Cellular biophysical dynamics and ion channel activities detected by AFM-based nanorobotic manipulator in insulinoma β-cells

Nanomedicine. 2013 Jul;9(5):636-45. doi: 10.1016/j.nano.2012.10.011. Epub 2012 Nov 22.


Distinct biochemical, electrochemical and electromechanical coupling processes of pancreatic β-cells may well underlie different response patterns of insulin release from glucose and capsaicin stimulation. Intracellular Ca(2+) levels increased rapidly and dose-dependently upon glucose stimulation, accompanied with about threefold rapid increases in cellular stiffness. Subsequently, cellular stiffness diminished rapidly and settled at a value about twofold of the baseline. Capsaicin caused a similar transient increase in intracellular Ca(2+) changes. However, cellular stiffness increased gradually to about twofold until leveling off. The current study characterizes for the first time the biophysical properties underlying glucose-induced biphasic responses of insulin secretion, distinctive from the slow and single-phased stiffness response to capsaicin despite similar changes in intracellular Ca(2+) levels. The integrated AFM nanorobotics and optical investigation enables the fine dissection of mechano-property from ion channel activities in response to specific and non-specific agonist stimulation, providing novel biomechanical markers for the insulin secretion process.

From the clinical editor: This study characterizes the biophysical properties underlying glucose-induced biphasic responses of insulin secretion. Integrated AFM nanorobotics and optical investigations provided novel biomechanical markers for the insulin secretion process.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biophysical Phenomena*
  • Calcium / metabolism
  • Capsaicin / pharmacology
  • Cell Line, Tumor
  • Cyclic AMP / metabolism
  • Glucose / pharmacology
  • Humans
  • Insulin / metabolism*
  • Insulin Secretion
  • Insulin-Secreting Cells / drug effects
  • Insulin-Secreting Cells / metabolism
  • Insulin-Secreting Cells / pathology
  • Insulinoma / metabolism*
  • Insulinoma / pathology
  • Ion Channels / drug effects
  • Ion Channels / metabolism
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / metabolism
  • Islets of Langerhans / pathology
  • Microscopy, Atomic Force
  • Nanotechnology / instrumentation*
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / pathology
  • Robotics / instrumentation*


  • Insulin
  • Ion Channels
  • Cyclic AMP
  • Glucose
  • Capsaicin
  • Calcium