questions about DIY magnet implants?



  • so you want to ghetto fab this because you dont want to wait a month or so and you cant afford a 50 dollar magnet?
  • That's kinda the angle I am looking from. Like I understand enjoying DIY, but when it comes to something that already exists, and can be had for cheap in a form that is exponentially better than anything you could cobble together... why?
  • edited December 2015
    re: tests: okay, guys, you got me there. I don't understand anything about that iodine thing. .... are you trying to dissolve nickel? ... and why? ... my magnets aren't gonna be nickel-coated, anyway (well, tbh, the plating is something like ni-cu-ni-au plus uv gel, and the test would be to see how long it takes for the gold to leave the underplating exposed.... as in, the uv coat is protecting the gold layer).

    bciuser: oh, I've considered that, too. problem is, I'm not sure I have the precision to do the procedure with my left hand (... since I'll be implanting the magnet myself). so my other options are, either on my left thumb, where I'd guess I'll have no problems with the violin, or the left ring finger, still on the fingertip but more towards the hand, since for violin, you really only put pressure in the very tip. I guess I have to think of it a bit more, since the right hand still seems like the way to go... but doing it will be quite difficult.

    @ThomasEgi: whoa, that IS a great idea. yes, a minor wound is nothing to worry about, it's not like I wasn't planning to have a scarification, anyway... I may do it. just for the science. :)

    @Cassox: of course, I'll do the research first, especially in regards to materials toxicity and resilience/stability. then, if it looks like those both are good to go, I'd do an actual test and implant it. probably in a leg or something as @ThomasEgi suggested.  .... so, yep, no way to have it before christmas, I guess... sigh. IDK. I'll keep thinking.

    @ightden and @trybalwolf: yep. kinda. but think this: what if I end up discovering something almost as safe as TiN, but much more affordable? huh? and what if, while not as safe, is enough for my own purposes? as I said, I highly doubt that any plating can last more than a few years. so, if TiN can last, say, 10 years, and gold plus UV gel lasts 5... I'll be happy. can't I be? :)
  • @Cassox - word. that's pretty clear. bummer.
  • about TiN coating. It's most commonly used coating for tools for metal processing. Read as, it's used to cut steel into tiny pieces at high speed. That's one hell of a durable ceramic. Gold, parylene, and the likes are super weak compared to TiN. Try cutting a massive block of steel into pieces using gold or UV-cured paint and you may get the idea in difference of mechanical durability.

    @niky45 the tests you want to run are specified in ISO 10993-1 Evaluation and testing. Cytotoxity, sensititazion, irritation/intracutaneous, acute systemic toxicity, subcronic toxicity, genotovcity, and after all those are ok, implantation. I recommend against skipping any of those. You don't want to poison yourself, neither get cancer (well at least i think you don't want to).
  • Also, titanium nitride (TiN) has already been tested and actually used for some rather extensive bone implants:
  • @ThomasEgi: yeah, and silicon carbide is also used for machining steel, and a weak bump could break any piece in two. (guess what? I've been machining some steel this weekend with silicon carbide tools).

    I.e. hardness is NOT a measure of stability against, say, friction, or contact with corrosive liquids (i.e.blood). and so, lack of hardness doesn't mean it will last less.

    as for the ISO tests, yeah, I've read about those. that's why I need the ingredients list, if none of the ingredients is toxic or carcinogen, then the material should be biologically safe. or am I missing something?

    anyway, the end result of the UV gel is an acrylic layer. as such, acrylic is widely used in body-jewelry. even though some say it can be a carcinogen, I gotta investigate it some more, since I don't see the EU allowing such a massive sale of something actually dangerous. also, as a fun fact: aluminum is also said to be carcinogen, and the most used titanium alloy has aluminum.... so everything's relative in the end.
  • post pictures once it rejects plz!
  •  :D

    You call blood a corrosive liquid. It's not.

    There is a correlation between objects having a higher youngs modulus and their durability. It's not the be all end all, but I wager my ceramic knife is going to be around a bit longer than your nail polish.

    The fact that TiN is being used by professionals around the world for implants is a pretty good measurement and test of it's durability in said situation. Real world testing and all that.

    Toxicity / carcinogenicity is not a measure of bio compatibility.  You are missing something. Go outside. Find a rock. It is neither toxic nor a carcinogen. Sterilize it. Implant it in your arm. Await the terrible consequences. Take pictures.

