Multichannel Systems MEA Manual User Manual

Page 38

MEA Manual

Nitrocellulose solution

 For preparing a stock solution, dissolve a piece of 1 cm

nitrocellulose membrane in 10 ml methanol.

Stock solutions may be stored at room temperature in polystyrene tubes. For the working solution, dilute
the stock solution 10 : 1 with methanol. You can adjust the concentration to meet your requirements.

Procedure

Directly before use, pipette 3 – 5 μl of the working solution onto the recording field. The recording field
should be completely covered.

Remove the coating solution and let the MEA air-dry. It takes just a few seconds for the methanol
to evaporate.

Literature

Ulrich Egert, Thomas Meyer (2004); Heart on a Chip — Extracellular multielectrode recordings from cardiac
myocytes in vitro, "Methods in Cardiovascular Research", S. Dhein and M. Delmar (eds.)

5.4.2 Coating with Polyethyleneimine (PEI) plus Laminin

Polyethyleneimine (PEI) has been successfully employed for dissociated cell cultures and proven to enhance
cell maturation in culture compared to polylysine coated plates. Polyethyleneimine is a positively charged
polymer and thus changes the charge on the glass surface from negative to positive. The tissue sticks even
better with this method than with the nitrocellulose method, but the polyethylenimine forms a uniform
layer that can get more easily detached from the surface, for example, by the perfusion. This coating
method can optionally be combined with laminin.

Materials

 Poly(ethyleneimine) solution (PEI)

(Sigma-Aldrich, Inc., P3143)

 Boric

acid,

crystalline

(Fisher

Scientific,

A73-500)

 Borax (sodium tetraborate)

(Sigma-Aldrich, Inc., B0127)

 1 N HCl

 Laminin,

1mg/ml (Sigma-Aldrich,

Inc.,

L2020)

Borate buffer

 3.10 g boric acid

 4.75

borax

 Dissolve in 1l distilled water at 80 °C.

 Adjust pH to 8.4 with 1 N HCl.