Surface-modified gatifloxacin nanoparticles with potential for treating central nervous system tuberculosis

Figures & data

Table 1 Nanoparticle formulations developed

Formulation	Rhodamine (mg)	Gatifloxacin (mg)	Polysorbate 80 (%)	Labrafil (mg)
NPR1	2.5	–	–	–
NPR2	2.5	–	1	–
NPR3	2.5	–	–	3.5
NPB1	–	–	–	–
NPB2	–	–	1	–
NPB3	–	–	–	3.5
NPG1	–	5	–	–
NPG2	–	5	1	–
NPG3	–	5	–	3.5

Table 2 Characteristics of the nanoparticle formulations prepared

Formulation	Mean particle size ± standard deviation (nm)	ζ-Potential ± standard deviation (mV)	Encapsulation efficiency ± standard deviation (%)
NPR1	234.8±4.3	–	55.3±0.4
NPR2	194.9±5.7	–	51.3±0.3
NPR3	237.8±11	–	60.9±0.4
NPB1	150.5±5.1	−23±1.3	–
NPB2	98.9±9.6	−19.1±1.1	–
NPB3	156.3±6.1	−17.3±1	–
NPG1	176.6±11.6	−18.6±0.4	34.1±0.1
NPG2	176.5±2.9	−20.1±1.1	28.2±0.2
NPG3	182.9±2.5	−19.3±0.8	10.4±1.1

Table 3 Brain biodistribution of rhodamine solution and rhodamine-loaded nanoparticles

Formulation	Fluorescence intensity, mean ± standard deviation
	30 minutes		60 minutes
	Hippocampus	Cortex	Hippocampus	Cortex
Rhodamine solution	13.77±1.39	10.78±1.11	9.79±1.57	3.13±1.53
NPR1	19.95±1.69	16.99±3.48	10.31±1.83	9.22±2.05
NPR2	29.72±1.05	17.56±3.42	30.26±2.13	31.36±1.95
NPR3	29.61±2.45	18.09±2.11	21.35±1.71	26.25±2.83

Figure 1 Confocal microscopy images of the cerebral cortex.

Notes: Control (A), NPR1 (B), NPR2 (C), and NPR3 (D) obtained at 30 minutes. Control (E), NPR1 (F), NPR2 (G), and NPR3 (H) obtained at 60 minutes.

Figure 2 Neuronal cells corresponding to control and treated animal groups (A). Hippocampus sections obtained for control and treatment groups (B): images obtained at 30 minutes for control group treated with Rhodamine solution (a), group trated with formulation NPR1 (b), group treated with formulation NPR2 (c), and group treated with formulation NPR3 (d). Imaged obtained at 60 minutes for control group (e), group treated with formulation NPR1 (f), group treated with formulation NPR2 (g), and group treated with formulation NPR3 (h).

Figure 3 Mean concentrations of rhodamine (Rh) ± standard deviation.

Notes: In the liver and lungs at 30 minutes (A) and 60 minutes (B) after administration of Rh-PLGA NPs. NPR1, Rh-PLGA NPs; NPR2, Rh-PLGA NPs prepared with polysorbate 80; NPR3, Rh-PLGA NPs prepared with Labrafil.

Abbreviations: PLGA, poly(lactic-co-glycolic acid); NPs, nanoparticles.

Figure 4 Scanning electron microscopy images and mean in vitro release profiles of Gat.

Notes: From Gat-loaded PLGA NPs (NPG1) (A), Gat-loaded PLGA NPs prepared with polysorbate 80 (NPG2) (B), and Gat-loaded PLGA NPs prepared with Labrafil (NPG3) (C).

Abbreviations: Gat, gatifloxacin; PLGA, poly(lactic-co-glycolic acid); NPs, nanoparticles.