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Christmann, Vera; Rosenberg, Jörg; Seega, Jürgen; Lehr, Claus‐Michael

doi:10.1023/a:1012161630481

Cited by 31 publications

(5 citation statements)

References 6 publications

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“…Desired weight of the coated formulation (mg) 25 The loaded capsules were coated with Eudragit L to avoid disintegration in the stomach. The coating solution was prepared by adding Eudragit L into a mixture of isopropanol (97% based on solvent weight) and water while stirring with a magnetic stirrer plate.…”

Section: Capsule Size 9 9hmentioning

confidence: 99%

“…As such, to better understand intestinal transit, non-invasive imaging techniques have been employed to visualise drug delivery systems along the GI tract [20][21][22][23][24]. Techniques such as magnetic resonance imaging (MRI) [25], single-photon emission computed tomography (SPECT) [13] and X-ray imaging [26] have been applied to track the intestinal movement of solid dosage forms following oral administration. For instance, the relationship between the size of the formulations and its gastric emptying in rats has been investigated using microcapsules radiolabelled with 99m Tc-DTPA.…”

Section: Introductionmentioning

confidence: 99%

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Gastrointestinal Tracking and Gastric Emptying of Coated Capsules in Rats with or without Sedation Using CT imaging

Gómez-Lado

Seoane-Viaño

Matiz³

et al. 2020

Pharmaceutics

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Following oral administration, gastric emptying is often a rate-limiting step in the absorption of drugs and is dependent on both physiological and pharmaceutical factors. To guide translation into humans, small animal imaging during pre-clinical studies has been increasingly used to localise the gastrointestinal transit of solid dosage forms. In contrast to humans, however, anaesthesia is usually required for effective imaging in animals which may have unintended effects on intestinal physiology. This study evaluated the effect of anaesthesia and capsule size on the gastric emptying rate of coated capsules in rats. Computed tomography (CT) imaging was used to track and locate the capsules through the gastrointestinal tract. Two commercial gelatine mini-capsules (size 9 and 9h) were filled with barium sulphate (contrast agent) and coated using Eudragit L. Under the effect of anaesthesia, none of the capsules emptied from the stomach. In non-anaesthetised rats, most of the size 9 capsules did not empty from the stomach, whereas the majority of the smaller size 9h capsules successfully emptied from the stomach and moved into the intestine. This study demonstrates that even with capsules designed to empty from the stomach in rats, the gastric emptying of such solid oral dosage forms is not guaranteed. In addition, the use of anaesthesia was found to abolish gastric emptying of both capsule sizes. The work herein further highlights the utility of CT imaging for the effective visualisation and location of solid dosage forms in the intestinal tract of rats without the use of anaesthesia.

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Section: Capsule Size 9 9hmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Gastrointestinal Tracking and Gastric Emptying of Coated Capsules in Rats with or without Sedation Using CT imaging

Gómez-Lado

Seoane-Viaño

Matiz³

et al. 2020

Pharmaceutics

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“…Techniques described on the literature for tracking of solid oral dosage forms in rodents include gamma scintigraphy [31], magnetic resonance imaging (MRI) [32], positron emission tomography (PET) [33], micro-computerized tomography (μCT) [34] and Xray [35]. The latter was simple, cheap and offers simultaneous visualization of both capsule and the GI tract using contrast agents [35].…”

Section: Discussionmentioning

confidence: 99%

Coated minispheres of salmon calcitonin target rat intestinal regions to achieve systemic bioavailability: Comparison between intestinal instillation and oral gavage

Aguirre

Aversa

Rosa

et al. 2016

Journal of Controlled Release

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Achieving oral peptide delivery is an elusive challenge. Emulsion-based minispheres of salmon calcitonin (sCT) were synthesized using single multiple pill (SmPill ® ) technology incorporating the permeation enhancers (PEs): sodium taurodeoxycholate (NaTDC), sodium caprate (C 10 ), or coco-glucoside (CG), or the pH acidifier, citric acid (CA). Minispheres were coated with an outer layer of Eudragit ® L30 D-55 (designed for jejunal release) or Surelease ® /Pectin (designed for colonic release). The process was mild and in vitro biological activity of sCT was retained upon release from minispheres stored up to 4 months. In vitro release profiles suggested that sCT was released from minispheres by diffusion through coatings due to swelling of gelatin and the polymeric matrix upon contact with PBS at pH 6.8.X-ray analysis confirmed that coated minispheres dissolved at the intended intestinal region of rats following oral gavage. Uncoated minispheres at a dose of ~2000 I.U. sCT/kg were administered to rats by intra-jejunal (i.j.) or intra-colonic (i.c.) instillation and caused hypocalcaemia. Notable sCT absolute bioavailability (F) values were: 5.5% from minispheres containing NaTDC (i.j), 17.3% with CG (i.c.) and 18.2 % with C 10 (i.c.). Coated minispheres administered by oral gavage at threefold higher doses also induced hypocalcaemia. A highly competitive F value of 2.7% was obtained for orally-administered sCT-minispheres containing CG (45 μmol/kg) and coated with Eudragit ® . In conclusion, the SmPill ® technology is a potential dosage form for several peptides when formulated with PEs and coated for regional delivery. PK data from instillations over-estimates oral bioavailability and poorly predicts rank ordering of formulations .

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“…NIR has been used to monitor the development of the gel layer formed in compacts containing HPMC (Avalle et al, 2011) as well as monitoring drug release as a result of erosion (Avalle et al, 2013). MRI has been implemented to monitor the movement of water in pastes (Tomer et al, 1999), model polymer dissolution (Kaunisto et al, 2010), visualize in vivo tablet dissolution (Christmann et al, 1997) and to monitor the structural evolution of hypromellose tablets (Kulinowski et al, 2011). A novel imaging application using NMR was also developed and used to monitor water front penetration (Ashraf et al, 1994), water mobility and drug diffusion in hydrophilic matrices (Rajabi-Siahboomi et al, 1996) and drug diffusion in hydrogels (Dinarvand et al, 1995).…”

Section: Introductionmentioning

confidence: 99%

Development of a novel method utilising dissolution imaging for the measurement of swelling behaviour in hydrophilic matrices

Ward

Walton

Mawla

et al. 2019

International Journal of Pharmaceutics: X

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Untitled

Cited by 31 publications

References 6 publications

Gastrointestinal Tracking and Gastric Emptying of Coated Capsules in Rats with or without Sedation Using CT imaging

Gastrointestinal Tracking and Gastric Emptying of Coated Capsules in Rats with or without Sedation Using CT imaging

Coated minispheres of salmon calcitonin target rat intestinal regions to achieve systemic bioavailability: Comparison between intestinal instillation and oral gavage

Development of a novel method utilising dissolution imaging for the measurement of swelling behaviour in hydrophilic matrices

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