There's an extensive review article entitled Bloodless Glucose  Measurements in Critical Reviews in Therapeutic Drug Carrier Systems, 15(3):199-241 (1998).
  It reviews many methods for minimally or non-invasive blood glucose  monitoring.  Towards the end of the article it provides a short  description of a few devices and mentions many companies - Sprectrx, Integ, Technological Chemicals and Products, Cygnus, Non-Invasive Monitoring Company, Endodermic Medical Technologies Company, Neurometrix, Sontra Medical, Mini-med, Biocontrol Technology, Futrex, etc.  |