Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1573-904X
    Keywords: moxalactam ; epimerization ; frozen solution ; ice ; activation energy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The epimerization rate constants of R- and S-epimers of moxalactam (LMOX) in a frozen aqueous solution decreased as the temperature decreased. The reaction proceeded in the unfrozen region remaining in the frozen solution, without being affected by the ice. The reaction stopped completely below the collapse temperature of the LMOX aqueous solution. The ratio of R- and S-epimers at equilibrium, which was equal to the ratio of the epimerization rate constant, increased as the temperature decreased. This change in the ratio at equilibrium could be ascribed to the difference in the activation energy between the two epimers.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-904X
    Keywords: nonhardened gelatin–acacia microcapsules ; complex coacervation ; bioavailability ; lipophilic drugs ; O/W emulsions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Nonhardened gelatin-acacia microcapsules were studied for encapsulation of microdroplets of oil solution containing a lipophilic drug as core material and ready disintegration with release of micro oil droplets in the gastrointestinal tract. Probucol and S-312-d, a Ca-channel blocker, were employed as model lipophilic drugs. Glyceryl tricaprylate and tricaprate mixture solutions containing these drugs were encapsulated according to the complex coacervation method and were recovered as free-flowing powders without any hardening (cross-linking) step. The microcapsules obtained were disintegrated, and the emulsion was reproduced within 3 min at 37°C in the first or second test solution defined in the Japanese Pharmacopeia XII. When the microcapsules were stored as a powder at room temperature in a closed bottle, no significant change in their appearance or disintegration time upon rehydration was observed even after 1 year. Oral bioavailabilities of model drugs from the microcapsules were tested in rats and dogs and compared with those from other conventional formulations. Gastrointestinal absorption of both probucol and S-312-d from the microcapsules was remarkably more efficient than that from other formulations such as powders, granules, or oil solution. The proposed method for microencapsulation could be useful for powdering drug-containing oil solutions or O/W emulsions while maintaining excellent bioavailability.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...