1st August
Freeze slicing of about 50μm. Observe under natural light
microscope and can see red florescence. The thickness is about 130μm
4th August
Repeat the last experiment with silicone tube. 6rpm/s results in
a flowing speed of 68ml/day
6th August
Similar to the last time. Did not use freeze slicing.
15th August
Cultured E.coli in 5ml LB for 12h.
16th August
Substituting a part of silicone tube with glass tube in silicone
tube biofilm formation sets. Culture in 37℃
17th August
Add 50ml LB and culture with circular culture.
18th August
12.00 found one free-flow pump stopped. Cooled for 15 minutes and
turned on again. Could be over heated. Can see some bacteria on the
bottom of the vessel and tube. When the pump started again, the bacteria
was washed away.
19th August
Can observe obvious white biofilm where the silicone tube joins
the tube but cannot see red florescence, suspect contamination. No
biofilm is observed on the glass tube under microscope.
21st, August
Biofilm formation with large test tubes. Inoculate with 1%
e.coli. Rubber tubes are attached to air pump with filter between air
pump and the tube to prevent entrance of germs. Two sets use MSM
+glucose medium and two sets use LB.
Retry with glass tube biofilm formation set.
24th, August
Terminate biofilm formation, the glass slide left in the drawer
to dry. Can see obvious rod like structure under 400 magnification.
(spheres in MSM+glucose culture) No red florescence is seen. Most of the
surface is covered by single layer cells but some part of it has thick
bump like structure.
No biofilm observed on the glass tube.