Table 4.

5-Fu and Ru rate release kinetics

Model	Parameter	Drug release from hydrogel
		5-Fu at pH 1.2	Ru at pH 1.2	5-Fu at pH 7.4	Ru at pH 7.4
Zero order F = K0 × t	K 0	0.343	0.312	0.405	0.347
	r2 adjusted	0.8703	0.9441	0.834	0.8303
	AIC	58.4938	50.5821	63.8171	61.2646
First order F = 100 × [1 − Exp(−k1 × t)]	K 1	0.006	0.005	0.007	0.006
	r2 adjusted	0.9807	0.9818	0.9695	0.968
	AIC	41.3408	40.4832	48.5719	46.2562
Higuchi model F = KH × t1/2	K 2	4.489	4.034	5.305	4.548
	r2 adjusted	0.9523	0.9147	0.9357	0.9372
	AIC	49.4844	54.3883	55.2872	52.3171
Korsmeyer–Peppas model F = kKP × tn	k KP	2.189	1.096	2.81	2.446
	r2 adjusted	0.9805	0.9818	0.9585	0.9593
	n	0.642	0.758	0.626	0.623
	AIC	43.4613	42.4581	53.3421	50.4105
Hixon–Crowell model F = 100 × [1 − (1 − kHC × t)3]	k HC	0.002	0.001	0.002	0.002
	r2 adjusted	0.965	0.9809	0.9598	0.9462
	AIC	46.7121	40.8944	51.0654	50.9210

AIC akaike information criterion, F fraction of drug release in time t, K₀ apparent rate constant of zero-order release constant, K₁ first-order release constant, K_H Higuchi constant, k_KP Korsmeyer–Peppas rate constant, k_HC Hixon–Crowell constant, n diffusional exponent. And r² = squared correlation coefficient