OMB Meeting Book_9-11-14

method’s applicability as written?

Study Director Response

clean up is well a lab for routine ould be use.

Study Directors are willing to work with laboratory to determine why no inositol peaks were detected.

’s necessary to use tuations will be for the HPLC column

A statement can be added to the method to allow for a helium sparge option. The comment "Area where temperature fluctuations will be minimal throughout the run" is to minimize changes in detector response due to air temperature fluctuations, but there is not a laboratory air temperature requirement. Maybe it would be more appropriate to change this comment to "maintain the electrochemical detector cell at a constant temperature throughout the run".

be very long (the rge?)

In Study Director's experience, these storage conditions are acceptable.

During the MLT, study directors discovered that there were significant differences between the ovens used by study participants. Even though all oven temperature were set at 110°C, samples did not appear to be exposed to the same amount of heat based on improvements in recoveries when oven temperatures were increased. Some participants with very low phosphatidylinositol recoveries were asked to increase oven temperatures to improve hydrolysis of phosphatidylinositol. If this method is approved as a final action method, hydrolysis conditions will need to adjusted. Study directors corrected an error in the method document after the original MLT study protocol was issued.

See Question 1, Comment 6, Study Director Response.

he data for the he free myo-inositol

ile using or regarding use of the method?

Study Director Response

d in a fume hood. 2) olution, or use more

A reference to perform sample cleanup in a fume hood can be added to the method. A very important step in the hydrolysis procedure that was in AOAC First Action 2011.18 Journal manuscript (J AOAC Int., Vol 95, No.4, 2012) was accidently omitted from the MLT protocol and the online 2011.18 method document. After samples are removed from the oven ~ 10 mL of water should be added to samples before adding NaOH.