Brain cooling techniques

A simplified pressurised digestion technique was used by Lutyen et al. [30]. Tissue samples (250 mg) were placed in Nalgene bottles, 4 ml of (1 + 1) HN03/HC104 was added and the bottles were sealed and kept at 100°C for 2h. After cooling, the bottles were opened and the solutions diluted with water. This procedure did not work well with brain tissue because of the high lipid content. 

A novel nanoparticulate lipid-based carrier system was developed by Mumper et al. at the University of Kentucky. ° This carrier system is composed of a lipophilic-emulsifying wax such as cetyl alcohol/ polysorbate 60 and other surfactants such as Brij 72, Brij 78, and Tween 80. The nanoparticles were formed through a warm microemulsion technique where encapsulates have included paclitaxel and plasmid DNA. The emulsification process is spontaneous, and cooling of the emulsion causes solidification of the nanoparticle-containing drug. This novel carrier has shown high efficiency in drug delivery across the blood-brain barrier. 

Wolf et al. (2002) investigated extractions of brain cytosol. As only small sample volumes were available, the container material and surface area had severe effects with regard to contamination. These authors found that species extractions should be carried out under cooled conditions and in an inert gas atmosphere, as oxygen from the air immediately oxidizes the species. Rotating pestles or mixers whirl the surrounding gas into the sample. Oxygen from air oxidizes the species immediately. The sonica-tion of biopsy samples proved to be a suitable technique. 

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