Study of the sodium phenytoin effect on the formation of sol–gel SiO2 nanotubes by TEM

Microencapsulation is a versatile technology that allows controlling the release of different active molecules. Recently the sol–gel process has emerged like a promising method to immobilization and stabilization of biologically active compounds like enzymes, antigens,microorganisms and drugs. Porous silica and titanium dioxide materials made by low temperature sol–gel processes are promising host matrixes for encapsulation of biological molecules. The preparation of a low-temperature silica sol followed by gelation to neutral pH with water for injection containing the antiepileptic drug is reported here. The structure is very important so the analysis of the new developed material is also reported. Particularly interesting is the presence of nanotubes and microtubes,produced in the inorganic matrix in the presence of the sodium phenytoin. The use of transmission electron microscopy and quantum mechanics molecular simulation allows determining a micelle-like effect during the synthesis of these materials,which controls the size,structure and stability of them. 2004 Elsevier B.V. All rights reserved.