pH and temperature dual-sensitive liposome gel based on novel cleavable mPEG-Hz-CHEMS polymeric vaginal delivery system

Figures & data

Figure 1 A schematic diagram of the strategy of mPEG-Hz-CHEMS cleavable dual-sensitive liposome gels.

Abbreviation: mPEG-Hz-CHEMS, methoxy polyethylene glycol 2000-hydrazonecholesteryl hemisuccinate.

Table 1 The physicochemical parameters of AC-loading pH-sensitive liposomes and plain AC liposomes

Parameters	Plain liposomes	pH-sensitive liposomes
Entrapment efficiency (%)	88.9 ± 4.4	93.8 ± 3.2
Particle size (nm)	118.9 ± 5.6	126.6 ± 3.8
Zeta potential (mv)	−21.9 ± 2.6	−18.1 ± 2.3

Abbreviation: AC, arctigenin.

Figure 2 The structure and ¹H-NMR spectra of mPEG-Hz-CHEMS in CDCl₃.

Figure 3 FT-IR spectra of blank gels (A), AC liposomes (B), AC dual-sensitive gels (C).

Abbreviation: AC, arctigenin.

Figure 4 DSC curves of AC (A), AC liposomes (B), AC dual-sensitive gels (C).

Abbreviation: AC, arctigenin.

Figure 5 The sol-gel transition observation of AC dual-sensitive gels over the gelation temperature (A), gelation (B), and under the gelation temperature (C).

Abbreviation: AC, arctigenin.

Figure 6 pH-sensitive profiles of AC dual-sensitive gels (n = 3).

Abbreviation: AC, arctigenin.

Figure 7 In vitro release of AC dual-sensitive gels at pH 5.0, 7.4 and 9.0.

Abbreviation: AC, arctigenin.

Figure 8 Cytotoxicity of AC dual-sensitive gels.

Notes: Data represent the mean ± SD (n = 6). *P < 0.05, compared with the free AC.

Abbreviation: AC, arctigenin.