"The device can be programmed to deliver a range of doses to various depths — an improvement over similar jet-injection systems that are now commercially available."

"While there are several jet-based devices on the market today, Hogan notes that there are drawbacks to these commercially available devices. The mechanisms they use, particularly in spring-loaded designs, are essentially “bang or nothing,” releasing a coil that ejects the same amount of drug to the same depth every time."

“Commercially available jet injectors … provide limited control, which limits their applications to certain drugs or patient populations,” Mitragotri says. “[This] design provides excellent control over jet parameters, including speed and doses … this will enhance the applicability of needleless drug devices.”

Read more at MIT News: http://web.mit.edu/newsoffice/2012/needleless-injections-0524.html