Ultrafast Probe of Cell and Organelle Physiology by Intracavity Micro/Nano Laser Spectroscopy

Healthy cells and organelles rely on a complex of trans-membrane processes to regulate internal molecular composition and function for normal cellular respiration. A key to cell health is the maintenance of a stable osmotic equilibrium. In the diseased cell state, this equilibrium is altered by changes in the membrane potential and alteration of the internal biomolecular composition. These changes in equilibrium in individual cells can be rapidly probed by novel intracavity micro/nanolaser spectroscopy and microscopy techniques that exploit intrinsic optical polarizability of biomolecules. This talk reports studies of the transformation of intra-cellular and isolated mitochondria from the normal to disease state in normal and transformed (to cancer) mouse liver cells. Intracavity laser spectroscopy reveals dramatic changes in the cell and organelle osmotic equilibrium. Mitochondrial correlation microscopy details a transition from aerobic to anerobic respiration. Changes in molecular composition are confirmed by UV absorption and luminescence excitation spectroscopy. The results confirm the unique ability of intracavity micro/nano spectroscopy to rapidly assess changes arising from altered biomolecular states of cells and organelles.