I am doing a literature review about the detection methods of amylase in saliva and have been reading through journal articles mainly from the 1970s about such methods. One particular method involved a reagent called "Procion Red MX2B-amylopectin". From papers i have been reading it appears as though this method was discontinued although i cannot find a reason as to why. I was wondering if you have any information on "Procion Red MX2B-amylopectin", and if you can tell me is it still in production, or if not, the reasons why it was no longer manufactured.

When I was in graduate school, in the nineteen-eighties, reagents such as this were not necessarily manufactured. The researcher often had to prepare the reagent for him or herself, following instructions that had to be obtained from the author of the paper that reported the use of the assay.

My guess would be that the assay may have fallen by the wayside if an easier assay became available, or even commercially available. Or, it may be a perfectly good assay, and you just need to determine, by contacting the authors of the relevant papers, exactly how to prepare this reagent for yourself. Presumably, the preparation involves allowing the purified dye to react with the amylopectin under carefully controlled conditions. Dichlorotriazine dyes will react with both carbohydrates and proteins, given the right pH and temperatures.

There are many different dichlorotriazine dyes, which are what the Procion MX name refers to. It is the name under which the dyes were patented, though the patent has long since expired. I do not know of a commercial source for small quantities of Procion red MX-2B, which bears the Colour Index name of reactive red #1, and the Colour Index number of 18158, but it is apparently still being manufactured; do a web search for "reactive red 1". It is listed among dyes being sold, in larger quantities, by Classic Dyestuffs. It seems likely that many other dichlorotriazine dyes would be equally well suited to the procedure.

You may benefit from reading a book edited by Victor B. Ivanov, entitled Reactive Dyes in Biology. (ISBN 3-7186-0235-0. Originally published 1982; English translation 1987. Harwood Academic Publishers, PO Box 786, Cooper Station, New York, NY 10276.) This book is too expensive for most students to purchase, but my institution's medical library has a copy; perhaps you can find a copy at a medical library near you.