An exploration of coatings

So as of writing we are in the process of updating the wiki I thought it'd be good to get a more updated coating thread as much of the others were scattered or outdated. We know that the best coating for magnets is TiN. Until something new comes out that's the standard. But as we hope to move past magnets and onto bigger and better things we need to discuss coating other items. If it's a small electronics package titanium works but I'm thinking smaller. Let's discuss how we would or could coat items say the size of a quarter or smaller. Ideally coatings that are doable either at home or ina  lab setting that aren't going to wear out quickly. I'm working on a personal project for example that will be fairly small but I would like to avoid using glass and ideally avoid high temp.
So lets do two catagories with different criteria:

1. low temp and easy (not good for magnets but good for other things)

Roomtempish curing
easy enough to do at home
ideally fairly inexpensive
Biocompatable (obviously)
Limited to no fouling
Doens't need to be hard, can be squishy so long as it doesn't rip
So strong and hard to fragmet

2. Hightemp and higher tech (lab setting or company sendout) (rfid stuff, magnets, transdermals, etc)

Biocompatable (obviously)
Limited to no fouling



  • edited October 2015
    Ive been following the coatings discussions going on and while i was surfing the web (do people still say that?) I came across this article about a new nanofiber coating system that can also deliver antibiotics to reduce the chance of post-op complications that can trigger a rejection of the implant. It could go on over the biocoating if i understand it correctly. I havent seen anything like this in conversation so keep it or kick it, its not my field of study.

    Its a short read though but i figure it wont take much for you guys to source more info. It may be worth looking into if it can be done without crazy complex wwii vacuum monsters or heat. It doesnt discuss the characteristics of the coating.

    It doesnt list sources either so it could be misinformation. Ill leave that for those in the know.
  • Far as I can tell it's a lot of speculation. nothing concrete. if you find sources i'll happily give em a look and see if there's more to this.
  • bingo, found something.  Its an electrospun nanofiber coating that takes well to Ti. 

  • Sorry to double post but im having problems posting from my phone.  Anyways, i will keep looking into coatings. Im a machinist by trade so im familiar with electrocoatings and anodyzing and such.  I studied with a few biomed guys at Indiana Tech and gained a basic understanding of implants and and compatibility.Just enough to intrigue me now that im seriously considering an implant.
  • that looks similair to what we're working on with the transdermal. HA is pretty common, they just used it in a slightly different way
  • edited October 2015
    I read up on a little of the HA work.  It seems like the fibers can be made from a variety of feed stocks. I have machined a few material i recently learned were so medically important, PEEK, PE, and Teflon.  While mine probably isnt medical grade it got me wondering if any of these materials can be vapor deposited reliably at lower temps.  PEEK may be out if its hardness makes it too brittle. Otherwise i dont know the microqualities of it. if i remember right, teflon typically cures around 500* f but then again TiN used to require high temps as well but that problem was overcome. PE seems like a middle ground in terms of hardness. I havent read about the different varieties of PE except the high density stuff used in joint replacement.  I wouldnt think the stuff i make liquid coatings (industrial paint guns and such) parts with is the same stuff.
  • I'm sure you have thought about it but I would include using "usual" house hold items to produce it AKA stove,oven,microwave etc.
  • there's a lot to read into when it comes to coatings. people have done many a Phd on them. everytime I think i've seen every kind of coating method I find 10 new ones. So ya you can coat anything in anything else you just need to know exactly what onto what so you can work around both materials. Like if you want a plastic on a metal, you're better off spray coating or dip coating than trying to vapour deposit. The fibres in this case are mostly just something for the HA to grow on. There are plenty of ways to do this already and electrospinning is fairly dangerous due to the high voltage needed. Since you can't actually touch anything while it's going and all that. im using an electrochemical method for my HA and it is super easy to do. Their method is a pain in the ass. it might work better, but the cost out weighs the benefit. That's something you always need to take into account.
  • edited October 2015
    I see your point about the plastics and yea the thickness of sprays or dips is a turn off.  Im interested in the nanofiber making process.  i read a little bit over the past couple days but mostly abstracts that dont go into depth on the process. One mentioned ammonium hydroxide.  

    for magnets I think microwaves and ovens and such may produce more heat than these guys are wanting to work with.  The m31 and other neo magnets have a curie temp of around 300*F.  The closer it gets to the curie temp the more guass is lost, some irreversable.  Hitting the curie changes the alloy and effectivly kills the magnet.

