[This entry is marked for removal.]

From POINT Biomedical Corp
BiSphere™ is a technology for drug delivery applications by ultrasound. BiSpheres™ consists of microparticles comprising a shell of an outer layer of a biologically compatible material and an inner layer of biodegradable polymer. The core of the microbubbles contains a filling gas, liquid, or solid for use in drug delivery or as a contrast agent for ultrasonic contrast imaging. The contrast agent particles are capable of passing through the capillary systems of a subject. The drug-loaded biSpheres™ would be administered intravenously and freely circulate throughout the body, while the drug encapsulated within would remain biologically unavailable. The drug would only be released when the biSpheres become flooded when passing through an externally directed ultrasound field.
The use of biSpheres™ to transport agents to specific sites within the body is expected to substantially increase local efficacy while decreasing systemic side effects or adverse reactions. The biSpheres™ may also serve to protect labile agents from metabolism or degradation. The noninvasive release of a protected, encapsulated agent can be controlled by ultrasound imaging to a depth of 20-30 cm from the skin surface.
The flexibility in size control in the biSphere™ technology has enabled the construction of submicron ultrasound contrast agents suitable for lymphatic imaging, with a diameter in the submicron range. This agent, while much smaller in size than CardioSphere®, is based on the BiSphere configuration: a shell within a shell enclosing a gas. The inner layer, made from a biodegradable polymer, provides the physical structure and controls the acoustic response. The outer layer functions as the biological interface. Each of these layers has been independently tailored to fulfill the specific requirements for lymphatic imaging.