Table 4 Diffusion release kinetics of immediate and sustained release tablet layers

Formulation

Best fit model

Equation

r ²

n

Equation

r ²

Mechanism

F1

First order

y = − 0.0226x + 1.6196

0.9078

0.334

y = 0.2739x − 0.4522

0.7702

Fickian

F2

First order

y = − 0.0064x + 1.8573

0.8981

0.383

y = 0.4323x − 0.8939

0.8817

Fickian

F3

Hixson-Crowell

y = 0.06x + 3.6677

0.9864

0.389

y = 0.4805x − 0.9347

0.8964

Fickian

F4

Korsmeyer-Peppas

y = 0.366x − 0.6456

0.8535

0.371

y = 0.366x − 0.6456

0.8535

Fickian

F5

First order

y = − 0.0137x + 1.739

0.8803

0.359

y = 0.3658x − 0.6449

0.8266

Fickian

F6

Hixson-Crowell

y = 0.0858x + 3.7455

0.9653

0.376

y = 0.3157x − 0.5529

0.8656

Fickian

F7

First order

y = − 0.0186x + 1.5783

0.8216

0.328

y = 0.2827x − 0.4703

0.7561

Fickian

F8

First order

y = − 0.0085x + 1.8671

0.9391

0.389

y = 0.4753x − 0.9229

0.8967

Fickian

F9

First order

y = − 0.0142x + 1.7476

0.8879

0.364

y = 0.3737x − 0.6561

0.8377

Fickian

F10

First order

y = − 0.01x + 1.8595

0.9538

0.390

y = 0.4587x − 0.87

0.8977

Fickian

F11

First order

y = − 0.0157x + 1.6437

0.7914

0.343

y = 0.3278x − 0.5575

0.7895

Fickian

F12

First order

y = − 0.0173x + 1.6354

0.8107

0.344

y = 0.3177x − 0.5354

0.7922

Fickian

F13

First order

y = − 0.0135x + 1.734

0.8435

0.354

y = 0.3859x + 0.6751

0.8152

Fickian

Formulation

Best fit model

Equation

r ²

n

Equation

r ²

Mechanism

M1

Zero order

y = 0.0022x − 0.0631

0.9827

0.423

y = 1.6637x − 4.4097

0.9752

Fickian

M2

Zero order

y = 0.002x − 0.0624

0.9834

0.428

y = 1.9599x − 5.1506

0.9864

Fickian

M3

Zero order

y = 0.002x − 0.0616

0.9823

0.420

y = 2.0632x − 5.4212

0.9673

Fickian

M4

Zero order

y = 0.002x − 0.0606

0.9808

0.416

y = 2.1563x − 5.6404

0.9585

Fickian

M5

Zero order

y = 0.0022x − 0.0453

0.9943

0.429

y = 1.5957x − 4.177

0.9881

Fickian

M6

Hixson-Crowell

y = 0.0023x + 3.6243

0.9926

0.419

y = 1.075x − 2.5834

0.9642

Fickian

M7

Hixson-Crowell

y = 0.0022x + 3.6278

0.9918

0.418

y = 1.0974x − 2.6311

0.9629

Fickian

M8

Zero order

y = 0.0021x − 0.0395

0.9862

0.421

y = 2.0706x − 5.349

0.9703

Fickian

M9

Zero order

y = 0.0023x − 0.0505

0.9891

0.420

y = 1.8033x − 4.6924

0.9683

Fickian

M10

Zero order

y = 0.0023x − 0.0375

0.9861

0.419

y = 1.7073x − 4.4308

0.9659

Fickian

M11

Hixson-Crowell

y = 0.0023x + 3.6319

0.9936

0.427

y = 0.8891x − 2.1579

0.9844

Fickian

M12

Zero order

y = 0.0022x − 0.0495

0.9908

0.427

y = 1.7463x − 4.5495

0.9832

Fickian

M13

Hixson-Crowell

y = 0.0023x + 3.6209

0.9971

0.420

y = 1.0704x − 2.5704

0.9674

Fickian