Preparation, characterization, and in vivo evaluation of tanshinone IIA solid dispersions with silica nanoparticles

Figures & data

Figure 1 The dissolution profiles of TSIIA and SDs and PMs prepared using different ratios of TSIIA/silica nanoparticles (1:1, 1:3, 1:5, and 1:7 SDs and 1:5 PMs).

Note: Each point represents the mean ± standard deviation (n = 3).

Abbreviations: PMs, physical mixtures; SDs, solid dispersions; TSIIA, tanshinone IIA.

Figure 2 Scanning electron microscopy photomicrographs of (A) TSIIA and (B) SDs prepared using a TSIIA/silica nanoparticles ratio of 1:5.

Abbreviations: SDs, solid dispersions; TSIIA, tanshinone IIA.

Figure 3 Differential scanning calorimetry curves of pure TSIIA (A), silica nanoparticles (B), and PMs (C) and SDs prepared at a TSIIA/silica nanoparticles ratio of 1:5 (D).

Abbreviations: Exo, exothermic direction; PMs, physical mixtures; SDs, solid dispersions; TSIIA, tanshi-none IIA.

Figure 4 The X-ray powder diffractograms of TSIIA (A), silica nanoparticles (B) and PMs (C) and SDs with a TSIIA/silica nanoparticle ratio of 1:5 (w/w) (D).

Abbreviations: PMs, physical mixtures; SDs, solid dispersions; TSIIA, tanshinone IIA; w/w, weight by weight.

Figure 5 The IR spectra of TSIIA (A), silica nanoparticles (B) and PMs (C) and SDs with a TSIIA/silica nanoparticle ratio of 1:5 (w/w) (D).

Abbreviations: IR, infrared; PMs, physical mixtures; SDs, solid dispersions; TSIIA, tanshinone IIA; w/w, weight by weight.

Table 1 Stability test of SDs $(\text{n}=6,\overline{x}\pm \text{s})$

Samples	0 months		6 months
	Drug content (%)	Dissolution rate (%) (1 h)	Drug content (%)	Dissolution rate (%) (1 h)
1:5 SDs	16.52 ± 0.23	92.10 ± 1.94	16.19 ± 0.73	89.64 ± 1.87

Abbreviations: h, hours; SDs, solid dispersions.

Figure 6 The mean plasma concentration-time curve of TSIIA in rats after oral administration of SDs, PMs, and TSIIA equivalent to 60 mg kg⁻¹ of TSIIA (n = 6).

Notes: The values are represented as the mean ± standard deviation (n = 6/group/time point).

Abbreviations: PMs, physical mixtures; SDs, solid dispersions; TSIIA tanshi-none IIA.

Table 2 The main pharmacokinetic parameters of TSIIA after oral administration of TSIIA, PMs or SDs in rats (n = 6) at a dose of 60 mg/kg

Parameters	Pure TSIIA	PMs	SDs
Tmax(h)	2.56 ± 0.447	2.39 ± 0.495	1.58 ± 0.325*
Cmax (ng/mL)	72.78 ± 6.593	76.1 ± 8.169	152.34 ± 16.281*
t1/2(h)	4.38 ± 0.758	4.20 ± 0.726	3.75 ± 0.533
AUC0–t (h ng/mL)	379.50 ± 58.942	398.85 ± 66.538	862.47 ± 81.594*
AUC0–⊥ (h ng/mL)	416.69 ± 62.439	439.63 ± 70.145	914.79 ± 94.175*
Relative bioavailability(%)	–	105.1	227.3

Notes: Data are expressed as the mean ± standard deviations (n = 6);

* P < 0.01 versus 60 mg/kg TSIIA.

Abbreviations: AUC, area under the plasma concentration-time curve; C_max, maximum plasma concentration; h, hours; PMs, physical mixtures; SDs, solid dispersions; t_1/2, half-life; T_max, time to reach C_max; TSIIA, tanshinone IIA.