Roche Cedex HiRes, Operator'S Manual

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Overview
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A Overview
The Cedex HiRes Analyzer automatically determines the cell concentration and viability of cell suspensions.
The analysis is based on the Trypan Blue Exclusion Method whereby cell suspensions are stained and analyzed.
The data obtained allows for the evaluation of the overall state of the cell culture, including the specifi c growth
rate and doubling time of a cell population, as well as the documentation of the cultivation process.
The evaluation of the samples is based on automatically obtained digital images that are analyzed using analysis
software on a separate computer (Cedex HiRes Control Unit). All the necessary steps – from the staining of
the samples to the recording and evaluation of the image data – are automatically performed by the analyzer.
Recognition and differentiation of cells as either viable or dead is done under standardized conditions, which
provides very precise and objective results.
A variety of parameters, including Viable Concentration, Total Concentration, Viability, Total Object Count,
Average Compactness and Average Diameter are analyzed using result data from single images, as well as from
all of the selected images of a sample. Standard deviation ( Std. Dev. ) of the number of cells from image to im-
age is also calculated. In addition, the Aggregate Rate , which shows the percentage of the total number of cells
that appear in aggregates (clusters), is determined for both single images and all of the images. The use of a Live
Operator makes it possible to directly observe the effects on the analysis of a sample when the image analysis
software ( Operator) is adjusted.
Graphical representations of the measurement results can be viewed in the Measurement Statistics Histogram,
Diameter Histogram, Compactness Histogram, Aggregate Histogram and Cultivation Time Chart . In the
Measurement Statistics histogram, individual images can be compared to give a better overview of the distri-
bution of the cells in the images. The Cell Diameter Histogram shows the diameter distribution of living cells.
The Object Diameter Histogram shows the diameter distribution of all objects detected such as cells, debris,
air bubbles and viable and dead cell aggregates. The deviation of the shape of living cells from that of an ideal
sphere is represented in the Compactness Histogram. The Aggregate Histogram provides an overview of the
amount and size of aggregation found in the cell culture.
The Cultivation Time Chart displays growth curves and cultivation parameters in a time- dependent manner.
The results of the Cultivation Time Chart can be separately printed out. For further processing of the results in
other programs, data export in formats such as Excel-compatible formats and CSV (Comma Separated Values,
generally applicable) is possible. The Cultivation Time Chart includes calculations for the doubling time [T]
and specifi c growth-rate [
µ
].
The Cedex HiRes Software 2.2 can be operated on Windows
®
XP Professional. Secure data handling, as well as a
carefully designed user management system, guarantee compatibility with 21 CFR, Part 11. Access security for
the Cedex HiRes System has been stepped up. Access is only allowed for authorized persons. The workstation
can be automatically blocked after a certain number of consecutive entries of a false password via the Systems
Options. A warning message will appear before the last allowed attempt.