Development of liver-specific ribavirin-loaded nanoparticles with reduced cytotoxicity

Figures & data

Figure 1. Ionic interactions of nanoparticle components. (a) A nanoparticle developed previously consisting of RMP, AG-PLL, and PLA with terminal carboxyl groups (PLA-C). (b) A nanoparticle developed in this study consisting of RMP, AG-PLG, and PLA with terminal amino groups (PLA-N1 or PLA-N3). The components in dotted line squares were cationic, and those in solid line squares were anionic. Allows mean ionic interactions. (c) Chemical structures of PLA, RMP, AG-PLL and AG-PLG.

Table 1. Molecular weights of polymers

Code	Mw	Mn	Mw/Mn
PLG	31,100	21,000	1.48
AG-NH2	16,700	14,200	1.18
AG-PLG	140,600	67,200	2.09

Table 2. Nanoparticle characteristics

Code	Coating polymer	Core polymer	ζ-potential (mV)	Diameter (nm)	RMP loading efficiency (wt.%)
None/C-NP	None	PLA-C	−43.4	107	N.D.
None/N1-NP	None	PLA-N1	−0.1	167	N.D.
None/N3-NP	None	PLA-N3	5.1	143	N.D.
PLG/N1-NP	AG-PLG	PLA-N1	−5.5	158	0.1
PLG/N3-NP	AG-PLG	PLA-N3	−4.1	88	0.6
PLL/C-NP	AG-PLL	PLA-C	0.0	77	0.8

Notes: The diameters and ζ-potentials were measured three times and the mean values were shown. N.D.: not determined.

Figure 2. Release behavior of RMP from PLG/N3-NP.

Note: Each data point represents the mean ± SD of measurements from three individual nanoparticle suspensions.

Figure 3. Uptake of rhodamine-loaded nanoparticles in HepG2 cells.

Note: Merged images of rhodamine and Hoechst staining are shown on the left, and merged images of rhodamine and bright field microscopy are shown on the right.

Figure 4. Cytotoxicity of conjugates.

Notes: HepG2 cells were incubated with conjugates in DMEM with FBS or in Opti-MEM without FBS for 24 h. Each data point represents the mean ± SD of measurements from three individual wells. The double asterisks indicate significance at p < 0.01 vs. AG-PLG.

Figure 5. Cytotoxicity of nanoparticles. After incubation of HepG2 cells with various nanoparticles in Opti-MEM for 24 h, (a) cell viability was determined, or (b) the cells were observed using a microscope. Each data point represents the mean ± SD of measurements from three individual wells.

Note: The double asterisks indicate significance at p < 0.01 vs. PLG/N3-NP.

Figure 6. Frozen liver sections of mice.

Note: Merged images of bright field microscopy and rhodamine are shown at the top, and images of rhodamine are shown on the bottom.