Biotek Epoch - Stock Solution Formulation

34 | Chapter 4: Instrument Qualification
Stock Solution Formulation
The stock solution for Liquid Tests 1 and 2 may be formulated from the chemicals
listed below, or by diluting a dye solution available from BioTek. See Procedure A
or Procedure B outlined below and on the following page for details.
Procedure A
Required Materials:
• BioTek QC Check Solution No. 1 (PN 7120779, 25 mL; or 7120782,
125 mL)
• Deionized water
• 5-mL Class A volumetric pipette
• 100-mL volumetric flask
Preparation of Stock Solution:
1.
Pipette a 5-mL aliquot of BioTek QC Check Solution No. 1 into a 100-mL
volumetric flask.
2. Add 95 mL of DI water; cap and shake well. The solution should measure
approximately 2.000 OD when using 200 µL in a flat-bottom microwell.
This should create a solution with an absorbance of about 2.000 OD when
using 200 µL in a flat-bottom microwell. The OD value will be proportional
to the volume in the well and the amount of QC Check Solution No. 1 used.
You can use a larger or smaller well volume, or add more Check Solution or
water to adjust the stock solution.
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Too small a well volume may result in increased pipetting-related
errors.
Procedure B
Required Materials:
• Deionized water
• FD&C Yellow No. 5 dye powder (typically 90% pure)
• Tween 20 (polyoxyethylene (20) sorbitan monolaurate) or
BioTek wetting
agent, PN 7773002
• Precision balance with readability of 0.001 g
• 1-liter volumetric flask
• Weigh boat
BioTek
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Instruments, Inc.