Disclosed is an injector assembly having driving means for injecting a substance into a subject and locking means for retaining the driving means until a predetermined amount of pressure builds in a cavity near the driving means.
CROSS REFERENCE OF RELATED APPLICATIONS
This application claims priority to, and benefit from, Russian Patent Application 99124267, filed Nov. 23, 1999, now issued as Russian Patent No. 2155015; U.S. patent application Ser. No. 09/685,633, filed Oct. 10, 2000; and U.S. patent application Ser. No. 09/685,499, filed Oct. 10, 2000. The contents of all such documents are incorporated herein by reference to the extent permitted by law.
A medical device includes a sensor that is configured to measure a property of an outer layer of an anatomical body surface. The sensor includes a source probe configured to stimulate a local surface of the outer layer of an anatomical body surface. The sensor also includes a detector configured to measure a response of the outer layer resulting from the source probe stimulation. A controller coupled to the source probe and the sensor drives the source probe using a tailored stochastic sequence and determines the property of the outer layer using the measured response received from the detector. The sensor can be used with medical devices, such as drug delivery devices including microneedle transport devices and needleless injection devices.
An injector includes a housing having a chamber for holding a liquid formulation of an active principle to be injected into a biological body and an output port in fluid communication with the chamber through which the liquid formulation is injected. A piston is positioned within the housing, and includes an end portion with substantially the same shape as the chamber. A magnetic force draws the piston and housing together to expel the liquid formulation out of the chamber through the output port.
