Critical Dissolution Tests of Oral Systems Based on Statistically Designed Experiments. IH. In Vitro/In Vivo Correlation for Multiple-Unit Capsules of Paracetamol Based on PLS Modeling

Despite the presumption of the beneficial effects of magnesium supplementation, little is known about the pharmacokinetics of different magnesium formulations. We aimed to investigate the value of two in vitro approaches to predict bioavailability of magnesium and to validate this in subsequent in vivo testing. In vitro assessment of 15 commercially available magnesium formulations was performed by means of a Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) and by dissolution tests. Two magnesium formulations with contrasting bioavailability prediction from both in vitro tests (best vs. worst) were selected for in vivo testing in 30 subjects. In vivo bioavailability was compared following one acute ingestion by monitoring blood magnesium concentrations up to 6 h following intake. The in vitro tests showed a very wide variation in absorption and dissolution of the 15 magnesium products. In the in vivo testing, a significant different serum magnesium absorption profile was found up to 4 h following supplement ingestion for the two supplements with opposing in vitro test results. Moreover, maximal serum magnesium increase and total area under the curve were significantly different for both supplements (+6.2% vs. +4.6% and 6.87 vs. 0.31 mM.min, respectively). Collectively, poor bioaccessibility and bioavailability in the SHIME model clearly translated into poor dissolution and poor bioavailability in vivo. This provides a valid methodology for the prediction of in vivo bioavailability and effectiveness of micronutrients by specific in vitro approaches.

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Development of Multiple-Unit Floating Drug Delivery System of Clarithromycin: Formulation, in vitro Dissolution by Modified Dissolution Apparatus, in vivo Radiographic Studies in Human Volunteers

Drug Research ◽

10.1055/s-0043-102952 ◽

2017 ◽

Vol 67 (07) ◽

pp. 412-418 ◽

Cited By ~ 2

Author(s):

Arun Reddy ◽

Narendar Reddy

Keyword(s):

Drug Release ◽

Residence Time ◽

Release Kinetics ◽

In Vitro Dissolution ◽

Physical Parameters ◽

Gastric Residence Time ◽

Human Volunteers ◽

Multiple Unit

AbstractClarithromycin (CM), a broad spectrum macrolide antibiotic used to eradicate H. pylori in peptic ulcer. Clarithromycin (CM) is well absorbed from the gastrointestinal tract, but has a bioavailability of 50% due to rapid biodegradation. The aim of this investigation was to increase the gastric residence time, and to control the drug release of clarithromycin by formulating into multiple unit floating mini-tablets. Floating tablets were prepared by using direct compression method with HPMC K4M and Polyox WSR 1105 as release retarded polymers and sodium bicarbonate as gas generating agent. The prepared mini-tablets were evaluated for thickness, weight variation, friability, hardness, drug content, in vitro buoyancy, swelling studies, in vitro dissolution studies by using modified Rossett-Rice test and in vivo radiographic studies in healthy human volunteers in fasting conditions. DSC analysis revealed that no interaction between drug and excipients. All the physical parameters of the tablets were within the acceptable limits. The optimized formulation (F6) had showed controlled drug release of 99.16±3.22% in 12 h, by zero-order release kinetics, along with floating lag time of 9.5±1.28 s and total floating time of 12±0.14 h. X-ray imaging studies revealed that in vivo gastric residence time of clarithromycin floating mini-tablet in the stomach was about 3.5 h. The results demonstrated that the developed floating mini-tablets of clarithromycin caused significant enhancement in gastric retention time along with sustained effect and increased oral bioavailability.

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Formulation and In Vitro Evaluation of Pellets Containing Sulfasalazine and Caffeine to Verify Ileo-Colonic Drug Delivery

Pharmaceutics ◽

10.3390/pharmaceutics13121985 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1985

Author(s):

Annemarie Broesder ◽

Said Y. Bircan ◽

Anneko B. de Waard ◽

Anko C. Eissens ◽

Henderik W. Frijlink ◽

...

Keyword(s):

Drug Delivery ◽

Pure Water ◽

Granulation Process ◽

Target Drug ◽

Colonic Drug Delivery ◽

Dissolution Tests ◽

Ph Dependent ◽

Release Profiles

The ColoPulse coating is a pH-dependent coating that can be used to target drug release to the ileo-colonic region. ColoPulse coated tablets and capsules have demonstrated their targeting capabilities in vivo in more than 100 volunteers and patients. However, so far the ColoPulse coating has not been used for multi-particulate pellet formulations. The sulfasalazine–caffeine method can be used to confirm ileo-colonic drug delivery in vivo. Caffeine serves as a release marker in this method, while sulfasalazine serves as a marker for colonic arrival. In this study, extrusion–spheronization was used to produce microcrystalline cellulose based pellets containing both caffeine and sulfasalazine. Dissolution tests revealed that a superdisintegrant, i.e., croscarmellose sodium or sodium starch glycolate, should be incorporated in the formulation to achieve acceptable release profiles for both sulfasalazine and caffeine. However, acceptable release profiles were only obtained when the pelletizing liquid consisted of ethanol/water 1/1 (v/v) but not with pure water. This phenomenon was ascribed to the differences in the degree of swelling of the superdisintegrant in the pelletizing liquid during the granulation process. The pellets were coated with the ColoPulse coating and showed the desired pH-dependent pulsatile release profile in vitro. In future clinical studies, ileo-colonic targeting should be verified.

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