    Just saying something is acrylic means almost nothing in the chemistry world. I mean, it's a start, but that's like trying to id someone by saying they are human. It's a bit broad.... I'm not going to get more into all the issues with this uv nail gel thing.  It's been explained to death not only in this thread, but multiple places on the board.

    Also, i just noticed that Thomas said uv curing gel and you said uv nail polish! Ah! These are totally disparate things. Why are we talking about this? How did none of us catch that.... -_-

    Lastly, saying that it's relative in the end... means fuck all.
    Please refer to analogy about implanting said found rock. There are some things that work and some that don't _in a certain situation_.  I mean, I could bury the rock and it doesn't harm anyone, so "it's all relative", but in the end I still can't implant a rock. So, it is all actually relative meaning that the definition needs to apply to the situation.. And we are talking about implants. Relative to implants, a surface must be biosafe. This means do the proper testing or use a previously well tested material.
  • @glims ;
    "Also, i just noticed that Thomas said uv curing gel and you said uv nail polish! Ah! These are totally disparate things. Why are we talking about this? How did none of us catch that.... -_-"

    Right? I feel like the only reason we are even still talking about this is because we want to keep someone from fucking themselves over... 

  • I didn't even have an intention to bring up gel. It was about the first thing my brain spit out when my mind was searching for a word.
    I'd agree with everything relevant has been said, all warnings issued.
  • edited December 2015
    hey, but I'm using uv gel. ... it's only, they sell it as uv nail gel. :)

    anyway, I got myself some gel yesterday... even if I don't end using it for magnets, my nails will welcome some lasting manicure.

    well, this is the ingredients list:

    Di-HEMA Trimethylhexyl Dicarbamate, HEMA, Hydroxypropyl Methacrylate, Trimethylbenzoil Diphenilphosphine Oxide, Hydroxycyclohexyl Phenil Ketone, Violet 2 (Cl 60725)

    now I gotta investigate if all those are safe (... non-toxic/ non-carcinogens)

    also, I just ordered some gold-plated magnets. so, the actual UV gel's mission is to protect the gold layer.

    and as for "just putting a rock", well, correct me if I'm wrong, but only "risk" would be rejection, right? okay. IMO that's an annoyance and a waste of time, but does not pose an actual health risk. right? ... then, I'm going to try. piercings also reject sometimes and nobody really cares (other than for the money and time lost).

    EDIT: okay, I just started my research. I found this: on the metacrylates. ... I'm no expert, but that seems to say that, except for really high doses, and some minor allergies, the metacrylates are safe. (please correct me if it says otherwise... )

    next I have to search for the other ingredients...

    EDIT: okay, TPO: looks like completely safe unless in extremely high oral doses. no, I'm not gonna eat it, lol.

    EDIT: and the last one, also safe:

    okay, guys. any reason (other than risk of rejection) to not try this? am I missing something?

  • edited December 2015
    Ok, I very much appreciate both your dogged determination and your use of academic sources, but NO THAT IS NOT WHAT THAT PAPER SAYS. "Weakly mutagenic in mammalian test systems" means that this material can act as a mutagen (increased risk of cancer, an actual health risk). The cytotoxicity results in that paper also say they observed dose-dependent cytotoxicity (it killed cells past a certain concentration). They tested in the micromolar to millimolar range, which is probably less than your cells will be exposed to close to the site of implantation. This means you make experience local cell death, which means impaired healing and possible necrosis. And do not try to extend studies of skin-applied methylacrytate (this study) to intravenous methylacrytate. I'm not even sure those exist. Think about the AIDS virus, HIV. On the skin it's harmless, but in the bloodstream it can destroy your immune system. The skin is a pretty excellent protection barrier. Methylacrytate appears to be both toxic and a mutagen.

    To test if it will kill you or just do some damage, you can cure a dab of the nail polish, place it in 98 degree Fahrenheit saltwater for a few days, and see what it looks like when you take it out. Not quantitative, but you'll know if it will readily dissolve in the main solvent of the bloodstream.
  • see, that kind of extra test is what I wanted to learn.

    anyway, the tests I linked are for the monomer ingredients - once cured, it turns into a non-soluble polymer (.... I currently have my nails coated in it, and can confirm that water solubility of the material is almost zero... though I'll totally do the test on saltwater, since I have to wait for the magnets to arrive, anyway)

    also, "weakly mutagenic" IMO means, well, yes, it's mutagenic, but only weakly. i.e. chances of it producing mutations are low, and then, chances of those mutations being actually nocive (actual cancer) are even lower.

