uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Drug Solubility in Luminal Fluids from Different Regions of the Small and Large Intestine of Humans
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
Show others and affiliations
2010 (English)In: Molecular pharmaceutics, ISSN 1543-8384, Vol. 7, no 5, 1527-1532 p.Article in journal (Refereed) Published
Abstract [en]

The purpose of this work was to study the solubility of two drugs with different physicochemical properties in luminal fluids obtained from various regions of the human gastrointestinal (GI) tract and to determine the most important luminal parameters influencing their solubility. Jejunal fluids were aspirated from healthy volunteers via an oral intubation tube. Ileal and colonic fluids were obtained from patients undergoing GI surgery. Stoma fluids were also retrieved from patients. pH and buffer capacity of all fluids were determined. Saturation solubility of prednisolone (unionisable) and mesalamine (5-aminosalicylic acid) (zwitterionic) was measured. Mean solubility of prednisolone in the different luminal fluids was 0.50 mg/mL (±0.05) and did not vary significantly between the different regions of the GI tract (ANOVA, p > 0.05). No correlation between prednisolone solubility and jejunal bile salt content was found. Mesalamine solubility increased down the GI tract: 1.97 (±0.25), 3.26 (±0.08), 6.24 (±1.13) and 7.95 (±0.21) mg/mL in jejunal, ileal, ascending and transverse/descending colonic fluids respectively. Buffer capacity also increased and in one patient was observed to range from 6.4 to 28.6 reaching 44.4 mM/L/pH unit in ileal, ascending and transverse/descending colon fluids respectively. Mesalamine solubility was found to be dependent on both buffer capacity and pH, with buffer capacity being the most important (standardized coefficient β = 0.849, p < 0.0001) compared to pH (β = 0.219, p < 0.05). For drugs delivered as modified release formulations it is important to consider solubility in different regions of the GI tract as significant differences can arise which will ultimately influence drug bioavailability.

Place, publisher, year, edition, pages
2010. Vol. 7, no 5, 1527-1532 p.
National Category
Pharmaceutical Sciences
URN: urn:nbn:se:uu:diva-151830DOI: 10.1021/mp100198qPubMedID: 20726533OAI: oai:DiVA.org:uu-151830DiVA: diva2:411415
Available from: 2011-04-18 Created: 2011-04-18 Last updated: 2011-04-21Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed
By organisation
Department of Pharmacy
Pharmaceutical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 134 hits
ReferencesLink to record
Permanent link

Direct link