Bio-Rad xMark™ Microplate Absorbance Spectrophotometer - Manual (Page 9)

xMark Microplate Spectrophotometer User Manual
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1. General Information
1.1 Introduction
The xMark™, Microplate Spectrophotometer provides all the flexibility required for absorbance
assay. The xMark has the capability to perform standard colormetric ELISA and kinetic readings for
general cell screening with 6, 12, 24, 96, 384, and 1536-well microplate formats. The xMark uses a
“filter-less” design, with a wavelength range of 200–1000 nm. xMark is also provided with an
optional incubation feature with a temperature range up to 45°C. The optical design provides
verifiable results up to 4.0 OD. The “filter-less” monochromator design allows the user to set the
reading at any wavelength in the 200– 1000 nm region, as well as to perform a spectral scan within
200 – 1000 nm to find the absorbance curve.
1.2 xMark Specifications
Light source Xenon Flash Lamp
Photo detectors Two silicon photodiodes for measurement and reference
Indication range 0–4.000 OD
Resolution 0.001 OD
Spectral range 200–1000 nm
Monochromator capacity Any wavelength within the spectral range, with 1 nm step size
Monochromator bandwidth 5 nm FWHM (typical)
Wavelength accuracy ± 2.0 nm
Wavelength repeatability ± 0.2 nm
Optical photometric methods Single or dual wavelength
Compatible plates
6- to 1,536-well microplate with dimensions 128 mm (length) x 86 mm
(width) Plate height cannot exceed 21 mm
Accuracy
± 1.0 % or 0.015 OD from 0–3.0 OD at 490 nm single wavelength
reading
Linearity
96-well plate: ≤ 2.0 %, 0 to 3.000 OD at 405 nm
384-well plate: ≤ 2.5 %, 0 to 3.000 OD at 405 nm
1536-well plate: ≤ 2.0 %, 0 to 2.000 OD at 405 nm
Reproducibility
96-well plate: ≤ 1.0 % or 0.005 OD from 0 to 3.000 OD at 405 nm
384-well plate: ≤ 1.5 % or 0.010 OD from 0 to 3.000 OD at 405 nm
1536-well plate: ≤ 2.0 % or 0.015 OD from 0 to 2.000 OD at 405 nm
Uniformity
96-well plate: ≤ 2.0 % or 0.005 OD, from 0 to 3.000 OD at 405 nm
384-well plate: ≤ 2.5 % or 0.010 OD, from 0 to 3.000 OD at 405 nm
1536-well plate: ≤ 3.0 % or 0.015 OD, from 0 to 2.000 OD at 405 nm