Patent Yard Sign in
Expired Canadian patentCanada

Hair analysis method

CA 2133560 C · Owner: Psychemedics Corporation · Inventors: Baumgartner, Werner A.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A method for the direct analysis of analyte indicative of marijuana exposure found in keratinized structures, e.g. hair fingernails, and toenails, which comprises preparing a mixture containing dithiothreitol or dithioerythritol, a protease suitable for the digestion of the keratin structure and a sample of the keratin structure; permitting the enzyme to at least substantially digest the sample of keratin structure to form a digest solution, followed by mixing the digest solution with a suspension of an ion exchange resin to remove an interfering cross, reacting substance naturally found in hair and finally subjecting the digest solution to analysis to determine the identity and amount …

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed February 1, 1994 and granted January 15, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 1, 2014.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 1, 2016.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledFebruary 1, 1994
GrantedJanuary 15, 2002
Term endedFebruary 1, 2014
Patent numberCA 2133560 C
Classification (IPC)G01N33/53 +2 more

Timeline

Timeline From CIPO dates

1995199719992001200320052007200920112013Application filedFeb 1, 1994Patent grantedJan 15, 2002Term endedFeb 1, 2014

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.