Nano-appended transdermal gel of Tenoxicam via ultradeformable drug carrier system

Figures & data

Table 1. Composition of gels.

Ingredients	Formulations (% w/w)
	G-1	G-2	G-3	G-4^a
Tenoxicam (in vesicles)	0.1	0.1	0.1	0.1
Carbopol	1	1.5	2	1.5
Triethanolamine	0.5	0.5	0.5	0.5
Methyl paraben	0.1	0.1	0.1	0.1
Propyl paraben	0.1	0.1	0.1	0.1
Phosphate buffer (pH 7.4)	q.s.	q.s.	q.s.	q.s.
Notes: q.s., quantity sufficient ^aG-4 contains free drug.

Figure 1. DSC thermograms of Tenoxicam and final gel formulation.

Figure 2. Transmission electron microscope photographs of (T3) Tenoxicam-loaded ultradeformable vesicles (magnification × 100,000).

Figure 3. Effect of concentrations of different surfactants on the size of ultradeformable vesicles. Notes: S.D.C. is sodium desoxycholate. *Significant (p < 0.05) compared to T3.

Figure 4. Effect of concentrations of different surfactants on the deformability of ultradeformable vesicles. Note: *Significant (p < 0.05) compared to T3.

Table 2. Comparative kinetic analysis of vesicles: release rate constants (k), correlation coefficients (R ²), and release exponent (n) of different ultradeformable vesicles.

Formulation code	Zero order		First order		Higuchi		Korsmeyer–Peppas
	k	R ^2	k	R ^2	k	R ^2	Release exponent (n)	R ^2
T1	1.075	0.767	−0.010	0.840	5.513	0.960	0.275	0.994
T2	2.526	0.919	−0.020	0.970	12.970	0.992	0.745	0.998
T3	8.181	0.936	−0.066	0.948	21.320	0.987	0.642	0.994
S1	2.664	0.954	−0.019	0.977	13.220	0.969	0.726	0.988
S2	3.715	0.957	−0.037	0.983	18.810	0.991	0.720	0.990
S3	3.018	0.986	−0.024	0.950	14.640	0.928	0.621	0.977
C1	2.002	0.887	−0.011	0.887	9.856	0.843	0.367	0.992
C2	1.323	0.913	−0.007	0.969	6.413	0.967	0.245	0.997
C3	1.144	0.770	−0.010	0.820	6.029	0.945	0.346	0.990

Table 3. Comparative features of different ultradeformable vesicles (n = 3).

Formulation code	Total percentage release ± SEM (24 h)	Percentage entrapment ± SEM	Size (nm) ± SEM	Zeta potential (mV) ± SEM	Deformability index ± SEM
T1	28.58 ± 1.08	37.90 ± 0.34	92.34 ± 1.98	−16.53 ± 1.14	6.63 ± 0.25
T2	60.51 ± 0.71	64.67 ± 0.46	100.23 ± 0.17	−16.77 ± 0.23	17.04 ± 0.30
T3	98.01 ± 0.33	62.10 ± 0.68	82.80 ± 074	−13.83 ± 0.72	31.27 ± 0.28
S1	68.16 ± 2.57	59.54 ± 2.47	104.63 ± 0.50	−18.30 ± 0.90	19.97 ± 0.34
S2	88.40 ± 0.50	53.70 ± 2.27	93.00 ± 0.50	−28.63 ± 1.23	27.80 ± 0.25
S3	76.76 ± 0.68	57.56 ± 3.93	122.26 ± 1.24	−20.63 ± 0.89	25.85 ± 0.72
C1	43.58 ± 0.23	62.38 ± 0.02	115.50 ± 1.33	−22.57 ± 0.72	12.49 ± 0.41
C2	37.17 ± 1.01	51.66 ± 2.27	154.63 ± 2.50	−21.67 ± 0.27	9.82 ± 0.81
C3	28.81 ± 0.97	45.70 ± 0.82	117.66 ± 2.23	−22.60 ± 0.90	4.48 ± 0.09

Figure 5. Comparative release profile of optimised ultradeformable vesicle suspension and free drug solution.

Figure 6. Frequency sweep curves of different gel formulations.

Table 4. Comparative kinetic analysis of gels: release rate constants (k), correlation coefficients (R ²), and release exponent (n) of gels of different concentrations.

Formulation code	Zero order		First order		Higuchi		Korsmeyer–Peppas
	k	R ^2	k	R ^2	k	R ^2	Release exponent (n)	R ^2
G-1	2.191	0.99	−0.013	0.998	10.45	0.956	0.532	0.997
G-2	2.266	0.972	−0.014	0.991	11.02	0.976	0.457	0.996
G-3	1.828	0.961	−0.01	0.982	8.957	0.978	0.454	0.996

Figure 7. Comparative release profile (dialysis membrane) of optimised gel formulation and free drug gel (n = 3).

Figure 8. Comparative release profile (rat skin) of optimised gel formulation and free drug gel (n = 3).

Figure 9. Comparative pharmacodynamic analysis of Tenoxicam ultradeformable vesicle G-2, Tenoxicam oral suspension in distilled water and marketed aceclofenac gel (Hifenac®) formulation by the carrageenan-induced rat paw oedema model.

Table 5. Effect of different storage conditions on total percentage release (n = 3).

Time (months)	Percentage cumulative release (24 h) ± SEM
	5 ± 3°C	25 ± 2°C
0	57.50 ± 1.41	57.66 ± 1.30
1	56.75 ± 0.23	56.08 ± 0.349
2	56.60 ± 0.09	53.50 ± 0.24
3	55.51 ± 0.20	52.43 ± 0.255