Visualization and detection of live and apoptotic cells with fluorescent carbon nanoparticles

Abstract

Apoptosis is a genetically encoded cell death program that involves different processes occurring on molecular and sub-cellular levels. Here we report on its new features—the increased accumulation of fluorescent carbon nanoparticles (CDots) in cells and their changed distribution within cell interior, which can witness on altered mechanisms of their translocation through the membrane. The comparative studies of living (intact) and apoptotic cells were provided with two cell lines (HeLa, Vero) using two types of fluorescent nanoparticles (“violet” and “blue” CDots). In all studied cases the images of living and apoptotic cells were different; the apoptotic cells incorporated larger number of CDots resulting in their much brighter images. These nanoparticles are distributed in cell cytoplasm, however, when the cells are fixed and treated with detergent, their nucleus is also labeled. Flow cytometry allows distinguishing the sub-populations of living and apoptotic cells in their cultures and suggests a very cheap and easy way to characterize them.Electronic supplementary materialThe online version of this article (doi:10.1186/s12951-015-0148-7) contains supplementary material, which is available to authorized users.

Interaction and cellular uptake of surface-modified carbon dot nanoparticles by J774.1 macrophages

“…Because PB groups can be used to target SA ligands on diseased cells, PB-conjugated Cdots could potentially be used as molecular imaging probes and drug delivery agents targeting diseased cells such as tumor cells. Our observation that Cdots exert minimal toxicity in J774.1 cells corroborates previous findings in other cell types [ 5 , 12 , 15 ]. To our knowledge, this is the first study to investigate the interaction between Cdot nanoparticles and macrophages.…”

“…The toxicity of Cdots in vitro has only been tested in non-immune cell lines such as HeLa [ 12 , 15 ], MCF-7 [ 5 ], MDA-MB231 [ 5 ], Vero [ 15 ], and L929 [ 16 ]. Therefore, we tested the toxicity of Cdots in J774.1 macrophages after 24 h of exposure to various Cdot preparations using the MTT assay, a colorimetric assay that measures the metabolic activity of cells.…”

Facile fabrication of luminescent organic dots by thermolysis of citric acid in urea melt, and their use for cell staining and polyelectrolyte microcapsule labelling

“…5 and Figures S20–22 (Supporting Information File 1) for fixed and pristine (alive) cells, respectively. It is well known that cellular staining with fluorescent carbon dots is typically more effective for pre-fixed cells [52]. Data obtained indicate that the normal intact ST-cells were stained with O-dots (50 μg/mL) diffusely, and cellular luminescence was weak (Fig.…”

Effective delivery of hydrophobic drugs to breast and liver cancer cells using a hybrid inorganic nanocarrier: A detailed investigation using cytotoxicity assays, fluorescence imaging and flow cytometry

“…Given that the IC50 values obtained for the drug loaded nanoparticles over MCF-7 and HEpG2 cells are very much lower compared to the reported work it appears that these formulations are much safer for therapeutic use than the pure drugs. The cytotoxic effects caused by our nanoparticles on Vero cells are very low when compared with the reported work carried out using carbon nanotubes (CNTs) and Al 2 O 3 nanoparticles [62], [63].…”