September 2016 SPDS Book

Recovery, Repeatability & Reproducibility

>20 - 1000 ppm

> 0.1% -

Range ≤ 5 ppm 5 - 20 ppm

1% > 1%

% Recovery

75 – 115 80 – 110 95 – 105 97 – 102 98 - 102

% RSD r

≤ 12

≤ 8

≤ 5

≤ 4

≤ 2

%RSD R

≤ 20

≤ 12

≤ 8

≤ 6

≤ 3

Reported as individual vitamin B 12

analogs

% Recovery, % RSDr and % RSD R

shall be determined individually for

each claimed matrix.

Comments Submitted

COMMENT: • Methylcobalamin is the least stable [form of B 12 ] and will convert to other forms in the presence of extraction solvents or matrix components many unknown An assessment should be done to , . demonstrate stability of extracts under extraction conditions, etc. This is critical to measurement of methylcobalamin. • Add stability of neat solutions to demonstrate lack of interconversion to other B 12 species. Alternatively, add more detail on matrix requirements for testing to include various types of tablets, capsules, etc. RESPONSE: Suggest adding this statement to the Validation Guidance section, “Because some vitamin B 12 forms are unstable, the stability of vitamin B 12 in extracts should be demonstrated during analysis."