In:
Nanomedicine, Future Medicine Ltd, Vol. 8, No. 5 ( 2013-05), p. 725-737
Abstract:
Aim: To investigate the effect of surface charge of therapeutic nanoparticles on sarcolemmal ionic homeostasis and the initiation of arrhythmias. Materials & methods: Cultured neonatal rat myocytes were exposed to 50 nm-charged polystyrene latex nanoparticles and examined using a combination of hopping probe scanning ion conductance microscopy, optical recording of action potential characteristics and patch clamp. Results: Positively charged, amine-modified polystyrene latex nanoparticles showed cytotoxic effects and induced large-scale damage to cardiomyocyte membranes leading to calcium alternans and cell death. By contrast, negatively charged, carboxyl-modified polystyrene latex nanoparticles (NegNPs) were not overtly cytotoxic but triggered formation of 50–250-nm nanopores in the membrane. Cells exposed to NegNPs revealed pro-arrhythmic events, such as delayed afterdepolarizations, reduction in conduction velocity and pathological increment of action potential duration together with an increase in ionic current throughout the membrane, carried by the nanopores. Conclusion: The utilization of charged nanoparticles is a novel concept for targeting cardiac excitability. However, this unique nanoscopic investigation reveals an altered electrophysiological substrate, which sensitized the heart cells towards arrhythmias. Original submitted 8 March 2012; Revised submitted 12 July 2012; Published online 12 November 2012
Type of Medium:
Online Resource
ISSN:
1743-5889
,
1748-6963
Language:
English
Publisher:
Future Medicine Ltd
Publication Date:
2013
SSG:
15,3
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