. 2015 Mar 20;24(1):82–91. doi: 10.1016/j.jsps.2015.03.005

Table 7.

Release kinetics of metformin hydrochloride matrix tablets in phosphate buffer pH 6.8 at 37 °C.

Formulation	Zero order R²	First order R²	Higuchi R²	Hixson-Crowell R²	Korsmeyer-Peppas R²
M1	0.6775	0.6839	0.8008	0.6807	0.4395
M2	0.6682	0.6642	0.8019	0.6712	0.5701
M3	0.6726	0.6795	0.7937	0.6703	0.4326
M4	ND	ND	ND	ND	ND
M5	0.7511	0.8664	0.9013	0.8440	0.8346
M6	0.8783	0.9579	0.9410	0.9863	0.9396
M7	0.8793	0.9532	0.9452	0.9308	0.9477
M8	0.8959	0.9558	0.9640	0.9899	0.8981
M9	0.9035	0.9528	0.9618	0.9332	0.8865
M10	0.8129	0.9354	0.9029	0.9491	0.9099
M11	0.9119	0.9667	0.9671	0.9759	0.9682
M12	0.9580	0.9942	0.9893	0.9939	0.9754
M13	0.9713	0.9822	0.9753	0.9871	0.9557
ST-M	0.9434	0.9937	0.9785	0.9852	0.8532

ND = Not determined due to insufficient data points; ST-M = Glucophage® (standard metformin tablet).