12
Manual: Heating Insert P – Lab-Tek™ type
www.pecon.biz
12.01.2004
FoilCover for
POC-R Chamber ("open cultivation") and Petri dishes
Reduction of evaporation of water out of nutrition media, agar and methylcellulose.
Petri dishes used for cell and tissue culture are generally disposable dishes (polystyrene) with a cover
which rests loosely and slightly prone on the top of the dish. This guarantees the exchange of the gas
phase between ambient air and dish atmosphere.
The
disadvantage
of this construction is a relatively
high rate of evaporation
leading to a higher con-
centration of ions in the medium and thus damage to cultivated cells. Therefore, most of the
laboratory incubators have a relative humidity of more than 90% at 37°C.
Cells, which are cultivated in Petri dishes in incubators with a low relative humidity (e.g. microscope
incubators, Zeiss), should be better protected against evaporation of water.
The rate of evaporation in Petri dishes can be reduced by
a
special cover
. The cover has an optically clear
foil
(CultFoil)
, which is
permeable
for gasses like CO
2
, O
2
, N
2
;
in contrast, water molecules can pass this foil only at
higher temperature and pressure (i.e. during autoclaving).
The foil rests directly on the rim of the dish.
The FoilCover
can not be used with DIC !
The cover consists of:
base ring, foil and stretching ring
and can be assembled very easily. The
sterilization is carried out after assembly
in an autoclave (+121°C) or by dry heat at approx.
+165°C. If after use the foil in the cover is not cracked, it can be used again after sterilization.
Comparison of the rate of evaporation:
CO
2
-incubator versus microscope incubator.
Evaporation of water from "60" Petri dishes (5 ml Hank's buffer) in the incubation system of an inverted
microscope compared to Petri dishes in a conventional CO
2
-incubator:
gas exchange
Petri dish
Petri dish
with FoilCover
The measured values demonstrate the distinct advantage of the FoilCover, especially if cultivated
cells are investigated in Petri dishes or the POC-R Chamber ("open cultivation") under the
microscope.
There are different types of FoilCover
Description
Order No.
1 Cover for
POC-R Chamber ("open cultivation")
consisting of stretching ring and base ring
0727.025
1 package à 25 pcs CultFoil, 25 µm
0727.026
1 Cover for
35 mm
Petri dishes
consisting of stretching ring and base ring
0701.000
1 package à 25 pcs CultFoil, 25 µm
0701.001
1 Cover for
60 mm
Petri dishes
consisting of stretching ring and base ring
0702.000
1 package à 25 pcs CultFoil, 25 µm
0702.001
normal cover
FoilCover
relative humidity
of ambient air
microscope incubator
40µl/h
4 µl/h
20% at 37°C
CO
2
-incubator
3 µl/h
95% at 37°C
Incubation system on the inverse microscope:
CTI-Controller 3700, Tempcontrol 37-2, Incubator S, Heating Insert P
stretching ring (stainless steel)
CultFoil, gas permeable
(25 µm)
base ring (stainless steel)
A
ss
e
m
bl
y
