Observing biophysical properties of swine myocardium and mitochondria with tapping mode scanning probe microscope

Abstract

Single ventricular myocytes and mitochondria were isolated from swine hearts follow enzymatic dissociation procedures. Experiments were carried under tapping mode AFM with 125&55¦ÍÌm scanner and Si3N4 probes at 340–430 kHz. High resolution AFM data of single myocytes and mitochondria were collected simultaneously which show ultrastructure features including striated pattern of contractile proteins, sarcoplasmic reticulum and mitochondria. From the images, we reached longitudinal columns of contractile proteins which separated by valleys, and surface invaginations separated by transverse tubules which dip into the fiber interior and mitochondria were compressed between the contractile machinery which abundant in myocardium to provide energy. These images show that there is a consistent relationship between grooves and Z lines which clue to Z line must be attached firmly to plasmolemma. At last, we have tried to do some research by putting the samples into different physiological buffer and the similar results can be collected but lacking of enough equilibrium. And the CM‐AFM experiments intended to appear the damage of cantilever and the biological sample, so we selected the TM‐AFM rather than the CM‐AFM.