yes / Nanoparticles are increasingly used in industry and medicine due to their unique physiochemical
properties such as their small size, charge, shape, chemical architecture, large surface area, surface reactivity and
media interactions, etc [1-5]. However, very little is still known on the interactions between nanoparticles and the
biological system. This study aims to evaluate the cytotoxicity of polystyrene latex bead nanoparticles on HaCat and
HeLa cell lines. Carboxyl-modified 20 nm polystyrene NPs core labelled with fluorophore were from Invitogen. We
chose to use polystyrene NPs because this specific type of NP is being increasingly characterized for use in
nanosensors and drug nanocarrier investigations. 1x 104 cells/100 μl of cell culture medium were plated into 96-well
plates in triplicate, measuring activity post 24 hours at concentrations of 10, 50, 100 μg/ml of polystyrene NPs
exposure. The extracellular lactate dehydrogenase release was measured by using a colorimetric CytoTox 96
nonradioactive assay kit from Promega and the absorbance were recorded at 450nm (FLUO-star) with Elisa micro
plate reader. The MTT assay was used to evaluate mitochondrial activity. This was performed by inserting a premixed
optimized dye solution in the culture wells. The Absorbance was recorded at 570 nm, from the recorded absorbance is
directly proportional to the number of live cells. The cell lines were kept in a plastic T-75cm2 tissue culture flasks
grown in DMEM.
We found that cytotoxicity of polystyrene NPs on both cells was concentration dependent. For Hela cells, with
exporesure of polystyrene NPs at concentrations of 10, 50, 100 μg/ml for 24 hrs, the percentage cytotoxicity of
positive control for LDH assay was 35.9%, 49.5% and 73.4% respectively. With the MTT cell viability assay the
percentage MTT reduction of negative control was 88.9%, 42.9% and 26.4% respectively. Cell toxicity increased with
increasing polystyrene NPs concentration. For HaCaT cells, the cytotoxic effect is less significant than those on Hela
cells. With MTT assay, when compared to HaCaT cells exposed to a negative control containing only PBS, the cell
viability decreased as the concentrations of NPs increased. Cells exposed to 100μg/ml of polystyrene NPs for a period
of 24 hours compared to those exposed to a positive control (100% cell viability) had an average cell viability of 49%,
with those numbers decreasing from 59% for cells exposed to 10μg/ml of polystyrene NPs to 57% for cells exposed to
50μg/ml of polystyrene NPs.
Our results indicated that polystyrene NPs acted differently in two different cell types and that cautions should be
taken about its cytotoxicity. Further understanding of the mechanism involving the ROS generation could provide more
information on how polystyrene NPs increase cytotoxicity.
| Identifer | oai:union.ndltd.org:BRADFORD/oai:bradscholars.brad.ac.uk:10454/10911 |
| Date | January 2016 |
| Creators | Phillip, Roy, Zahid, Myra, Shang, Lijun |
| Source Sets | Bradford Scholars |
| Language | English |
| Detected Language | English |
| Type | Abstract, Accepted Manuscript |
| Rights | © 2016 The Authors. Published by the Physiological Society. Reproduced in accordance with the publisher's self-archiving policy. |
| Relation | http://www.physoc.org/proceedings/abstract/Proc%20Physiol%20Soc%2037PCA139 |
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