K 4M, Carbopol 934P, xanthan gum and sodium alginate. In vitro drug release studies were performed and drug release kinetics evaluated using the linear regression method was found to follow both the Higuchi and the Korsemeyer and Peppas equation. The drug release mechanism was found fickian type in most of the formulations. The developed floating tablets of Silymarin may be used in clinic for prolonged drug release for at least 24 h, thereby improving the bioavailability and patient compliance.

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“…In the last few decades various techniques have been developed for gastric retention which is based on the mechanisms of sedimentation [7,8], expansion [9,10] mucoadhesion [11], modified shape systems [12,13], flotation [14], or simultaneous administration of pharmacological agents that delay gastric emptying [15]. These mechanisms are nowadays applied for the preparation of various single and multiple unit dosage forms for large scale manufacture.…”

Section: Introductionmentioning

confidence: 99%

Various Formulation Variables Effecting Floatation Behaviour of Single Unit Gastroretentive Capsules of Ofloxacin

Raza

Khan

2016

Int J Pharm Pharm Sci

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Objective: Objective of the present study was to prepare simple single unit gastro-retentive capsules of ofloxacin with the aim to have the gastric retention of the system for longer periods of time (12h) and to study the effect of various polymers on floating behaviour of such single unit gastroretentive capsules of ofloxacin. Methods:The method used for the preparation of gastro-retentive capsules was a simple physical blending of various low-density hydrophilic polymers alone and in combination with hydrophobic polymers and filling into capsules. These capsules were then subjected to in vitro floatation and matrix integrity study in 0.1N HCl using static volume beaker method and the United States pharmacopoeia (USP) type II dissolution apparatus method at 100rpm.Results: Two grades of hydroxypropyl methylcellulose (HPMC) K4M and K15M used were found suitable for the purpose. Results showed that increase in HPMC level increased colloidal gel barrier strength along with matrix integrity with consequently improved buoyancy. Lactose which was added as release rate modifier decreased matrix integrity and buoyancy. Eudragit a hydrophobic polymer was added so as to have intact, the buoyant formulation for 12 h with desired drug release characteristics. The addition of eudragit enhanced matrix integrity and floatation time to certain levels but higher levels showed negative results. Floatation time of more than 16 h was observed in the formulations containing 2:1 ratio of HPMC K15M and eudragit respectively. 3 2 Conclusion:The study concludes that eudragit S100 a hydrophobic polymer increased floatation time of the formulated capsules with all the three levels of HPMC K15M, but at the same time eudragit level should not exceed HPMC, while lactose a release rate enhancer decreased matrix integrity/floatation time of the formulated capsules.factorial design was used to study the effect of various formulation variables on buoyancy and matrix integrity. Formulations containing zero level of HPMC were found buoyant for more than 12 h with all levels of eudragit S100 (i.e.,-1, 0,+1 level). It was also observed that matrix integrity consequently buoyancy increased with increase in eudragit with all levels of HPMC.

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Evaluation of peroral silicone dosage forms in humans by gamma-scintigraphy

Cited by 76 publications

References 17 publications

Development and In Vivo Floating Behavior of Verapamil HCl Intragastric Floating Tablets

Development and In Vivo Floating Behavior of Verapamil HCl Intragastric Floating Tablets

Preparation and Evaluation of Gastroretentive Floating Tablets of Silymarin

Various Formulation Variables Effecting Floatation Behaviour of Single Unit Gastroretentive Capsules of Ofloxacin

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