Permeability and diffusion studies

Permeability and Diffusion Studies Tubules of different composition were filled with sterile glucose (40mg/mL) and insulin (40mg/mL) solutions in phospate buffered saline, pH 7.4 (PBS). The tubules were sealed and then incubated with shaking at 37° C in 5 mL of PBS. Aliquots were removed at different time intervals and the concentration of glucose determined colorimetrically by the glucose oxidase method 21) and insulin by the protein dye binding assay 22). 

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