Chemical and microbiological evaluation of the internal surfaces of aluminum tubes both unlined and lined with epoxi resin by means of the stereoscope and scanning electron microscope

RESUMO

The internal surfaces of aluminum tubes, both unlined with epoxy resin, which are used for packaged medicines such as creams, ointments, gels, etc., were evaluated chemically, and microbiologically with regard to microorganism adherence. Proof of porosity of the unlined aluminum surface and lined with epoxy resin, and the resistance to removal of the resin were observed using a scanning electron microscope and a stereoscope, with a digitalized image system. to evaluate the microorganisms adherence to the aluminum surface, unlined and lined with epoxy resin, sterilized disks (10mm in diameter) were immersed in Mueller Hinton Broth and placed in tubes of polypropylene with screw caps. The liquid culture medium was then inoculated with suspensions (10(9)CFU/ml) of the following microorganisms Streptococcus agalactiae, Staphylococcus aureus, Acinetobacter Iwoffii and Candida albicans and incubated at 37ºC under constant agitation (100rpm) for 12 days. The culture broth was changed every 3 days, after which the disks were removed, and observed under the scanning electrn microscope. Microscopic observations revealed adherence of the microorganisms and biofilm on the aluminum surfaces both unlined and lined with epoxy resin.