Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!kitty!larry From: larry@kitty.UUCP (Larry Lippman) Newsgroups: sci.bio,sci.physics Subject: Re: Enzyme action Message-ID: <2123@kitty.UUCP> Date: Sat, 17-Oct-87 19:05:48 EDT Article-I.D.: kitty.2123 Posted: Sat Oct 17 19:05:48 1987 Date-Received: Sun, 18-Oct-87 12:05:34 EDT References: <240@ddsw1.UUCP> <2084@kitty.UUCP> <249@ddsw1.UUCP> <2100@kitty.UUCP> <255@ddsw1.UUCP> Organization: Recognition Research Corp., Clarence, NY Lines: 69 Keywords: More info... Summary: "No soap" for use of enzymes... [couldn't help the pun :-) ] Xref: mnetor sci.bio:763 sci.physics:2517 [A discussion about the desire of finding an enzyme to dissolve pine rosin used as a soldering flux in electronic circuit assembly; objections were raised as to the efficacy of existing solvent cleaning processes due to the inability to adequate penetrate the contact areas around SMD (Surface Mount Devices)]. In article <255@ddsw1.UUCP>, dino@ddsw1.UUCP (Laura Watson) writes: > ... > Because I want to invent a better solution than the best of the existing > ones available; they are just not quite good enough. As Hofstadter > would put it, I want to "jump out of the loop." > ... > Rosin is unique because it is acid only at > soldering temperatures. At room temperatures the abietic, pimaric, & etc. > acid molecules actually change to a non-acidic configuration. At room temperature, the major constituent of rosin is d-pimaric acid, which upon heating undergoes a methyl migration and forms abietic acid. Further heating and chemical reaction of abietic acid with the solder and other flux components converts it to a relatively inactive meso triacid. > But all of this application-specific reasoning notwithstanding, I think the > idea of enzymatic or other biotechnological cleaning agents would probably > be worthwhile even on regular industrial cleaning of various sorts. At cursory glance, the use of an enzyme to facilitate dissolving rosin sounds like a good idea, but upon further reflection, I do not believe it feasible. First of all, an enzyme merely functions to catalize another reaction; an enzyme performs no action per se in this application. What reaction can we catalyze? Saponification is the first which comes to mind, but even if such an enzyme existed, it would have difficulty in "surviving" at the high pH necessary for saponification. Abietic acid, d-pimaric acid and other constituents of rosin are terpenes (diterpenes to be precise), and I don't know what to do with them other than dissolve 'em in a solvent or saponify 'em. I don't see how an enzyme can facilitate either of those two processes. What you might be thinking of are "enzyme detergents" which have been touted in various advertising campaigns. But the enzymes in these detergents are generally bacterial proteases which hydrolize proteins. While hydrolyzing proteins may help remove some fabric stains of organic origin, they won't touch diterpenes. So I don't know what to tell you other than I do not believe that enzymes will help in this area. > Wouldn't it be neat if I could get a tankful of those microorganisms that > eat oil spills on the ocean cheaply enough to remove industrial oils from > metal parts? Wouldn't it be biodegradable? Couldn't I wash it down the > drain? Wouldn't it be less dangerous to people's health? Now, a genetically-engineered bacteria may be the solution, but I suspect that such a bacteria - if possible to create - would only serve to complicate a circuit board cleaning process. And then the rate of reaction would be quite slow. I know very little about genetically-engineered bacteria, so perhaps someone else could comment in more depth on this possibility. > Now that I have writ much more than I intended to on this subject, I > guess I'll get back to my favorite salt mine. It certainly never hurts to ask questions, and pursue new horizons even though alleged experts say it can't be done. I have done the same thing myself, often finding success. Unfortunately, here *I* am the one saying it can't be done... <> Larry Lippman @ Recognition Research Corp., Clarence, New York <> UUCP: {allegra|ames|boulder|decvax|rutgers|watmath}!sunybcs!kitty!larry <> VOICE: 716/688-1231 {hplabs|ihnp4|mtune|seismo|utzoo}!/ <> FAX: 716/741-9635 {G1,G2,G3 modes} "Have you hugged your cat today?"