Granted Patent
Utility
US 5,693,228 · App. 08/534,936
Method and device for vibration during solid phase microextraction
Inventors:
Wulf Hinrich Koehler, Helmut Geppert
Patented Case
View Patent ↗
Granted: Dec 2, 1997
Filed: Sep 28, 1995
Inventors
Wulf Hinrich Koehler
Helmut Geppert
Assignee (at issue)
Varian, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.