Influence of polymers ratio on insulin-loaded nanoparticles based on poly-ε-caprolactone and Eudragit^® RS for oral administration

Figures & data

Table 1.  Main physicochemical properties of the unloaded nanoparticles or insulin-loaded nanoparticles prepared with different blends of Eudragit® RS and PCL. Data are shown as mean ± SD (n = 3).

Formulation	Mean diameter (nm)			Zeta potential (mV)
	Unloaded	Actrapid®	Novorapid®	Unloaded	Actrapid®	Novorapid®
RS 100%	345.7 ± 9.3	344.0 ± 8.3	479.2 ± 11.8	38.0 ± 0.5	41.0 ± 4.0	43.7 ± 1.8
RS/PCL 75/25	342.5 ± 8.1	363.4 ± 14.3	555.9 ± 4.2	37.5 ± 5.9	40.7 ± 1.8	40.7 ± 1.0
RS/PCL 50/50	339.7 ± 24.9	360.7 ± 10.6	695.2 ± 55.8	36.7 ± 1.4	41.8 ± 3.4	40.5 ± 0.7
RS/PCL 25/75	314.6 ± 5.9	322.9 ± 16.1	588.2 ± 18.9	38.5 ± 4.0	40.0 ± 2.1	38.0 ± 2.5
PCL 100%	506.0 ± 21.9	519.9 ± 34.5	505.6 ± 58.2	−17.5 ± 2.5	−9.5 ± 4.9	−15.3 ± 6.2

Table 2.  Encapsulation efficiency of insulin loaded nanoparticles prepared with different blends of Eudragit® RS and PCL. Data are shown as mean ± SD (n = 3).

Formulation	Encapsulation efficiency (%)
	Actrapid®	Novorapid®
RS 100%	96.4 ± 0.3	97.5 ± 0.1
RS/PCL 75/25	96.2 ± 0.2	96.9 ± 0.5
RS/PCL 50/50	96.3 ± 0.4	97.5 ± 0.4
RS/PCL 25/75	97.3 ± 0.4	95.4 ± 0.4
PCL 100%	95.4 ± 1.5	35.9 ± 12.2

Figure 1.  Release kinetics of Actrapid®-loaded nanoparticles prepared with different blends of Eudragit® RS and PCL. Data are shown as mean ± SD (n = 3).

Figure 2.  Release kinetics of Novorapid®-loaded nanoparticles prepared with different blends of Eudragit® RS and PCL. Data are shown as mean ± SD (n = 3).

Figure 3.  Glycemia after a single oral administration of unloaded nanoparticles (NP) and Novorapid®-loaded nanoparticles (50 IU/kg) based on Eudragit® RS and PCL (50/50). Data are shown as mean ± SEM (n = 6). Statistically different from free nanoparticles. * p < 0.05.