Table 1 - Formulations of all the samples studied in this work
Sample name
|
Water [mg]
|
Carbomer [mg]
|
Elastamine [mg]
|
2-2
|
10
|
140
|
1200
|
1-2
|
10
|
70
|
1200
|
1-3
|
10
|
70
|
1800
|
1-4
|
10
|
70
|
2400
|
Table 2 - Values of exponent n and drug release regime (diffusion controlled or swelling controlled) for different geometries according to Eq(14).
Solid matrix geometry
|
Diffusion-controlled
|
Swelling-controlled
|
Slab
|
0.50
|
1.00
|
Cylinder
|
0.45
|
0.89
|
Sphere
|
0.43
|
0.85
|
Table 3 – Parameter values for swelling equilibrium estimated from experiments
pH = 3
|
samples
|
Equilibrium swelling
Qv [–]
|
Polymer volume fraction
ϕ [-]
|
Mesh size
ξ [nm]
|
Molecular weight
Mc [g ∙ mol-1]
|
Crosslinking density
ν [μmol ∙ cm-3]
|
2-2
|
7.20
|
0.139
|
13.66
|
11348
|
123.37
|
1-2
|
7.63
|
0.131
|
15.15
|
13416
|
104.35
|
1_3
|
7.92
|
0.126
|
16.15
|
14896
|
93.98
|
1_4
|
7.32
|
0.137
|
14.07
|
11910
|
117.50
|
pH = 7
|
samples
|
Equilibrium swelling
Qv [–]
|
Polymer volume fraction
ϕ [-]
|
Mesh size
ξ [nm]
|
Molecular weight
Mc [g ∙ mol-1]
|
Crosslinking density
ν [μmol ∙ cm-3]
|
2_2
|
13.69
|
0.073
|
42.43
|
70200
|
20.07
|
1_2
|
11.28
|
0.089
|
30.07
|
40750
|
34.36
|
1_3
|
10.29
|
0.098
|
25.63
|
31620
|
45.38
|
1_4
|
8.74
|
0.114
|
19.25
|
19800
|
70.72
|
pH = 10
|
samples
|
Equilibrium swelling
Qv [–]
|
Polymer volume fraction
ϕ [-]
|
Mesh size
ξ [nm]
|
Molecular weight
Mc [g ∙ mol-1]
|
Crosslinking density
ν [μmol ∙ cm-3]
|
2_2
|
8.74
|
0.114
|
19.25
|
19800
|
70.71
|
1_2
|
10.53
|
0.095
|
21.20
|
23155
|
60.46
|
1_3
|
7.96
|
0.126
|
16.31
|
15140
|
92.49
|
1_4
|
6.13
|
0.163
|
10.25
|
7110
|
196.95
|
Table 4 - Parameters in mesh size fitting
pH = 3
|
pH = 7
|
pH = 10
|
α
|
β
|
R2
|
α
|
β
|
R2
|
α
|
β
|
R2
|
-37.87
|
19.20
|
0.999
|
-74.93
|
31.51
|
0.994
|
-44.10
|
21.67
|
0.985
|
Table 5 – Numerical values of the fitting parameters at different pH medium for carbomer samples
pH = 3
|
sample
|
k1 [h-1]
|
k3 [h-1]
|
k5 [h-1]
|
k6 [h-1]
|
a0 [mL]
|
R2
|
tpeak [h]
|
2-2
|
0.71
|
0.10
|
0.50
|
1.25
|
5.81
|
0.953
|
5.00
|
1-2
|
1.03
|
0.23
|
0.52
|
0.81
|
7.45
|
0.985
|
3.20
|
1-3
|
0.45
|
0.15
|
0.50
|
1.51
|
6.00
|
0.904
|
8.00
|
1-4
|
0.27
|
0.20
|
1.50
|
1.91
|
8.00
|
0.850
|
7.00
|
pH = 7
|
sample
|
k1 [h-1]
|
k3 [h-1]
|
k5 [h-1]
|
k6 [h-1]
|
a0 [mL]
|
R2
|
tpeak [h]
|
2-2
|
0.55
|
0.045
|
15.0
|
35.0
|
13.0
|
0.985
|
7.00
|
1-2
|
0.95
|
0.080
|
19.1
|
51.3
|
10.5
|
0.925
|
6.00
|
1-3
|
1.10
|
0.025
|
25.0
|
50.0
|
9.50
|
0.874
|
3.50
|
1-4
|
1.15
|
0.030
|
35.7
|
58.0
|
8.75
|
0.996
|
3.50
|
pH = 10
|
sample
|
k1 [h-1]
|
k3 [h-1]
|
k5 [h-1]
|
k6 [h-1]
|
a0 [mL]
|
R2
|
tpeak [h]
|
2-2
|
0.40
|
0.20
|
1.50
|
1.90
|
8.50
|
0.933
|
5.50
|
1-2
|
0.80
|
0.12
|
0.62
|
1.90
|
8.95
|
0.984
|
4.50
|
1-3
|
0.80
|
0.15
|
0.80
|
1.50
|
7.50
|
0.997
|
4.25
|
1-4
|
0.72
|
0.20
|
1.50
|
2.28
|
8.00
|
0.997
|
4.25
|
Table 6 - Relation between the fitting parameter b and n for RhB release
RhB pH = 3
|
Sample
|
[-]
|
fitted [-]
|
regressed [-]
|
ratio
|
2-2
|
0.720
|
0.539
|
1.124
|
2.06
|
1-2
|
0.694
|
0.571
|
1.087
|
1.90
|
RhB pH = 7
|
2-2
|
0.547
|
0.514
|
0.879
|
1.75
|
1-2
|
0.523
|
0.601
|
0.846
|
1.41
|
1-3
|
0.793
|
0.658
|
1.226
|
1.86
|
RhB pH = 10
|
2-2
|
0.735
|
0.549
|
1.145
|
2.09
|
1-2
|
0.847
|
0.679
|
1.302
|
1.92
|
Table 7 - Relation between the fitting parameter b and n for Esther-RhB release
Ester-bonded RhB pH = 3
|
Sample
|
[-]
|
fitted [-]
|
regressed [-]
|
ratio
|
2-2
|
0.532
|
0.460
|
0.859
|
1.88
|
1-2
|
0.824
|
0.629
|
1.270
|
2.02
|
Ester-bonded RhB pH = 7
|
2-2
|
0.864
|
0.590
|
1.326
|
2.25
|
1-2
|
0.560
|
0.529
|
0.898
|
1.70
|
Ester-bonded RhB pH = 10
|
2-2
|
1.58
|
0.699
|
2.328
|
3.33
|