Andrographolide nanoparticles in leishmaniasis: characterization and in vitro evaluations

Figures & data

Table 1 Characterization of AGnp preparations

AGnp preparations	Particle size (nm)	Zeta potential (mV)	PDI	Entrapment efficiency %
Formulation A	426 ± 21.2*	−22.2 ± 2.1	0.155 ± 0.03	59 ± 4.4**
Formulation B	173 ± 12.6*	−34.8 ± 1.4	0.229 ± 0.01	80 ± 3.5*
Formulation C	225 ± 18.4	−34.2 ± 1.8	0.468 ± 0.02	56 ± 5.2

Notes: Results expressed as mean ± SD (n = 4);

* P < 0.01 significant difference compared with Formulation C;

** P < 0.5 no significant difference compared with Formulation C.

Abbreviations: AGnp, andrographolide nanoparticles; PDI, polydispersity index.

Figure 1 Andrographolide (AG) and andrographolide nanoparticles (AGnp) in water medium. A) AG flakes insoluble in water. B) AGnp (Formulation B) colloid in water.

Figure 2 Atomic force microscopy study of andrographolide nanoparticles. A) Single particle 3D surface topography. B) 2D study of particle distribution (Formulation B).

Figure 3 A) Fourier transform infrared overlay of entire region. B) Overlay at C—OH region. C) Overlay at C—OH region and CH2 region. Color codes: andrographolide (AG), blue; polyvinyl alcohol/poly(DL-lactide-co-glycolic acid) (PVA/PLGA), brown; AG/PVA/PLGA, green.

Figure 4 In vitro release profile of andrographolide nanoparticle preparations. Results expressed as mean ± SD (n = 3).

Figure 5 Atomic force microscopy of andrographolide (AG) nanoparticles before and after dissolution. A) Formulation B before release. B) Formulation B, 600 hours after AG release.

Table 2 Korsemeyer–Peppas release kinetics modeling for AGnp

AGnp preparation	Korsemeyer–Peppas model parameters
Formulation A	n = 0.26	K = 0.19
Formulation B	n = 0.33	K = 0.09
Formulation C	n = 0.29	K = 0.09

Abbreviation: AGnp, andrographolide nanoparticles.

Figure 6 Andrographolide nanoparticles in macrophages under fluorescence microscope after 2 hours’ incubation.

Table 3 Antileishmanial activity of AG, AGnp, and standard antileishmanial agents against L. donovani

Activity (IC50 ± SD or CC50) in μM concentrations
Drug tested	Axenic amastigote (IC50 ± SD)	Amastigote in macrophage (IC50 ± SD)	Cytotoxicity assay (CC50)
Formulation A	64 ± 8*	54 ± 5*	>1.2 × 10^3
Formulation B	36 ± 4*	28 ± 2*	>2 × 10^3
Formulation C	76 ± 6*	62 ± 8*	>1.8 × 10^3
Andrographolide	160 ± 26	141 ± 21	>10^3
Stibogluconate	410 ± 60*	246 ± 37**	>2.4 × 10^3
Amphotericin B	0.2 ± 0.1*	0.15 ± 0.1*	>13

Notes: Results expressed as mean ± SD (n = 3);

* P < 0.01 significant difference compared with AG;

** P < 0.05 no significant difference compared with AG.

Abbreviations: AG, andrographolide; AGnp, andrographolide nanoparticles; IC₅₀, inhibitory concentration 50%; CC₅₀, cytotoxicity concentration 50%.