Page:NIOSH Manual of Analytical Methods - 5044.pdf/6

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EST RO GE NIC C OM PO UN DS: M ETH OD 5044, Issue 1, dated 1 5 Ma rch 2003 - Page 6 of 6 APPENDIX 1: PREPARATION OF SPIKES ON W IPES: W ipe m edia (W ash 'n DriĀ® Moist Dispos able Tow elettes) were opened and spread to evaporate to dryness. Dried towe lettes w ere rolled and ins erted into 16 x10 0-m m PT FE -lined s crew ca p tubes. A Ham ilton syringe was used to place measured am ounts of stock solution in methanol (50 :L containing 40 :g of each analyte) on each wipe. After allowing the spikes to evaporate, 8 mL of m ethanol was added to each tube, and the tubes were capped and rotated overnight at room temperature to extract the spiked analyte from the wipes.

EFFICIENCY OF EXTRACTION: Com pound

Efficiency of Extraction (%) (n=6)

Sr

$-Estradiol

100

1.4

Estrone

97

3.1

Progesterone

99

0.82

$-Es tradiol 3-Be nzoa te

99

0.76

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition