Appeal No. 1999-2141
Application No. 08/657,164
saline buffer to the venom before centrifuging to obtain a supernatant to apply to HPLC
column and fractionating by choosing a buffer within the pH of 7, to be within the skill of the
art”. Answer, page 5. The examiner suggests that at the time of the invention it was well
known that HPLC affords a convenient, high resolution method of separation by means of
a single step.
We do not find the examiner has established a prima facie case of obviousness on
the evidence of record. The examiner fails to provide evidence of record describing a step
of “diluting the taipan snake venom with phophate buffer saline”, as claimed. The examiner
merely concludes the step of adding a saline buffer to the venom before centrifuging to
obtain a supernatant to apply to HPLC column and fractionating by choosing a buffer within
the pH of 7, to be within the skill of the art. Answer, page 5.
What is further missing from the examiner’s analysis is why one of ordinary skill in
the art would have been motivated to combine or substitute a single pass reverse phase
HPLC method as described by Tyler and Bougis (a method based on a hydrophobic
separation parameter), with or in place of an ion exchange HPLC method as described by
Lind and Fohlman (a method based on a net molecular charge separation parameter) to
arrive at the method of preparing $-taipoxin, as claimed. See, for example Hearn, Table
3. Other than the ability of reverse phase HPLC to isolate specific venom components in
a single pass, Tyler and Bougis have little indicated relevance to the isolation of $-taipoxin
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