BSA coating on pncSi (2D)
I coated the pncSi samples from W683 (no RTP) with Bovine Serum Albumin (BSA) in Tris-EDTA buffer. Three different concentrations were used: 1 mg/ml, 5 mg/ml and 10 mg/ml (usual range of BSA conc. used for coating Si surfaces). The samples were left in BSA solution for 45-60 mins at room temperature and almost dried, after which they were incubated in DMEM (-FBS) @ 37C in Oven (in 2D & 3D format). Samples w/o coating were used as controls.
Discoloration was monitored over 3-4 hours and following images were captured. BSA coating should prevent the discoloration (higher the conc., more time should it take to discolor).
This experiment was carried out in order to check if functionalization of the membrane can help in preventing its degradation since the actual mechanism of discoloration could not be fully interpreted from all the recent studies.
As seen above, after 3 hours, the sample in DMEM(-FBS) with no coating discolors to a much greater extent in comparison to the sample with high conc. BSA coat (10mg/ml i.e. 1% BSA). Also, the gradual difference in color can be seen with the change in BSA conc. BSA does slow down the degradation mechanism of the pncSi.
It will be interesting to see how long does the BSA coated sample last in Sepcon format.
A clean result. Now silanization and carbonization please.
I will use the silanization protocol previously used and see how it goes. Regarding carbonization, will do some basic study and coordinate with Dave.
What is the “water” sample? Was it placed in the oven for the same period of time? Is there any BSA on it?
Also, wouldn’t each of these surface treatments have a different starting color? It seems like an image at time 0 would be needed to definitively judge this effect.
The discoloration seems quite uniform.
“Water” sample is the chip in water with no BSA, in oven for same period of time. I don’t think there is much difference in the starting color in surface treated samples. But I will make sure to take zero time point pictures.