I don't know of organometallic compounds, but this study designed a specific detector:  http://search.proquest.com/openview/ec7fef7110dc6ef28a4c1a24864cfc56/1?pq-origsite=gscholar

Thank you so much sir.

This is a site on Creatinine colorimetric detection kit

Low price, rapid creatinine detection kit for diabetes, cardiovascular and renal research.

https://www.google.com.eg/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&uact=8&ved=0ahUKEwid49Oh_8fOAhUDOhoKHStQDikQFgg9MAM&url=http%3A%2F%2Fwww.enzolifesciences.com%2FADI-907-030A%2Fcreatinine-colorimetric-detection-kit%2F&usg=AFQjCNHDnZ44GbbUd109W_XhWYZ1L-1XSA&bvm=bv.129759880,d.d2s

Thank you so much sir. But the composition of the detection reagent has not been indicated.

I have not gone through the cited references, may be they have given better answers to your question. However i will answer your question around the logic that creatinine (2-Amino-1-methyl-5H-imidazol-4-one)  in its stable tautomeric form has an amine group attached to 5 membered ring which is an excellent ligand to most transition metals especially copper(II) and cobalt(III). so a copper(II) fragment can selectively bind to the creatinine with a significant thermochemistry. Some literature references for copper complexes of creatinine are as under:

DOI: 10.1016/S0277-5387(00)83797-3

http://dx.doi.org/10.1080/00958979009408216

http://dx.doi.org/10.1081/SIM-120030438

In fact the Quantification of creatinine in biological samples is also based on the pseudoenzyme activity of copper–creatinine complex see the ref.http://dx.doi.org/10.1016/j.saa.2012.02.104

The Fluorescent creatinine assay is a method of detecting creatinine in body fluids using an indicator which produces a fluorescent response when oxidized in the presence of a copperII/creatinine complex. A preferred indicator is 4-(1-methylhydrazino)-7-nitro benzooxadiazole (MNBDH) see ref.(US 6872573 B2)

Fundamentals of Urine and Body Fluid Analysis

https://books.google.co.in/books?isbn=0323277748

Nancy A. Brunzel - 2013.

In summary a copper(II) based fragment either from the above cited references or a newly designed one can do the job one such designed complex in described in the reference DOI: 10.1016/j.saa.2015.10.028 .

Good luck

Thank you so much sir. I agree that copper binds to creatinine but copper also reactively binds to many biomolecules in the blood, especially albumin. Thus it cannot be used selectively for creatinine detection.

Dear Pallavi Dasgupt,

Creatinine colorimetric detection kitR is find in attach.

Dear Pallavi Dasgupta ,

Yes, unfortunately the composition of the detection reagent has not been indicated.

Yes sir but I am guessing it will be based on immunoaffinity, attributing to its selectivity.

I think so