    I've also read some more papers on the metacrylates (I can link them if you guys and gals want), that also say that they're pretty safe (yeah, again, for dermal use...). yes they can cause irritation and sensitivity, but the first is tested out but putting some gel on my finger and confirming that I have no reaction, and the second, well, if after a while starts giving trouble... I guess I'll have to take it out (i.e. not the end of the world)

    as for dermal vs intravenous... okay, this is not dermal, but is also NOT intravenous. it won't be able to flow through blood. it's actually intradermal. (or am I too misinformed?) anyway, the first paper did talk about iv tests. ... probably in relation to lethal doses, and for sure in a monomer (non-polymerized) state.

    anyway, thanks. I'm sure I will be making less big mistakes thanks to you all. :)
  • edited December 2015
    Not to derail the wonderful biocompatibility theme going on, but let's consider/investigate some of the physical properties of this gel.
    Some of the things I highly recommend you find out before coating your magnet/s in this:
    1. How does it cure? (Get a magnifying glass, or better yet, a microscope, and examine the surface and the layer) Are there bubbles? Is it rough?
    2. How durable is it? (Does it flake off? Does it scrape off easily? If you hit it with a hammer, does it chip, or will the magnet break before that happens? If you implant it in a piece of pork, put the pork in a paint shaker for 24+ Hours, and then remove the magnet, has the coating been damaged at all?)
    3. How well does this gel work with the gold coating?(If a chain is only as strong as the weakest link, and the gold can be rubbed around, will forces applied to the gel affect the gold, and cause the gel to crack/flake?)

    Engineering aside, you also need to find out if it's sterile, and if not, how easily can you sterilize it. Will the UV light kill everything in there? Can it be contaminated by the coating process? Will it promote microbial growth(a pitted surface)?

    And finally biocompatibility. In addition to finding all of the papers, and after you've determined for a reasonable doubt that you won't have a horrible reaction to it from that data, I recommend curing a dab of the gel, doing whatever your can to make sure you get all of the solvents out, and then implanting it somewhere "safe", as suggested in previous comments. Doesn't even have to be on a magnet. Just mark the site, and watch it. You'll know pretty quickly whether it's going to reject or not. 

    Practically, How do you plan on coating the magnet? Painting nails is one thing. Applying a thin coat to a pea is quite another.
  • 1. it cures completely shiny-smooth. no need for a microscope or magnifying glass, it has a mirror shine. (any rough surface won't uniformly reflect the light... )

    2. quite durable. I've used the cheaper one on my nails as nail-extensions. I'm quite rough with my nails, yet it lasted quite a while without chipping/breaking/whatever. 

    I'm now trying the new one (the one I plan on using) on my nails. but I already feel that the quality is so much better - I don't expect it to chip or break in a reasonable amount of time, even though I'm tough on my nails. (so, chances of chipping or breaking in a protected environment are slim to none)

    of course, it's not steel-hard, but inside the skin, it won't be subjected to such kind of abrasion.

    as for impact resilience, I'd say quite high. it's a pretty flexible plastic, I tested the old one on my nail extensions and it would stand against pretty rough use.

    3. of course, I gotta test that as soon as the magnets arrive. but I'd guess it will stick quite good. also, shall it "peel", the layer is strong enough to not break (so the magnet would still be sealed under the gel - even if not sticked to it anymore)

    4. re: sterilization, I gotta see what happens if I rub it with iodine. but the main concern with poor sterilization is infection risk - I'm already aware of that one, and I'm willing to take it (... I'll just say I'm not prone to infections)

    5. biocompatibility: honest question here. is it such a problem to implant it on the finger, and let it do it's thing? i.e. is a rejection on a finger THAT bad? ... I'd think greatest risk would be of getting a scar... am I missing something?

    6. re: how to coat it: ... exactly as my nails. put gel on one face and sides, let it cure, repeat, second face, cure, repeat. two layers are hard enough, while still very thin. I've already coated small things. this won't be especially easy, yet I think  is totally doable.

    thanks for all the questions. being able to answer them means I'm not really messing this up. :)

  • edited December 2015
    EDIT: you keep asking "am i missing something?" and then we say yes, list of things. and then you just shrug it off.
    if the biocompatabilty fails in your finger, you may lose the finger, get scar damage, or lose nerve use in the digit? Am I being clear? Do you like your fingers?

