Multi-walled carbon nanotubes affect drug transport across cell membrane in ratastrocytes

Abstract

The impact of carbon nanotubes on the cell membrane is an aspect of particularimportance and interest in the study of carbon nanotubes’ interactions with livingsystems. One of the many functions of the cell membrane is to execute substancetransport into and out of the cell. We investigated the influence of multi-walledcarbon nanotubes (MWCNTs) on the transport of several compounds across inthe cell membrane of rat astrocytes using flow cytometry. These compounds arefluorescein diacetate, carboxyfluorescein diacetate, rhodamine 123 and doxorubicin,which are prosubstrate/substrates of multidrug transporter proteins. Resultsshowed that MWCNTs significantly inhibited cellular uptake of doxorubicin butnot the other drugs and the mode of loading made a significant difference indoxorubicin uptake. Retention of fluorescein, carboxyfluorescein and rhodamine123 was remarkably higher in MWCNT-exposed cells after an efflux period. Akinetics study also demonstrated slower efflux of intracellular fluorescein andrhodamine 123. Data presented in this paper suggest that MWCNTs could affect drugtransport across cell membranes. The implications of the findings are discussed.