[limpet chicken]

I just attempted to prepare a platinate sodium salt, by trying to dissolve fine platinum metal in hot saturated aqeuous NaOH, (NaOH+Pt->NaOPt+H?)

Unfortunately, the NaOH doesn't seem to have attacked the platinum, I intend to use it to electroplate a carbon electrode for use with some kolbe-based electrochemical experiments with alanine and tyrosine, but as yet, the NaOH has failed to attack the platinum metal.

Any ideas as to how to get the reaction to proceed? as I can NOT afford to buy shitloads of platinum, I thought about perhaps adding a tiny amount of mercuric iodide, as is done with Al/Hg reductive aminations, or even if nescessary, fishing the Pt out the petri dish I am using to hold it and the NaOH, cleaning the Pt with water, and preparing its iodide via sublimation of iodine under the metal.

Any better ideas?

[shelanachium]

Platinum is a noble metal which it is difficult to react with anything, and its oxide does not even form when it is heated in air, let alone with NaOH solution which attacks only active elements like Al and P.

Pt will however react (slowly) with aqua regia (conc. HNO3/HCl) to give a solution of the acid H2PtCl6. This can be used to prepare salts such as Na2PtCl6. If this is treated with NaOH solution you will get PtO2 and eventually sodium platinate Na2Pt(OH)6.

If you wish to use a platinum-containing solution for electroplating sodium platinate is probably not the best substance to use, perhaps a chloroplatinate as mentioned above or a platinocyanide such as K2Pt(CN)4 made by reacting a cyanide with a chloroplatinate. Might be best to look up 'platinum electroplating' on the web, but in any case to get the platinum into solution in the first place, make a chloroplatinate using aqua regia. Good luck!

[Borek]

Platinum is a noble metal which it is difficult to react (...) with NaOH solution which attacks only active elements like Al and P.

Not exactly. Melted NaOH attacks platinum, thus it will be not strange if concentrated and hot solution will corrode it too.