Journal of Materials Chemistry B
Paper
suggest a beneficial effect on cells, by the cholesteryl group T. P. Davis is grateful for the award of an Australian Laureate
(vs. solely the trisulfide group). Fellowship from the ARC (FL140100052) and J. F. Quinn for an ARC
– Using Alamar Blue assay, a cyto-protective effect was Future Fellowship (FT170100144). The authors acknowledge sup-
demonstrated by T (against C-induced cytotoxicity and against port from the Australian Research Council (DP170102950) and the
D-induced cytotoxicity). However, for P, a protective effect was Monash University Institute of Pharmacy and Pharmaceutical
only demonstrated against D, but not against C. These results, Sciences (MIPS).
demonstrating cyto-protection, also support the notion that the
cholesteryl group has an important role to play, and that the
trisulfide group is not solely implicated. The protective effect
was found for P (against D-induced toxicity vs. C-induced
Notes and references
toxicity) is likely due to the reaction of generated H2S
with disulfides, which produces reactive persulfides, such as
CHOL-SSH. These could also be pertinent mediators involved
in cyto-protection as they are also produced in the case of T.
– Membrane effects: membrane destabilization and/or destruc-
tion are events that could take place when a self-assembled surfac-
tant encounters cells. The CMC value of C (B13 mg mLꢀ1) indicates
a tendency of C to interact with the membrane, whether T and D,
with degradable structures and with CMC values significantly higher
(67 and 90 mg mLꢀ1 respectively), are less likely to do so. Membrane
permeabilization does not account for the toxic effect of C, as
demonstrated by propidium iodide test. However, by way of ratio-
metric imaging, using the lipophilic dye (Laurdan), membrane
perturbation was instead demonstrated for C. Both D and C
were also found to cause cells to depart from their normal cell
morphology, indicating a physical interaction with the cell
membrane, with potential consequences on cell viability.
– ROS generation: a comparison of ROS levels to basal levels,
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Conflicts of interest
There are no conflicts to declare.
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Acknowledgements
This work was carried out within the ARC Centre of Excellence in
Convergent Bio-Nano Science and Technology (CE140100036).
J. Mater. Chem. B
This journal is © The Royal Society of Chemistry 2020