    I am in so much pain right now. It's been a while since posts have hurt this much.

    We need to have a little talk about how to read scientific papers. When something is weakly mutagenic, it's still mutagenic. How normal people talk about things and how they are written in a science paper are not the same. Let us replace the phrase "weakly mutagenic" with "casually smacking in the face".  So, studies show that the subject is not being punched, however, they are experiencing being casually smacked in the face, repeatedly
    Now, how long does that sound fun before it just turns into a fail situation?

    So, the rock would have more issues than just rejection. Most importantly, from a biocompatible view, the buildup of fouling around the implant would most likely cause necrosis and possibly a stroke. So not just losing the implant, but the area around it, and maybe brain bits.


    HEMA swells after long exposure to liquids, high hydrophilicity tends towards fouling and biocontamination. In fact, all of these things are ok for putting outside your body. It all relative ;) Relative to your skin, these chemicals are ok, relative to your inside bits, they are not.

    If something isn't safe to eat, it's less safe to put inside your body in other ways.

    HPMA is not supposed to go inside your body.

    Intradermal vs intravenous on a chemical level means a lot less than you think. Are you positing that your dermis receives no blood? That there will be no blood contact with the implant?

  • edited December 2015
    I'd also like to a moment and talk about heavy metal poisoning. It's unpleasant, regardless of the degree, metal responsible, and temperament. I know someone's going to say that you can't get severe heavy metal poisoning from a neodymium that small. It doesn't matter. You've still been poisoned, and it's going to place an enormous strain on your immune system in that area. Throw a pathogen into the mix and you've got a brand new stub, unless you're very very lucky.

    Just to be totally clear, in case anyone is wondering, neodymium is considered a "heavy metal" in regards to how it plays with the body's chemistry.

    As for the surface, I'd like to take a moment and talk about blacksmithing, an experiment by @cassox (Or was it @chironex?), and mentos. Let's say I take a piece of steel and bend it in the same spot over and over again. It's going to do several things(assuming it doesn't break): 1. It's going to form microscopic fractures. 2. It's going to change color(Dull). You can polish the steel again after you've done this, and the dull color will disappear, because you smoothed the surface over the fractures. But just like a sinkhole, the fractures are still there, even if you put a few boards on top.

    As for the experiment, a piece of adhesive/resin was cured and looked nice and smooth. But under the microscope, there were a load of tiny grooves and nicks. In the words of an old space hermit, "Your eyes can deceive you. Don't trust them". 

    And finally mentos. Smooth, shiny, and covered with microscopic potholes. 'Nuff said. 

    In terms of sterilization, if you're not willing to go buy chlorohexidine and the other sterilizing agents described in the standard implant procedure, iodine and a few hours exposure to UV light MIGHT be enough to kill the worst of the pathogens. No promises. 

    As for coating. If the magnet is 1mm x3mm, regardless of your experience, you're going to have a helluva time getting a good coat without overapplying, and then grinding off the excess. Which is not a good idea. 

  • inb4 OP >your advice is nice but im gonna do it anyways
  • @glims: yeah, I keep asking "am I missing something?" 'cause it's usually related to different things. then you guys explain what I'm missing, and I don't really ignore it, I just look for a workaround (or provide a reasoning as to why I don't see it being as bad as you guys put it). then ask again to be sure I didn't mess up again in my reasonings.

    that's the reason why I do think that this can have a happy end: you guys are pointing me a lot of things that I would have totally missed. (so, my most sincere thanks for helping me in not completely messing this up)

    okay, back to the scientific talk.

    re: mutagens, why, that's not how statistics work. weakly means it has a small chance of.

     ie. out of 1000 cells, 1 of them will change. then you'll tell me it's gonna be in contact with a lot more than 1000 cells, and I have to agree. so, suppose, in total, 100 cells around it do mutate. okay, now, not all of those are gonna be cancer, that's not how it works. maybe, if I put enough cells, 1 out of 1000 mutated cells, will be malign (i.e. cancer). yet we said I had only 100 mutated cells, so chances of one being malign are below 1% (or maybe I messed up my math, but you get the idea).

