Preparation and in vivo pharmacokinetics of curcumin-loaded PCL-PEG-PCL triblock copolymeric nanoparticles

Figures & data

Figure 1 Structure of curcumin.

Table 1 Characteristics of nanoparticles (NPs)

NP	PEG MW (g/mol)	Feed ratio^a	MW theo^b	MW GPC^c	PDI^d	DL (%)	EE (%)
NP41	4000	1:0.5	6000	5094	1.12	8.8	70.6
NP42	4000	1:0.8	7200	5544	1.33	10.7	85.5
NP43	4000	1:1.3	9200	18,050	2.54	11.8	94.3
NP44	4000	1:2	12,000	8212	1.44	10.9	87.4
NP45	4000	1:3	16,000	14,246	1.73	10.1	80.6
NP61	6000	1:0.5	9000	6132	1.19	2.7	21.9
NP62	6000	1:0.8	10,800	19,156	2.24	9.6	76.7
NP63	6000	1:1.3	13,800	19,367	2.61	11.9	95.5
NP64	6000	1:2	18,000	23,946	2.83	11.5	91.9
NP65	6000	1:4	30,000	24,812	1.52	4.3	34.4

Notes:

a Feed weight ratio of poly (ethylene glycol) (PEG): ε-Caprolactone;

b theoretical molecular weight (MW) based on feed weight ratio;

c MW determined by gel permeation chromatography (GPC);

d polydispersity index (PDI) determined by gel permeation chromatography (GPC).

Abbreviations: DL, drug loading; EE, entrapment efficiency.

Figure 2 Synthesis of poly (ε-Caprolactone)-poly (ethylene glycol)-poly (ε-Caprolactone).

Figure 3 Fourier transform infrared spectra of poly (ethylene glycol) (A), ε-Caprolactone (B) and poly (ε-Caprolactone)-poly (ethylene glycol)-poly (ε-Caprolactone) (C).

Figure 4 Proton nuclear magnetic resonance spectrum of poly (ε-Caprolactone)-poly (ethylene glycol)-poly (ε-Caprolactone).

Figure 5 Gel permeation chromatogram of poly (ε-Caprolactone)-poly (ethylene glycol)-poly (ε-Caprolactone).

Figure 6 Particle size distribution of NP43 (blank (A) and curcumin-loaded (B)) and NP63 (blank (C) and curcumin-loaded (D)).

Figure 7 Transmission electron microscopy image of curcumin-loaded NP63.

Notes: 72,000 × magnification; scale bar is 100 nm.

Figure 8 Fourier transform infrared spectra of native curcumin (A), poly (ε-Caprolactone)-poly (ethylene glycol)-poly (ε-Caprolactone) (B), void NP63 (C), and curcumin-loaded NP63 (D).

Figure 9 Differential scanning calorimetry thermograms of native curcumin (A), void NP63 (B), and curcumin-loaded NP63 (C).

Figure 10 In vitro curcumin (CUR)-release profiles from two NPs (NP43 and NP63) at ph 5.0 at 37°C.

Figure 11 Concentration profile of curcumin (CUR) in plasma versus time after intravenous injection of CUR solution or CUR nanoparticles.

Table 2 The pharmacokinetic parameters of curcumin (CUR) solution and CUR nanoparticles (NPs) (n = 5)

Parameters	CUR solution	CUR NPs
AUC(0–∞) (mg/L*h)	668.415	2772.523
MRT(0–∞)(h)	0.168	30.07
t1/2(h)	0.135	27.618
Vss (L/kg)	0.004	0.216
CL (L/h/kg)	0.022	0.005

Abbreviations: AUC, area under the concentration–time curve; CL, total clearance; MRT, mean residence time; t_1/2, biological half-life; Vss, steady-state volume of distribution.