Personal bioreactor RTS-1 & RTS-1C
Edition 3.-4.03
– July 2017
Operating instructions
Page 11
9. Temperature control
9.1.
Rotation intensity influence on temperature accuracy of the sample
Rotation intensity influences air transfer introduced to the tube from the outside environment.
Table 1. Temperature differences (
Δ t°C) between tube sample and set thermoblock temperature, depending on aerobe and
microaerophilic rotation intensities at ambient temperature 23 °C ± 2 °C and 45% ± 10% RH.
Set temperature on RTS
t
°С
Sample real temperature
t
°С at 250 RPM 10s RSF s
-
1
Sample real temperature
t
°С at 2000 RPM 1s RSF s
-
1
70
71
67
60
61
57
50
51
48
40
40
39
30
30
29
20
18
19
10
8
10
4
4
8
9.2.
Dew point temperature influence on measurement system accuracy
OD measurement accuracy is affected by moisture that can appear on the outside wall of the tube because of dew point temper-
ature. Relative humidity and temperature affect the dew point; therefore, the temperature of the tube must be higher than the dew
point temperature for the measurement system to work correctly.
Figure 7. Graph of dew point temperatures influenced by relative humidity.
9.2.1. Finding dew point temperature for the user.
-
Find the corresponding curve on fig. 7 that matches the humidity of the room in which the device is located.
-
The horizontal axis indicates the temperature of the room in which device is located.
-
Using that information, make a projection on the vertical axis. The found point on the graph is the temperature of the dew point.
9.2.2. Avoiding dew point temperature during temperature profiling
If the dew point temperature reached, moisture will disrupt correct measurement of the system.
To avoid dew point temperature, decrease the temperature difference between the ambient temperature and bioreactor and sam-
ple temperature. By placing the bioreactor to an environmental chamber, the temperature difference can be significantly lower.
Example of calculation of environmental chamber temperature selection:
If the range of temperature profiling is from +10° C to +40° C, calculate the environmental chamber temperature:
(40-10) / 2 = 15
°C
9.3.
Cold room and environmental chamber influence on temperature accuracy of the sample
It is possible to place the device in a cold room or environmental chamber, but the temperature of thermoblock and temperature
of the sample will not be accurate at specific temperature ranges. Temperature measurements of the sample and corrections at
maximum and minimum temperature ranges or 4°C-10°C and 60°C-70°C must be performed by the user. If any additional ques-
tions appear, please contact RTS support team directly for assistance.
9.4.
Change of optical characteristics of the tube depending on temperature
When temperature of the plastic material is changing, i.e. during temperature change of 3
0°C every hour, the plastic material of
the tube changes optical characteristics in a range of ±0.1 OD.
-20
-15
-10
-5
0
5
10
15
20
25
30
35
40
45
50
0
5
10
15
20
25
30
35
40
45
50
Dew
Po
in
t
T
e
m
p
e
ra
tu
re
[
°
C]
Temperature [
°
C]
95% humidity
90% humidity
80% humidity
70% humidity
60% humidity
50% humidity
20% humidity