    okay, that's ballpark numbers, but as an example, I guess it's good enough. what I mean, is, weakly mutagen, in the end, means chances of it giving cancer are small. a strong mutagen may mutate more than 50% of cells. so there you (I) have a problem.

    also, on another example. granite is radioactive. and we all know radiation produces cancer. ... yet since it's only weakly radioactive... you guess it, after long exposure to high quantities (i.e. your whole house made out of it), it WILL give you cancer. shorter exposures to lower quantities decrease the risk, to the point that they use it in a whole lot of buildings, and nobody has tried to ban it for giving cancer.

    okay. now the rock. see, I did not know that. (that's why I keep asking :D ). what is that fouling buildup? just sebum? something else? ... shouldn't the body just produce a thicker layer of skin to seal it? ... do people with shrapnel inside (... that can include rocks and rusted metal) have that problem?

    in case it is as bad as you make it sound: how long will it take to get there? ... will I notice it soon enough? (i.e. if it takes a few years to get there, and I notice it shortly, will removing the magnet and thoroughly cleaning the area be enough?)

    and okay. I'll listen to you all and do a test first in other place (like the leg). :)

    as for HEMA swelling, yep. it does (... according to the study). in its liquid, monomer state. I have never seen cured  (polymerized) uv gel swelling under wet conditions, though. though I gotta keep an eye on my nails to test the new gel, today they had an encounter with water, and they are still perfectly fine. no swelling or anything.

    as for eating, well, nope. the stomach acid WILL dissolve a lot of things that blood can't. then the dissolved things will be absorbed into blood and distributed. while a solid piece in contact with blood will just sit there (... yeah, I gotta test the solubility in saltwater... ).

    also, intravenous vs intradermal, well, I'm pretty sure you can't put a solid object inside your veins. also, as long as the blood doesn't dissolve it, being in contact with blood means very little (... let's forget about infection risks since it is not what we're talking about now). (again, gotta test saltwater solubility... and maybe blood solubility too. extracting a few blood drops and putting the coated magnet on it doesn't seem a bad idea)

    anyway, thanks again for all your insight. I would have messed this up very badly if it weren't by you all. (or maybe not, but being sure of it before doing it IS a good thing )

    TheGreyKnight: okay. metal poisoning is the reason I'm investigating protective covers. but, as long as the neodymium (... the actual magnet) doesn't come into contact with my body, I will be safe. okay, I gotta test it for leeches (i.e. not only testing the cover's solubility but its impermeability too), but if it passes the test, then metal poisoning shouldn't be an issue.

    also, re: surface, why, yes. but you've polished it after!! and it's not even transparent!! there's no way a glass of any kind can be completely transparent (yes, the gel is transparent) if it has any kind of internal defects. ... and yes, the cured, untouched (i.e. no further polish) gel product, is not only completely smooth, but also completely transparent.

    yet, that mentos test seems like a GREAT idea to test it's surface. so I'll try to get some mentos and do it. (btw, I assume the test was: cover some mentos piece on resin, cure it, and then drop it into cola... right?)

    as for sterilization, okay. I can say I'll do that. (I won't. ... I have a strong immune system, and am not concerned with the usual infection risks. I've had a ton of wounds, my usual care was to lick them, and never of them ever got infected. )

    and for the coating process, well. I didn't say it will be easy. just, it's totally doable. also, I've ordered a few magnets in case I can't get it right the first time (... common Neodymium magnets are so damn cheap... )

    and again, thanks for your insight.

  • But you don't put the granite in your body. Also, 5% of the granite "is concerning", so yes, it actually has been discussed. They even have a testing process to keep the radioactive granite low, but they don't really do it.

    Much like when we say look at this thing under a microscope, soak it in salt water, etc, and your response is, sigh ok, my leg.

    Fouling is your bodies natural reaction to having foreign things in it. Your body doesn't make skin pockets when you implant things.

    Uv crosslinked polymers swell all the time (source: 4 years working in chemE lab working with, among many things, uv crosslinked polymers). Splashing water on your hands isnt like sitting in a vat of blood.

    I keep trying to sequentially address the things you say, but i'm hitting a wall.
    Have fun with your project. Take pictures.
  • Meh. We'll see how it goes. Something placed subdermal isn't in contact with blood. Blood contact really is a whole different ball game. The only reason swelling would be an issue is because it will cause a breach in the coating. Ok, can you tell me the specific brand details?
  • edited December 2015
    okay, I'll look deeper into the whole mutagens thing. and if being inside really is that much difference over it being outside my skin (I'm never good at not putting the thing on my cuticles... ).

