Silk Road forums

Discussion => Drug safety => Topic started by: Tryptamine on May 30, 2012, 05:53 pm

Title: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: Tryptamine on May 30, 2012, 05:53 pm
http://beesafe.goshopper.net/i/18284/marquis-reagent-1milliliter.htm

Found this very cheap source of these two reagents, figured the benefit to SR outweigh the -1s I may receive from vendors who sell single use tests.
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: winterjacket1 on May 30, 2012, 07:45 pm
that is a good deal. have you ordered from them before? where do they ship from?
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: Tryptamine on May 30, 2012, 08:31 pm
Haven't ordered, saw it posted on some chemistry forum about making marquis reagent. Considering what these reagents actually are these prices are extremely high; marquis reagent is sulfuric acid mixed with formaldehyde, which costs next to nothing to make if you can find a source for formaldehyde. Still, it's orders of magnitude cheaper than buying a 'test kit'.
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: ozzybattla on May 30, 2012, 11:59 pm
http://beesafe.goshopper.net/i/18284/marquis-reagent-1milliliter.htm

Found this very cheap source of these two reagents, figured the benefit to SR outweigh the -1s I may receive from vendors who sell single use tests.
I'm in Australia. Anyone know if these are allowed to be sent in the mail internationally? Wouldn't want to get in trouble for illegaly sending stuff in the mail. :-)
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: krigger on June 29, 2012, 02:24 am
http://beesafe.goshopper.net/i/18284/marquis-reagent-1milliliter.htm

Found this very cheap source of these two reagents, figured the benefit to SR outweigh the -1s I may receive from vendors who sell single use tests.

Great thanks! I was just about to order the dancesafe.org kit, which seems too expensive for what it is.
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: MasterS on June 29, 2012, 03:43 am
I think the ratio is 10 sulfuric acid : 1 formaldehyde. When I last looked the smallest amount I could find for them came out to the same price as a kit but you'd get 2 liters of the stuff and it does have a shelf life. so unless you plan on selling excess it isn't worth it.
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: weedsaves on June 29, 2012, 08:05 pm
I think the ratio is 10 sulfuric acid : 1 formaldehyde. When I last looked the smallest amount I could find for them came out to the same price as a kit but you'd get 2 liters of the stuff and it does have a shelf life. so unless you plan on selling excess it isn't worth it.
Would be a cool thing to supply friends with at festivals. Any idea how long the shelf life is?
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: MasterS on June 29, 2012, 08:13 pm
From what I remember like 6 months buy I'm sure there are a lot of variables to affect that
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: bogben on June 29, 2012, 09:13 pm
the marquis mixture may have a limited shelf life but sulphuric acid and formaldehyde dont! (well of course they do but its huger and its an inexact enough test that they hardly need to be analytical grade and freshly made to be of use.) just mix up 50ml batches as needed, much cheaper I'd have thought.
Title: Re: Dirt Cheap Reagent Tests! (Marquis & Erlich)
Post by: Ben on June 30, 2012, 12:28 am
Considering formaldehyde is a gas, preparing the reagent is not the easiest thing to do outside of lab conditions. To prepare the reagent on the spot its probably most practical to keep a (nearly saturated) solution of formaldehyde in methanol in stock, and mix that carefully with sulfuric acid just prior to performing the test.

Having some methanol in the marquis reagent isn't a bad thing since it will slow down reaction rate, allowing you to observe any color changes better.