Effect of polycarbophil concentration on in vitro release and in vivo availability in beagle dogs of dihydroergotamine mesylate suppositories

Abstract Aim The in vivo pharmacokinetics of thermoplastic-coated tablets prepared by a new technology of thermoplastic coating in Beagle dogs were studied, and the correlation between in vitro release and in vivo absorption was analyzed. Methods The in vitro release profiles of metformin hydrochloride thermoplastic-coated tablets and nifedipine thermoplastic-coated tablets were investigated. The single-dose pharmacokinetic study of these tablets in Beagle dogs was performed, and the obtained results were separately compared with the data of conventional osmotic pump tablets reported in the literature. Results Metformin hydrochloride thermoplastic-coated tablets and nifedipine thermoplastic-coated tablets displayed controlled drug-release characteristics and had a good in vivo–in vitro correlation in Beagle dogs, respectively. The literature-compared results further demonstrated that both thermoplastic-coated tablets had release characteristics of osmotic pump tablets in vivo. Conclusion The thermoplastic-coated tablets could control drug release in vivo and it was further confirmed that the new thermoplastic coating technology could replace the spray coating of osmotic pump controlled-release tablets. This study provides a theoretical basis and practical support for the industrialization and clinical application of the new thermoplastic coating technology.

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Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651094 ◽

1987 ◽

Vol 57 (02) ◽

pp. 201-204 ◽

Cited By ~ 2

Author(s):

P Y Scarabin ◽

L Strain ◽

C A Ludlam ◽

J Jones ◽

E M Kohner

Keyword(s):

In Vitro Release ◽

Mean Value ◽

Reliable Estimate ◽

Diabetic Patients ◽

Single Measurement ◽

Diabetic Population ◽

The Difference ◽

Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

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Development, in vitro and in vivo Evaluations of Solid-Lipid Microparticles based on Solidified Micellar Carrier System for Oral Delivery of Cefepime

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2017.10.1.3 ◽

2017 ◽

Vol 10 (1) ◽

pp. 3582-3593

Author(s):

Chukwuebuka Umeyor ◽

Uchechukwu Nnadozie ◽

Anthony Attama

Keyword(s):

Oral Delivery ◽

In Vitro Release ◽

Carrier System ◽

Solid Lipid ◽

Solid Lipid Microparticles ◽

Release Study ◽

Lipid Microparticles ◽

Vitro Release

This study seeks to formulate and evaluate a solid lipid nanoparticle-based, solidified micellar carrier system for oral delivery of cefepime. Cefepime has enjoyed a lot of therapeutic usage in the treatment of susceptible bacterial infections; however, its use is limited due to its administration as an injection only with poor patient compliance. Since oral drug administration encourage high patient compliance with resultant effect in improved therapy, cefepime was formulated as solid lipid microparticles for oral delivery using the concept of solidified micellar carrier system. The carrier system was evaluated based on particle yield, particle size and morphology, encapsulation efficiency (EE %), and thermal analysis using differential scanning calorimeter (DSC). Preliminary microbiological studies were done using gram positive and negative bacteria. In vitro release study was performed using biorelevant media, while in vivo release study was performed in white albino rats. The yield of solid lipid microparticles (SLM) ranged from 84.2 – 98.0 %. The SLM were spherical with size ranges of 3.8 ± 1.2 to 42.0 ± 1.4 µm. The EE % calculated ranged from 83.6 – 94.8 %. Thermal analysis showed that SLM was less crystalline with high potential for drug entrapment. Microbial studies showed that cefepime retained its broad spectrum anti-bacterial activity. In vitro release showed sustained release of cefepime from SLM, and in vivo release study showed high concentration of cefepime released in the plasma of study rats. The study showed that smart engineering of solidified micellar carrier system could be used to improve oral delivery of cefepime.

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Formulation and Evaluation of Itopride Hydrochloride Floating Beads for Gastroretentive Delivery

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2013.6.4.10 ◽

2013 ◽

Vol 6 (4) ◽

pp. 2269-2280

Author(s):

Nagratna Dhople ◽

P N Dandag ◽

A P Gadad ◽

C K Pandey ◽

Masthiholimath V S

Keyword(s):

Sustained Release ◽

In Vitro Release ◽

Entrapment Efficiency ◽

Sustained Release Formulation ◽

Prokinetic Drug ◽

Drug Entrapment Efficiency ◽

Itopride Hydrochloride ◽

Vitro Release

A gastroretentive sustained release system of itopride hydrochloride was formulated to increase the gastric residence time and modulate its release behavior. Itopride hydrochloride is a prokinetic drug used in the treatment of gastroeosophageal reflux disease, Non-ulcer dyspepsia and as an antiemetic. Hence, itopride hydrochloride beads were prepared by emulsion gelation method by employing low methoxy pectin and sodium alginate as sustained release polymers in three different ratios alone and in combination and sunflower oil was used to enable floating property to the beads. The effect of variation in polymer and their concentration was investigated. The beads were evaluated for production yield, particle size, swelling index, density measurement, buoyancy, drug content, drug entrapment efficiency, in vitro release characteristics and release kinetic study. Based on drug entrapment efficiency, buoyancy, swelling and in vitro release, F9 was selected as the optimized formulation. F9 was further subjected to surface morphology by SEM, in vitro release comparison with marketed formulation, in vivo floating study in rabbits and stability study for 90 days. In vitro release follows zero order and fitted in Korsmeyer peppas model (Non-Fickian release). Therefore, the rate of drug release is due to the combined effect of drug diffusion and polymer swelling. The in vivo X-ray studies revealed that the beads were floating in the rabbit stomach up to 10 hours. Thus, it was concluded that the sustained release formulation containing itopride hydrochloride was found to improve patient compliance, minimize the side effects and decrease the frequency of administration.

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