Dissolving Melatonin

Tom McCloud McCloud at dtpax2.ncifcrf.gov
Wed Dec 4 08:33:22 EST 1996

Mutant wrote:
> For my science experiment this year I am going to inject melatonin into potato tumors...what can I use to dissolve it?  

Your experiment has similarities to the 'Crown Gall Tumor bioassay' as
championed by McLaughlin.  Read Methods in Plant Biochemistry vol6 p1
1991.  In his assay compounds being tested are dissolved in DMSO, which
is subsequently diluted with 3 volumes of water.  This is put onto the
potato discs at the same time as the Agrobacteria, prior to development
of the tumors.  Do you really intend to inject *INTO* the tumor???  Have
you done appropriate controls, for example injecting water into these
tumors and seeing if there is any effect?  Have you injected DMSO/water
solutions with increasing amounts of DMSO present to see if there is an
effect?  What is the limit of DMSO that cam be present before cell death
    Melatonin is a moderately polar substance and DMSO is a good choice
for dissolving it.  Other organic solvents in which melatonin would be
soluble would have deleterious effects on living cells too. You could
try ethanol or ethyl acetate.  If you must put it into an essentially
aqueous solution then perhaps adding a detergent like tween 80 may
help.  And you might determine whether a very slightly basic solution
like bicarbonate might improve solubility.   Tom McCloud

More information about the Microbio mailing list

Send comments to us at biosci-help [At] net.bio.net