Make sure you have good contacts for the pipette and reference electrodes, and no salts/flooding around the bath.

Try resetting capacitance & Rs prediction-compensation if you haven't already. I remember sometimes switching modes (IC/VC) and resetting everything helped (offsets, capacitances etc).

Finally, try removing and replacing the grounding wires! Sometimes ground loops cause more noise than no ground at all.

Thank you so much for your reply...I am sure contacts between the pipette and bath electrode no salts flooding around the bath.. I have done the restoring option in multiclamp but it dint work.. I think the problem with the grounding connections.. I will check that...

Thank you so much..

You do not mention any about the reference electrode connection. -What about that?

Hy Anantha,

The connections that you have made between the Multiclamp 700B and the DigiData 1550 are ok.

Are both the table and the Faraday's cage connected to the amplifier’s ground? All the grounds should be connected to the amplifier’s ground, the distribution bus as well, so if you did it you should not have electrical noise.

I am sorry for the question ¿Have you put into the bath solution both the pipette and the reference electrode?

It seems your problem is that the reference electrode and electrode wires are not chorided enough.

Please visit https://www.scientifica.uk.com/neurowire/labhacks-tips-for-improving-your-electrophysiology-experiments where you will find tips for Patch Clamp recordings, including troubleshooting of electrical noise in the recordings.

Dear Luis and Enrique,

Thank you so much for your reply.

Yes I connected reference electrode and patch electrode to the bath solution and the other end of the reference electrode connected to the head stage gold pin.

Yes the table (there we kept our amplifier, digidata etc) connected to the distribution bus. And I connected a wire from the distribution bus to the signal ground which is in the back side of the amplifier.

I have not grounded the faraday cage to this distribution bus, I will connect that. I will chlorinate again the bath and reference electrode.

Thank you once again for your suggestions.

Dear all,

Thank you very much for your reply

I chlorinated the silver wire and bath electrode for some 15 minutes in clorox solution and I have done the cleaning process also. It seems the noise level reduced from 480 pA to 100 to200 pA however the OVLD button in the amplifier is getting on for some time when the pipette in the bath solution (some time it is off).

The second problem am facing it when am adjusting the pipette offset to 65/73 mV only, I can see the square pulse that too with a big transient and the resistance value in the multiclamp commander is greatly varied from mega ohm to giga ohm, what could be the reason

I would appreciate your suggestions for this also.

Thank you

Dear Anantha,

You told us that: “the table (there we kept our amplifier, digidata etc) connected to the distribution bus…...” You should keep the amplifier and the digidata out of the table and of the Faraday’s cage. And connect all the ground wires to the distribution bus and this to the signal ground which is in the back side of the amplifier. You take into account that the microscope could be a source of electrical noise as well, try to connect it to the distribution bus.

Do not forget to visit https://www.scientifica.uk.com/neurowire/labhacks-tips-for-improving-your-electrophysiology-experiments where you will find tips for Patch Clamp recordings, including troubleshooting of electrical noise in the recordings.

Best wishes

Dear Luis,

Thank you so much for your reply. I will look into that site. Yes we have kept amplifier, digidata and micromanipulator controller in the other table and I have connected that table to the distribution bus. Yes microscope also I grounded to that ground distribution bus.

I am chlorinating almost everyday the reference electrode and the bath electrode before starting the experiment. The overload button is sometime on while entering into the bath solution. When I am doing the pipette offset after entering into the bath solution, the overload button is getting off.

Thank you so much for your suggestions.

Do you reset to program defaults icon in the multiclamp program each time you finish an experiment or change electrodes?

Thank you Luis.

Yes am doing that when ever I am starting with the new pipette.

hi Anantha.. hope you resolved your issue. indeed we use the same Multiclamp 700B, Digidate 1550B, our pclamp dongle is missing can u assist me?