    "Splashing water on your hands isnt like sitting in a vat of blood."

    how about taking a hot bath for quite a while? does that count?
    "Fouling is your bodies natural reaction to having foreign things in it.
    Your body doesn't make skin pockets when you implant things."

    okay. people get piercings all the time. some even acrylic ones, none the less. yes, those produce some sebum. but that's all. it doesn't cause necrosis or anything, actually (yeah, I have a few piercings).

    oh, and aside from sebum, yep, it does create some kind of pocket of thicker skin. at least on my piercings.

    @ cassox, okay, someone wanting to do some actual risky science. that feels good, man. :)

    the gel is this one (it's the base/top coat with primer). I already listed the ingredients, but I could post pictures if needed.

    also, the lamp is not the one from them, but it cures their gel really well and fast.
  • Something placed subdermally is in contact with many bodily fluids, including the blood making its way to the dermis when you do the initial implanting. It heals around but still.... I'm not saying it's like putting it in your veins, but you're going to have fluid contact.

    And yes, that is the reason that I was concerned about the swelling. Completely alters the mechanical properties.

    @niky45 Piercings aren't implants.
  • A subdermal implant is not in contact with blood beyond the blood during Implant. Medical implants in contact with blood require an entirely different set of surface characteristics from those that do not. Epithelial tissue is avascular. The blood beneath the dermis is all compartmentalized within capillaries.

    The thing is, the main reason actual blood contact is a big deal is thrombus formation. A clot in a vein can kill you. There are also some differences in term of immune response.

    I'll work on this today.

    Hey another thing to consider about the mutagenicity is time. You're right about the stats.. maybe 2 in 100 eh? But over how long? What would the percentage be after a year of exposure? I don't know.

    Niky, I think you're probably right about it being only mildly toxic. It's most likely not going to be a big deal. It'll just reject. I have zero faith in it being a suitable coating though.. the body is very good at breaking down or isolating materials. I'll go through the data myself and then advise based on what I find. The reason youre getting a hard time right now is because a lot of us are simply waiting and wondering whos gonna be the first person to bite the bullet in grinding. Cause it's going to happen. Itd be a shame for it to be something like a stupid coating failure.
    If someones death results in some bad ass new brain implant that changes the world... cool. But coatings? Meh.. not worth it.
    I think as a community though this can serve as a good example as to how to identify or rule out a coating. I mean, if we go through and predict that it will reject acutely and it does.. that's cool. Actually implanting it shouldn't be necessary, but if you choose to do this it is your perogative. Some people cut themselves for fun. I'm not being condescending or anything here. No shit. In fact please write up the process with Lots of pics and take extra care with sterility. This could be a doc showing the difference between rejection and infection.
  • @Cassox Thanks for clarifying that (about the blood). There are other fluids though, right? I mean, it's the body. It's gooey. If there was a breakdown of coating, the contamination would could be quite small and I would worry about transference. Again, maybe not to blood, but the surrounding tissues would have issues.

