Cellular uptake and gene delivery using layered double hydroxide nanoparticles

Abstract

The cellular uptake of narrowly dispersed LDH {[Mg 3 Al(OH) 8 ](CO 3 ) 0.5 } nanoparticles into the Mouse Motor Neuron (NSC 34) cell line has been studied. The effect of LDH concentration and incubation time on the cellular uptake was investigated using fluorescein isothiocyanate (FITC) labelled LDH nanoparticles. We observed that cellular uptake increases with the increased LDHs concentration and incubation time.Confocal laser microscopy and transmission electron microscopy reveal that 20 nm LDHs nanoparticles intrude into the cytoplasm and then enrich in the cellular nucleus, while nanoparticles greater than 20 nm only locate in the cytoplasm. The 20 nm sized LDHs nanoparticles display similar uptake to both the cytoplasm and nucleus, and show little cytotoxicity with no significant decrease in NSC 34 cell proliferation and viability below 200 mg ml À1 . DNA modified 20 nm LDH nanoparticles are successful in transfection of the pEGFP-N1 DNA plasmid to NSC 34 cells.

Inorganic nanolayers: structure, preparation, and biomedical applications

“…162 The study revealed that cellular uptake was directly proportional to LDH concentration and incubation time. They also found that LDHs of 20 nm size were better at internalizing in the cell cytoplasm and cell nucleus; however, LDHs greater than 20 nm were internalized in the cell cytoplasm.…”

“…They also found that LDHs of 20 nm size were better at internalizing in the cell cytoplasm and cell nucleus; however, LDHs greater than 20 nm were internalized in the cell cytoplasm. 162 …”

“…162 The free FITC anions showed very weak green fluorescence at a much higher concentration of 6.25 mg⋅mL −1 compared to CO 3 LDH-FITC. The lower free FITC cytoplasm entrance can be attributed to the mechanism of entrance: free FITC entrance takes place due to diffusion and not by endocytosis.…”

Particle size- and number-dependent delivery to cells by layered double hydroxide nanoparticles

“…Choy et al [11] also found dose dependent uptake of LDH-FITC NPs by NIH 3T3 cells in the test concentration range (<45 lM). Li et al [50] reported concentration dependent uptake of 65 nm CO 3 LDH-FITC by NSC 34 cells in the concentration range of 6.25-100 lg/mL, where FITC was adsorbed onto the surface of CO 3 -LDH instead of intercalated into the interlayers.…”

“…This could be caused by several vague parameters without clear and consistent definition. The first one is NP size, which is normally characterised as the Z-average hydrodynamic diameter (measured by light scattering technology) [29,41,50] or the number average size (measured and statistically calculated from TEM or SEM images) [6,28]. The second term is the dose of nanoparticle.…”