Characterization and evaluation of a self-microemulsifying drug delivery system containing tectorigenin, an isoflavone with low aqueous solubility and poor permeability

Figures & data

Table 1. Stability evaluation of TG-SMEDDS after been long-term saved (x±s, n = 3).

Time (month)	Appearance	Content (%)	Particle size (nm)	PDI	Viscosity (mpa × s)
0	Yellow clear liquid	98.70 ± 0.31	14.80 ± 0.64	0.116 ± 0.009	2.15 ± 0.03
1	Yellow clear liquid	98.64 ± 0.67	14.91 ± 0.13	0.115 ± 0.004	2.14 ± 0.01
2	Yellow clear liquid	97.30 ± 0.25	15.07 ± 0.77	0.113 ± 0.010	2.17 ± 0.06
3	Yellow clear liquid	97.81 ± 0.20	14.98 ± 0.67	0.116 ± 0.014	2.18 ± 0.03

Figure 1. Dissolution profiles of crude TG in pH 1.2 (a, black square) or in pH 6.8 buffer solution (a, blank square), and TG-SMEDDS in pH 1.2 (b, black triangle) or in pH 6.8 buffer solution (b, blank triangle).

Table 2. Absorption percentage per hour of TG in gastric perfusate (%, n = 5).

Parameter	TG-SMEDDS	TG
P %	31.43 ± 0.30	29.65 ± 5.43
AMU	13.39 ± 1.59	13.46 ± 1.34
P′%	18.04	16.19

AMU, percentage of attachment, metabolism, uptaking by stomach per hour.

P′%, corrected absorption percentage per hour, P′% = P%-AMU.

Table 3. Absorption parameters of TG at intestinal segments (x±s, n = 5).

	Duodenum		Jejunum		Ileum		Colon
Perfusate	Ps /%	P /%·cm^−2	Ps /%	P/ %·cm^−2	Ps /%	P/ %·cm^−2	Ps /%	P/ %·cm^−2
TG	1.65 ± 0.30	0.55 ± 0.08	1.23 ± 0.29	0.41 ± 0.08	3.21 ± 0.41*	1.07 ± 0.18*	2.16 ± 0.18	0.72 ± 0.07
TG-SMEDDS	4.02 ± 0.37♦	1.34 ± 0.12♦	3.07 ± 0.30	1.10 ± 0.17	3.38 ± 0.40	1.13 ± 0.12	2.31 ± 0.08	0.77 ± 0.03

*p < 0.05, compared the two parameters of TG in ileum with those in other intestinal segments.

♦ p < 0.05, compared the two parameters of TG-SMEDDS in duodenum with those in other intestinal segments.

Figure 2. Mean plasma concentration–time profile of TG-SMEDDS/TG after orally administered to rats (a); mean plasma concentration-time profile of TG-SMEDDS after orally administered to non-ligation or ligation rats (b); mean plasma concentration–time profile of TG after orally administered to non-ligation or ligation rats (c).

Table 4. Statistical moment parameters of TG in rats after oral administration of TG/TG-SMEDDS in rats.

Parameters	TG	TG-SMEDDS	TG^a	TG-SMEDDS^a
AUC0-t (mg/L × h)	2.700 ± 1.012	13.588 ± 3.756♦	0.446 ± 0.174	4.851 ± 0.674
AUC0-∞ (mg/L × h)	3.004 ± 0.985	15.437 ± 5.981♦	0.553 ± 0.312	5.422 ± 0.617
MRT (h)	6.98 ± 0.69	20.11 ± 2.36	3.31 ± 0.73	17.13 ± 3.99
t1/2z (h)	4.98 ± 1.52	18.68 ± 7.43	2.60 ± 1.64	13.84 ± 2.38
Tmax (h)	1.00 ± 0.61	0.12 ± 0.05	0.70 ± 0.28	0.60 ± 0.22
	5.20 ± 1.79^b	4.00 ± 2.45^b
CLz/F (L/h/kg)	14.34 ± 3.99	2.83 ± 0.79	91.30 ± 45.86	7.46 ± 0.93
Vz/F (L/kg)	99.90 ± 37.59	70.43 ± 17.20	284.06 ± 97.78	210.64 ± 131.56
Cmax (mg/L)	0.310 ± 0.058	3.416 ± 0.985♦	0.154 ± 0.030	0.767 ± 0.257
	0.241 ± 0.040^b	0.742 ± 0.322^b

^aBile duct ligation.

^b Parameter of another peak from double-peaks.

♦ p < 0.05, C_max, and AUC values of TG-SMEDDS compared with those of TG.