Fig. 4.

a Uptake of [³H] biotin by HCEC and D407 cells as a function of temperature (37°C, 25°C and 4°C). [³H] biotin uptake was performed at different temperatures with DPBS buffer (pH 7.4) for 30 min. Values represent mean ± SD (n = 4). A P value of < 0.05 is considered to be statistically significant and denoted by *. b Arrhenius plot of the effect of temperature on [³H] biotin uptake by HCEC and D407 cells