A time course study of cadmium effect on membrane permeability of single human bladder cancer cells using scanning electrochemical microscopy

• SECM was used to determine membrane permeability of T24 cells treated by Cd2 +.
• Cd2 + changes the T24 permeability.
• The permeability was determined by overlapping experimental and simulated PACs.
• T24 cells treated with Cd2 + displayed dramatic morphology changes.

Cd2 + is carcinogenic to both humans and experimental animals. We present quantitative time-course imaging of Cd2 +-induced variation in the membrane permeability of single live human bladder cancer cells (T24) to ferrocenemethanol using scanning electrochemical microscopy (SECM). High temporal resolution combined with non-invasive nature renders a time-lapse SECM depth scan, a promising method to quantitatively investigate the effectiveness, kinetics, and mechanism of metal ions based on the responses of single live cells in real time. Under unstimulated conditions, T24 cells have constant membrane permeability to ferrocenemethanol of approximately 5.0 × 10− 5 m/s. When cadmium is added in-situ to T24 cells, the membrane permeability increases up to 3.5 × 10− 4 m/s, allowing more flux of ferrocenemethanol to the ultramicroelectrode tip. This suggests an increased spreading between the phospholipid heads in the cytoplasmic membrane. Membrane permeability might be used as a measure to probe cell status in practical intoxication cases. The methodology reported here can be applied to many other metals and their interactions with extracellular biomolecules, leading insights into cell physiology and pathobiology.

Effects of Cd2 + on T24 cell membrane permeability have been studied by scanning electrochemical spectroscopy using depth scan imaging mode.Figure optionsDownload as PowerPoint slide