Abstract: A method and system are provided for detection of localized hydrogen peroxide within tissue by introducing a catalase-containing material into at location of interest, positioning an ultrasound transducer over the location, and generating an ultrasound image to detect microbubbles, where the presence of microbubbles indicate the presence of localized hydrogen peroxide. The catalase-coated surface may be the inner surface of a microtube, on the surface of or incorporated within a nanosphere or microsphere, or an implantable device.

Abstract: Provided herein, inter alia, are compositions, methods of detecting a diseased tissue in a subject, and methods of treating a subject having cancer.

Abstract: A method and system are provided for detection of localized hydrogen peroxide within tissue by introducing a catalase-containing material into at location of interest, positioning an ultrasound transducer over the location, and generating an ultrasound image to detect microbubbles, where the presence of microbubbles indicate the presence of localized hydrogen peroxide. The catalase-coated surface may be the inner surface of a microtube, on the surface of or incorporated within a nanosphere or micro sphere, or an implantable device.

Abstract: Provided herein is a method for enzymatically triggered assembly of polymeric nanostructures for detection of cancer-associated enzymes in vivo. By detecting enzymatic signals associated with disease, one can sensitively determine the site, and extent of disease within a patient.

Abstract: A method for imaging leverages the fluorescence lifetime of a fluorescent Si-containing particle to distinguish from background fluorescence. A particle is introduced into tissue. An excitation light pulse is applied to excite luminescence from the fluorescent Si-containing particle. Time-gated measuring of a responsive luminescence signal identifies the particle. In preferred embodiments the particle is coated or encapsulated with an organic material. The fluorescence lifetime of particles can be controlled during manufacture, such as by oxidation levels, quenching treatments, or by aging. This permits introducing and using groups of particles in imaging that have unique lifetimes and multiple time gating can be used to identify different particles or to monitor the change in lifetime of a single set of particles as they respond to a biochemical stimulus. The particles can also be functionalized for affinity to particular tissues and can be loaded with treatment molecules.