Biotek ELx808, Operator'S Manual

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| Chapter 4: Instrument Qualification
™
Do not remove the filters from the test plate, and do not
use alcohol or other cleaning agents to clean them.
¾ Check the microplate carrier to ensure that it is clear of debris.
•
Channel-to-Channel Variation
:
This test ensures that selected channels
read the same value for a filter as their paired channel when the plate is
“turned around” 180° in the plate carrier. It is a way to verify that each
channel’s Delta values are adjusted relative to the signal strength of the
reference channel.
Empty Carrier Test
The Empty Carrier Test confirms the ELx808’s read capabilities at the 100% light level,
and can help to identify deteriorating interference wavelength filters and other optical
problems.
Liquid Tests
Conducting Liquid Tests confirms the ELx808’s ability to perform to specification with
liquid samples. Liquid testing differs from testing with the Absorbance Test Plate in
that liquid in the wells has a meniscus, while the Test Plate’s neutral density filters do
not. The optics characteristics may differ in these two cases, alerting you to different
types of problems. The Absorbance Test Plate will indicate the absolute amount of light
absorbed, which will effectively test the linearity of the electronics. The liquid tests will
help detect optical defects such as dirt on the lenses or other contamination that can
contribute to errant readings.
•
Liquid Test 1 tests the alignment, accuracy, repeatability, and channel-to-
channel variability of the reader, making evident any problems with the
optics of the system. If you have the Absorbance Test Plate, you will only
need to run Liquid Test 1 for routine testing.
•
If you do not have the Absorbance Test Plate, test the linearity,
repeatability, and alignment of the reader by preparing a series of solutions
of varying absorbances as described in
Liquid Test 2 .
•
Liquid Test 3 is an optional test at 340 nm, offered for sites that must have
proof of linearity at wavelengths lower than those attainable with the
Absorbance Test Plate. This test is considered optional because the reader
has good “front end” linearity throughout its wavelength range.
BioTek Instruments, Inc.