INVESTIGADORES
QUEVEDO Mario Alfredo
congresos y reuniones científicas
Título:
Complexation of drugs: a new view about the subject
Autor/es:
KOGAWA, A.C.; ZOPPI, A.; QUEVEDO, M.A.; LONGHI, M.R.; NUNES SALGADO, H.R.
Lugar:
Araraquara
Reunión:
Congreso; II International symposium on drug discovery; 2011
Institución organizadora:
Comité Organizador del II International symposium on drug discovery
Resumen:
The cyclodextrins (CDs) are cyclic oligosaccharides
composed of glucose units linked by a -1.4 connections originating from the degradation
of starch by the enzyme glucosyltransferase, synthesized by some
microorganisms. The CDs obtained with higher yields are commonly known natural
and CDs containing six, seven or eight glucose units, are known a-cyclodextrins (CD-a), b-cyclodextrin (b-CD) and cyclodextrin-g (g-CD), respectively. The b-CD is the most widely used in commercial
formulations currently available.
The cyclodextrins are currently classified as
excipients and they have been used in the development of pharmaceuticals,
particularly because of complexing properties, which provide increased
solubility and consequent increase in the rate of dissolution of poorly soluble
drugs, stability, reduction of irritation and reduction or elimination of odors
or flavors in liquid formulations.
Variations in
the physicochemical properties of host-molecules can be identified by analytical
methods, which can detect the formation of complexes. To characterize the
formation of inclusion complexes (IC) in the solid state can be used thermal
methods, infrared spectroscopy, scanning electron microscopy and analysis of
dissolution properties. Already in the liquid state, nuclear magnetic resonance
spectroscopy (NMR) spectroscopy, ultraviolet visible and solubility phase
diagram.
The incorporation
of the CDs in pharmaceutical systems is a consolidated reality. The b-CD is quoted at about $ 5US/kg.
It is expected that the number of formulations containing this adjuvant to expand
considerably in the next years.
Despite the
growing number of studies using CDs in the formation of IC, for photosensitive
drugs is not known what are the advantages of isolating the drug from the
external environment. Therefore, the complexation of doxycycline and b-CD was performed.