Methylene blue?

This is similar to endoscopic tattooing, in which the indocyanine green and India ink have been found most useful. Sterile, ready to use India ink suspensions of pharmaceutical grade are available for this purpose.

Dear Vikas, "subcutaneous" layer of caecum...are you sure?

As to my anatomical and histological knowledge it might perhaps be "submucous"  but I've never heard or read about caecum as skin adnex, did you?

Best regards, Wolfgang

The question is correct in the title where it refers to submucosal layer of caecum. Adding to my previous answer: endoscopic tattooing is a technique used to mark colonic lesions by submucosal injections of appropriate dyes, such as India ink.

Apologies, Vikas!

Roman is correct, I am sorry that I only saw  "For my pilot experiment i need to give an injection with vehicle in the subcutaneous layer of caecum. "

As to the practical aspect of the question: in principle a lot of dyes (especially food dyes) are perhaps suited (if they stay long enough with the local area the vehicle was injected and don't interfere with the vehicle), yes, as Joe mentioned, as intravital stain methylenblue perhaps also is an option (e.g. S Thevarajah et al, 2005: A comparison of the adverse reactions associated with isosulfan blue versus methylene blue dye in sentinel lymph node biopsy for breast cancer @http://www.sciencedirect.com/science/article/pii/S0002961004005252

or Varghese et al, 2008: Methylene Blue Dye—A Safe and Effective Alternative for Sentinel Lymph Node Localization (http://onlinelibrary.wiley.com/doi/10.1111/j.1524-4741.2007.00519.x/abstract)

I guess you need the "stain" to "re"-identify the injection site as after a certain time when youprepare the site for further tissue processing (e.g.  into paraffin).

Best of luck, Wolfgang

Dear Wolfgang, if he plans to use a dye to mark the injection site, India ink or indocyanine green (ICG) would be more desirable options than methylene blue, indigo carmine, toluidine blue, or isosulfan blue, due to color stability in the injection site. Methylene blue and several other dyes (except for India ink and ICG) were shown to discolor in the injection sites within 24 hours, while India ink and ICG remain visible after 48 hours. India ink was also approved by the FDA for that purpose.

http://www.accessdata.fda.gov/cdrh_docs/pdf4/K042901.pdf

On the other hand, isosulfan blue or methylene blue are used for sentinel lymph node mapping, which poses somewhat different requirements on the dyes: they should not stay on the injection site, but should enter lymphatic vessels and flow to the sentinel lymph node/s so that they can be identified upon staining. 

Hammond DC, Lane FR, Welk RA, Madura MJ, Borreson DK, Passinault WJ.

Endoscopic tattooing of the colon. An experimental study. PMID: 2472762.

Roman, you again are right. I thought Vikas wouldn't mind to get an idea about some possibilities of intravital staining. Unfortunately I have no practical experience with setting marks with india ink and/or ICG...So I am thankful for the references you provided with your post. Best regards, Wolfgang

Dear Scientists,

Thanks for all your valuable comments and answers. I am sure your advice will help in my experiments.

Best

Vikas

I've just remebered that for Salpingoscopy, they used an anti-tuberculosis antibiotic, having an intense Orange color, Rifamycin. Is this useful in this experiences?

Regards, + salut