    @niky45  He's right, we're all just trying to be as safe as possible while doing things that are not considered safe by the general polulace. It requires a lot of self regulation within the community. Beyond the obvious legal blows that could come down, it would just suck if someone got really hurt. I've had the same concerns aimed at things I've done. That's why we talk about things here. So we can pool what we know and get advice and sometimes a bit of restraint.
  • may I suggest to use a proven to be harmless dummy for coating tests instead of actual magnets? like HDPE or medical grade stainless steel.
  • Glims, I wasnt trying to correct or anything. My point was simply that we should worry about what a coating does to the blood, not what blood will do to the coating. The other constituents of fluid are about the same anyways so if the coating is shit, it'll fail regardless of where it.. for the most part. I could argue some stupid fine points but it's mostly irrelevant. For example, the scrotum and cns does react differently. Of course Rich is the only one I know who need to be concerned. Ha.
  • Di-HEMA Trimethylhexyl Dicarbamate
    CAS: 41137-60-4
    So first off, this is synonymous with Diurethane Methacrylate which is a more common label. Here is an MSDS for the material: 9007 Diurethane Dimethacrylate.pdf
    Although there are issues with irritation, this is before being crosslinked. I’m familiar with this stuff as it’s also a component in all the dental resin crap I’ve tried time and time again. Here’s a patent discussing it’s use as a biocompatible orthotic filler:
    You might dig a bit deeper as this is a tad old and discusses other material that I know for a fact contain Bisphenol A which is now a no no. Here’s another patent of interest:
    This is a spinal implant that proposes to use this material as well. Overall, I’m going to say this is safe for implantation.
    HEMA – Hydroxyethyl Methacrylate
    CAS: 868-77-9
    Ok, so we run into an issue here with the MSDS:
    If you go by the MSDS data, it’s a suspected carcinogen and causes reproductive harm etc. etc. The thing is, these MSDS forms are for the material as manufactured… in other words with agents that prevent crosslinking from occurring until you want it to. So really most of those effects are probably from the ethylene oxide rather than the monomer agent itself.
    Evidence of this? It’s used to make soft contact lenses. This is good in terms of biocompatibility BUT, this stuff absorbs like 600% its weight in water. It’s like a hydrogel so I don’t think it would rupture per se. Methacrylates are pretty biocompatible.. but I think this is likely going to be a source of fouling. It’s a perfect surface for it. Think about how nasty contact lenses get. Similar concept.. of course we don’t know the percentage so it might actually be pretty minimal.
    DEFINITELY do some testing in regards to water diffusion through the coating. I have a feeling this stuff is practically porous.

    Hydroxypropyl Methacrylate
    CAS: 923-26-2
    This is another methacrylate. Interestingly the non-crosslinked monomer even in powder form is a category 1 irritant meaning it causes reversible skin damage within 4 hours of skin contact. Well, I doubt that the crosslinked version does the same. It has many of the same types of warning as the previous methacrylates that are mostly due to the agents keeping it a liquid.
    Regardless, there’s a great study about it here:
    Testing of subcutaneous implants with this coating appear to show it to be rather safe. Weird.

    Trimethylbenzoil Diphenilphosphine Oxide
    CAS: 75980-60-8
    This is your photoinitiator. This is not something you want to put in your body. It’s a reproductive toxin and sensitizer.. in liquid form. In solid form.. it’s not too bad apparently although it may still be a reproductive toxin. Take a look at this study:
    Unfortunately I don’t have access to the fulltext, but it basically says that the level of cytotoxicity is dependent on the reproductive rate of the cells. Seems a tad sketchy but take a look at this one:
    This study found that at low levels, the compound is cytocompatible AND the methodology is explained.. they put the shit on the cells wet and then placed it under a UV light. They cured it right on the damn tissue! Since you aren’t planning to use this method.. it just might be ok.
    So far.. this initiator is the worst thing. I don’t know enough about these materials to know if the crosslinking process under heat, uv, vacuum or whatnot will remove the photoinitiator. If it does then this is moot. If it doesn’t, I’m very curious as to the concentration found in your product.

    Hydroxycyclohexyl Phenil Ketone
    CAS: 947-19-3
    MSDS: Aesar.pdf
    This appears to be another photoinitiating chemical.
    It’s widely used in the production of stent:
    Heres a study showing dose dependent cytocompatibility:

    D&C Violet #2
    So first off, it’s a mutagen at least for bacteria and yeast. Now the weird thing is that a lot of cosmological sites seem to list it as a potential carcinogen. The source was listed as being from Silent Spring's Mammary Carcinogens Reviews Database. If you look it up in the database, it lists Violet 1, but not 2.
    It turns out that this die is on List 7 of the FDA color additive inventory meaning its used to die medical devices. For example, it’s used in color contact lenses. Overall, it’s not really intended for implanted devices, but it is used in constant contact with cell so it might be ok as well.

  • So.. I don't know. It doesn't seem to be as bad as I expected. The main concerns are the agents that prevent crosslinking, The methacrylates in general are pretty good compounds. The photoinitiators appear to check out in terms of cytocompatibility. I definitely don't like the die but I can't find anything showing it to be horrible. I'm actually really curious how this will work out. My prediction (ignoring that you're going to use gold) is that something made of this would fail because of the Hydroxyethyl Methacrylate after a couple of weeks. I'm not sure though because the mix of different methacrylates may make up for it. If you even have a modicum of success it'd show us the potential of methacrylates. I'm interested to see how you fair. Anyone else want to give it a shot? Also, what tests would people suggest? I'll hold off on suggestions for a minute.
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