A team of researchers at the University of Toronto is developing a new form of microbubble delivery. Typically when the microbubble bursts, the drugs that lie within the gaseous chamber or within the bubble's membrane are released. But the rate of uptake into diseased tissues is low. The Toronto team is deploying ultrasound to implode the bubbles into several smaller nanobubbles that can cross biological barriers due to their size and release the payloads within the target area. The team showed that the implosion into nanobubbles can be triggered to occur inside the body itself. Ultrasound is already used in conjunction with microbubbles to image blood vessels and organs. The bottom line is that in drug delivery, smaller is better. With diameters of 5 to 500 nanometers, the nanobubbles can be anywhere from 2 to 2,000 times smaller than the microbubbles. Story