OQ (Operational Qualification) for Electropolish - Orthopedic Cutting Tools

[Loren_apex]

My company is a orthopedics cutting tool manufacturer. Now we are required by one of customer to do process validation on electropolish and other special process. For OQ protocol of electropolish, does anybody have any suggestion on what should be the output of electropolish. My question is what we need to test to evaluate the performance of electropolish. My customer requires me to test cytotoxicity to make sure there is any acid residual after electropolish, but I don't think it is necessary.

 

[somashekar]

Re: OQ for electropolish

Welcome here ...
I am not talking about electropolishing, as this is a seperate process for surface polishing or passivating, that required a process validation.
However if your customer needs a "No acid residue" on the electropolished surface, you need to establish a protocol that ensures that the cleaning process after electropolishing meets this requirement consistantly.

If your requirement is polishing, then a measure of the surface roughness is an output indicator. If it is passivation, then an accelerated chamber test for corrosion resistance would do.
Same time considering customer requirement of "No acid residue" the cleaning process after passivation could be devised and merged within the electro polishing validation process.
Cytotoxicity is a biocompatibility test per specific standards which your processess will be able to meet and perhaps this is more the domine of your customer who has to get his products tested and determine that you freeze your electro plating operation per the protocol that made the biocompatibility test a pass.

 

[Loren_apex]

Re: OQ for electropolish

Somasnekar, thank you. Our process flow is electropolish--laser marking--passivation--final cleaning. we are validating electropolish, passivation and final cleaning separately. Corrosion resistance will be tested in passivation and cytotoxicity will be tested in final cleaning.
The electropolish I mentioned here is polishing, so roughness should be one output, but we have to ensure there is no acid residual which may damage the part after electropolish. I have no idea what should be tested to verify acid residual. My customer suggest cytotoxicity, but I think it is not reasonable.

 

[somashekar]

Re: OQ for electropolish

Somasnekar, thank you. Our process flow is electropolish--laser marking--passivation--final cleaning. we are validating electropolish, passivation and final cleaning separately. Corrosion resistance will be tested in passivation and cytotoxicity will be tested in final cleaning.
The electropolish I mentioned here is polishing, so roughness should be one output, but we have to ensure there is no acid residual which may damage the part after electropolish. I have no idea what should be tested to verify acid residual. My customer suggest cytotoxicity, but I think it is not reasonable.

cytotoxicity will be tested in final cleaning.

I am not clear how you would be doing this .. ? It is an elaborate testing process which also includes animal specimen.

I have no idea what should be tested to verify acid residual.

If your final cleaning process cycle has a base wash cycle and then demineral water rinse (you mention that you are validating electropolish, passivation and final cleaning separately) then I guess a pH test of the final cleaning media that is drained out should give you a proof that there is no acid residue if you always end up with a neutral pH result.