Sustained Release and Cytotoxicity Evaluation of Carbon Nanotube-Mediated Drug Delivery System for Betulinic Acid

Table 1

Correlation coefficient, rate constant, and half-life obtained by fitting the data for release of BA from f-SWCNTs-BA into PBS solutions at pH 7.4 and 4.8.

Aqueous solution	Saturated release (%)				Rate constant, (mg/min)	(min)
		Pseudo-first order	Pseudo-second order	Parabolic diffusion
pH 7.4	89.2	0.8817	0.9992	0.7054		32
pH 4.8	78.7	0.2236	0.9996	0.6421		15

Note: estimated using pseudo-second order kinetics.