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Chitosan-genipin microspheres for the controlled release of drugs: clarithromycin, tramadol and heparin.

Harris R, Lecumberri E, Heras A - Mar Drugs (2010)

Bottom Line: Once the crosslinking process was characterized as a function of the factors mentioned above, drug loaded hydrochloride chitosan microspheres with different degrees of crosslinking were obtained.In conclusion, genipin showed to be eligible as a chemical-crosslinking agent delaying the outflow of drugs from the microspheres.However, more studies in vitro and in vivo must be carried out to determine adequate crosslinking conditions for different drugs.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Estudios Biofuncionales, Departamento Química-Física II, Universidad Complutense Paseo Juan XXIII, Madrid, Spain. ruthharris@ieb.ucm.es

ABSTRACT
The aim of this study was to first evaluate whether the chitosan hydrochloride-genipin crosslinking reaction is influenced by factors such as time, and polymer/genipin concentration, and second, to develop crosslinked drug loaded microspheres to improve the control over drug release. Once the crosslinking process was characterized as a function of the factors mentioned above, drug loaded hydrochloride chitosan microspheres with different degrees of crosslinking were obtained. Microspheres were characterized in terms of size, morphology, drug content, surface charge and capacity to control in vitro drug release. Clarithromycin, tramadol hydrochloride, and low molecular weight heparin (LMWH) were used as model drugs. The obtained particles were spherical, positively charged, with a diameter of 1-10 microm. X-Ray diffraction showed that there was an interaction of genipin and each drug with chitosan in the microspheres. In relation to the release profiles, a higher degree of crosslinking led to more control of drug release in the case of clarithromycin and tramadol. For these drugs, optimal release profiles were obtained for microspheres crosslinked with 1 mM genipin at 50 °C for 5 h and with 5 mM genipin at 50 °C for 5 h, respectively. In LMWH microspheres, the best release profile corresponded to 0.5 mM genipin, 50 °C, 5 h. In conclusion, genipin showed to be eligible as a chemical-crosslinking agent delaying the outflow of drugs from the microspheres. However, more studies in vitro and in vivo must be carried out to determine adequate crosslinking conditions for different drugs.

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The chemical structure of genipin.
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f1-marinedrugs-08-01750: The chemical structure of genipin.

Mentions: Geniposide is extracted from the fruit of Gardenia jasminoides Ellis, traditionally used in oriental medicine for the treatment of inflammation, headache, and hepatic disorders among others [3]. Its aglycone, genipin (Figure 1), has recently attracted much interest as a crosslinking agent for biomedical use because of its biocompatibility and because it forms stable and biocompatible crosslinked products [4,5]. The formation of crosslinks between genipin and primary amine groups [5] and the finding that genipin-crosslinked networks are significantly less cytotoxic than those crosslinked by glutaraldehyde [6] prompted us to use this chemical as a crosslinking agent to develop chitosan microspheres for controlled drug release.


Chitosan-genipin microspheres for the controlled release of drugs: clarithromycin, tramadol and heparin.

Harris R, Lecumberri E, Heras A - Mar Drugs (2010)

The chemical structure of genipin.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2901822&req=5

f1-marinedrugs-08-01750: The chemical structure of genipin.
Mentions: Geniposide is extracted from the fruit of Gardenia jasminoides Ellis, traditionally used in oriental medicine for the treatment of inflammation, headache, and hepatic disorders among others [3]. Its aglycone, genipin (Figure 1), has recently attracted much interest as a crosslinking agent for biomedical use because of its biocompatibility and because it forms stable and biocompatible crosslinked products [4,5]. The formation of crosslinks between genipin and primary amine groups [5] and the finding that genipin-crosslinked networks are significantly less cytotoxic than those crosslinked by glutaraldehyde [6] prompted us to use this chemical as a crosslinking agent to develop chitosan microspheres for controlled drug release.

Bottom Line: Once the crosslinking process was characterized as a function of the factors mentioned above, drug loaded hydrochloride chitosan microspheres with different degrees of crosslinking were obtained.In conclusion, genipin showed to be eligible as a chemical-crosslinking agent delaying the outflow of drugs from the microspheres.However, more studies in vitro and in vivo must be carried out to determine adequate crosslinking conditions for different drugs.

View Article: PubMed Central - PubMed

Affiliation: Instituto de Estudios Biofuncionales, Departamento Química-Física II, Universidad Complutense Paseo Juan XXIII, Madrid, Spain. ruthharris@ieb.ucm.es

ABSTRACT
The aim of this study was to first evaluate whether the chitosan hydrochloride-genipin crosslinking reaction is influenced by factors such as time, and polymer/genipin concentration, and second, to develop crosslinked drug loaded microspheres to improve the control over drug release. Once the crosslinking process was characterized as a function of the factors mentioned above, drug loaded hydrochloride chitosan microspheres with different degrees of crosslinking were obtained. Microspheres were characterized in terms of size, morphology, drug content, surface charge and capacity to control in vitro drug release. Clarithromycin, tramadol hydrochloride, and low molecular weight heparin (LMWH) were used as model drugs. The obtained particles were spherical, positively charged, with a diameter of 1-10 microm. X-Ray diffraction showed that there was an interaction of genipin and each drug with chitosan in the microspheres. In relation to the release profiles, a higher degree of crosslinking led to more control of drug release in the case of clarithromycin and tramadol. For these drugs, optimal release profiles were obtained for microspheres crosslinked with 1 mM genipin at 50 °C for 5 h and with 5 mM genipin at 50 °C for 5 h, respectively. In LMWH microspheres, the best release profile corresponded to 0.5 mM genipin, 50 °C, 5 h. In conclusion, genipin showed to be eligible as a chemical-crosslinking agent delaying the outflow of drugs from the microspheres. However, more studies in vitro and in vivo must be carried out to determine adequate crosslinking conditions for different drugs.

Show MeSH