Highly efficient uptake of ultrafine mesoporous silica nanoparticles with excellent biocompatibility by Liriodendron hybrid suspension cells

Abstract

The characteristics of the interactions co-cultures of ultrafine mesoporous silica nanoparticles (MSNs) and the Liriodendron hybrid suspension cells were systematically investigated using laser scanning confocal microscope (LSCM) and scanning electron microscopy (SEM). Using fluorescein isothiocyanate (FITC) labeling, the LSCM observations demonstrated that MSNs (size, 5-15 nm) with attached FITC molecules efficiently penetrated walled plant cells through endocytic pathways, but free FITC could not enter the intact plant cells. The SEM measurements indicated that MSNs readily aggregated on the surface of intact plant cells, and also directly confirmed that MSNs could enter intact plant cells; this was achieved by determining the amount of silicon present. After 24 h of incubation with 1.0 mg mL 1 of MSNs, the viability of the plant cells was analyzed using fluorescein diacetate staining; the results showed that these cells retained high viability, and no cell death was observed. Interestingly, after the incubation with MSNs, the Liriodendron hybrid suspension cells retained the capability for plant regeneration via somatic embryogenesis. Our results indicate that ultrafine MSNs hold considerable potential as nano-carriers of extracellular molecules, and can be used to investigate in vitro gene-delivery in plant cells. Along with developments in the application of nanotechnology from animal science and medical research to plant science research, the impact of engineered nanomaterials on plant systems has attracted increasing attention, the areas including (i) the delivery of fertilizers, herbicides, pesticides and exogenous genes, (ii) the improvement of the growth of plants, and (iii) nanotoxicity research for plant cells [1][2][3][4][5][6][7][8][9][10]. However, compared with mammalian cells, the plant cell wall which is composed of cross-linked polysaccharides (cellulose, hemicelluloses, and pectin) represents an extra barrier surrounding the cell membrane that hinders the passage of nanoparticles into plant cells. To avoid the inhibiting effects of the plant cell wall, free protoplasts (which are prepared via the removal of the cell wall using cellulase treatments) have been used previously to study the internalization of various nanoparticles (e.g., CdSe/ZnS quantum dots (QDs), polystyrene nanospheres, poly(phenylene ethynelene) nanoparticles, and carbon nanomaterials) [11][12][13]. However, protoplast-based transformation methods hold disadvantages in that the viability of the protoplasts and their ability to divide are strongly reduced by the chemicals that are applied to disorganize the cell wall. For this reason, recent studies have focused on intact plant cells; it was found to that they are able to achieve endocytosis to directly internalize single-walled carbon nanotubes (CNTs), CdSe/ZnS QDs, or poly (amidoamine) dendrimer from the

Barriers, pathways and processes for uptake, translocation and accumulation of nanomaterials in plants – Critical review

“…On the other hand, small non-functionalized MSNs (5-15 nm) in suspended walled cells were able to pass through the membrane via endocytosis. This demonstrates a bias of endocytosis towards small NP size (Xia et al, 2013). As a whole, these results show that positively charged NPs 5120 nm can be internalized by CFPE.…”

Rational Design Principles for the Transport and Subcellular Distribution of Nanomaterials into Plant Protoplasts

“…There have been significant successes in the use of mesoporous silica or other nanomaterials such as carbon nanotubes to deliver nucleic acids into plant cells. Besides nucleic acids, nanoparticles can also be functionalized with molecules such as fluorescent dyes for intracellular labeling in plants, active molecules for tracking and sensing purposes, and agrochemicals for crop health .…”

Interaction of gold nanomaterials with the edible food crop, Helianthus annuus (Common sunflower)

“…in Liriodendron hybrid suspension cells were able to pass through the cell wall and membrane via cellular endocytosis. (Xia et al, 2013) Endocytosis was also the main theory because SWNT's were found in "endocytosis like" vesicles and these results are similar to mammalian cell studies. (Shen, Zhang, Li, Bi, & Yao, 2010) Plant uptake in sucrose--coated (+) TiO2--NC with diameters of 2.8 ± 1.4 nm of Arabidopsis thaliana (thale cress) leaves was studied.…”