Nanosqueezed light for probing mitochondria and calcium-induced membrane swelling for study of neuroprotectants
We report a new bioMEMs nanolaser technique for measuring characteristics of small organelles. We have initially applied the method to study mitochondria, a very small (500nm to 1um) organelle containing the respiration apparatus for animal cells. Because the mitochondria are so tiny, it has been difficult to study them using standard light microscope or flow cytometry techniques. We employ a recently discovered a nano-optical transduction method for high-speed analysis of submicron organelles. This ultrasensitive detection of submicron particles uses nano-squeezing of light into photon modes imposed by the ultrasmall organelle dimensions in a submicron laser cavity. In this paper, we report measurements of mitochondria spectra under normal conditions and under high calcium ion gradient conditions that upset membrane homeostasis and lead to organelle swelling and lysis, similar to that observed in the diseased state. The measured spectra are compared with our calculations of the electromagnetic modes in normal and distended mitochondria using multiphysics finite element methods.