Abstract: A nanosensor for detecting and quantifying lactate in different types of samples, such as tissues, intra-cellular and subcellular compartments, with high spatial and temporal resolution is disclosed. Methods comprising use of the nanosensor for quantifying the activity of lactate transporters, rates of cellular lactate production and cellular lactate consumption, and rate of mitochondrial pyruvate consumption are also disclosed. Methods for quantifying the transformation in energy metabolism that characterizes cancer cells with single-cell resolution and for detecting interference of candidate drugs with mitochondrial energetics are additionally disclosed.

Abstract: The present invention relates to a new optical tool for detecting and quantifying pyruvate in samples, in tissues and in cellular and subcellular compartments, with high spatial and temporal resolution, this is a Forster Resonance Energy Transfer (FRET)-based pyruvate sensor comprising a bacterial PdhR transcription factor between any suitable donor and acceptor fluorescent proteins moieties. The invention also relates to methods of use of this novel optical tool for the quantification of the activity of pyruvate transporters, for the quantification of the rates of cellular pyruvate production and consumption, and for the direct quantification of the rate of mitochondrial pyruvate consumption in intact cells.

Abstract: A nanosensor for detecting and quantifying lactate in different types of samples, such as tissues, intra-cellular and subcellular compartments, with high spatial and temporal resolution is disclosed. Methods comprising use of the nanosensor for quantifying the activity of lactate transporters, rates of cellular lactate production and cellular lactate consumption, and rate of mitochondrial pyruvate consumption are also disclosed. Methods for quantifying the transformation in energy metabolism that characterizes cancer cells with single-cell resolution and for detecting interference of candidate drugs with mitochondrial energetics are additionally disclosed.

Abstract: A method to measure the metabolic rate or rate of glucose consumption of cells or tissues with high spatiotemporal resolution using a glucose nanosensor is disclosed. The method generally includes providing single cells or cell populations, cells in suspension or adherent, in a cell culture, a tissue culture, a mixed cell culture, a tissue explant, or in animal tissues in vivo for the measurement of glucose metabolic rate; expressing a glucose sensor in individual cells; calibrating the sensor in controlled conditions; disrupting the steady-state of glucose entering the cell; recording the output from the sensor and calculating the corresponding glucose concentration at different times; and determining the glucose metabolic rate. The method can be applied for the screening of molecules with pharmacological potential, determination of glucose rate of cancerous cells, tissue physiology and biochemistry research.