    (Edit) i applogize for my tunnel vision, i have been focused on magnet coatings. Im not familiar with rfid tags or other electronic implants but i would think those cant be heated much more than a magnet
  • edited October 2015
    in keeping with the initial post format;

    Class one;
    order gold plated magnets (inert base coat), electroplate with rhodium as @cassox mentioned in another gold mag thread.  Im also finding papers that mention applying a thin coating of Ag to make the implant temporarily bioactive during the initial healing process then the body processes the silver leaving only the rhodium.  the paper mentioned using colloidal silver in the electrolyte as opposed to just a silver salt (partical size importance?)

    In other papers they integrated the silver in with Ti as some kind of alloy or specialized coating process that i didnt read into further.

    (edit; links added for Ag bioactivity)
  • the simplest and seemingly best method I've seen is simple electroplating of HA onto a surface. It's interesting that they included silver. Personally I wouldn't since silver is more of a gimic than actually useful. Silver nanoparticles are not inert by any means which means over time that'll dissolve and could irritate the body and cause rejection. While I like the idea of incorperating an antibiotic element i'd sooner dip the thing in antibiotics than use silver. But I may be biased to silver since I think it's overwhelmingly boring since it's inherently expensive. However that said, i'm testing some of my nanoparticles against a bunch of bacteria to see if they have any antibacterial properties. My particles are far cheaper so would make for a better option than silver. 
  • edited November 2015
    Has platinum ever been considered as a magnet coating? A runner up to that being palladium. Both metals are extremely corrosion resistant, however palladium will cause a reaction if you are also allergic to nickel, the reaction wont be nearly as severe because palladium looses atoms at a much slower rate than nickel.

    Platinum is also a fairly hard metal, so it would be fairly abrasion resistant.

    The metals can also be electroplated on so there is no damaging temperature involved. I do think though that the magnets would need to be plated in gold first for good plating adhesion. And with gold being the underlying plating any pinholes in the platinum would only expose gold underneath, an also bio inert material.

    The plating is only microns thick as well, so it wouldn't disrupt the strength of the magnet.

    Platinum is also not magnetic so the plating process in theory shouldn't be disrupted.

    If they have been tested and or considered what were the pros and cons?

    Unless I am  missing something huge the only problem is the price of the plating.

    If no one has tried this and no one can present a valid reason it wouldn't work I am inclined to try it and would be happy to post my findings.

    I did do a search on here and found only a few mentions that platinum would be acceptable but I would like to go more in depth.

    I am open to any comments or suggestions.
  • do you have a lump of platnium laying around? cause if you do, fuck coating magnets with it I can think of a thousand better uses for it. Sure it's been considered but realise most of us are broke or dont have huge cash to throw at this. That coating would cost more than you'd think to get onto a magnet and it'd be difficult to make it as perfect as it needs to be.
  • Yeah, kinda cost prohibitive. If you have the means, do it! Let us know how it works out.

    One thing that you will see if you look around for platinum as an implant, is that most people always end up coating it in something else. Which raises the question, if this would work as an implant coating, why are other people coating it in something? Make sure you check the previous research to get a perspective on that so you don't just spin your wheels.
  • To get a full electroplating system is extensive but not that bad. It's on the order of a grand. Also there are places you can send it to be electroplated.
  • This may end up having to be a home plating job, I called all the major electroplaters in denver and no one can even do platinum, I called jewelers as well and got the same response. I can get the platinum plating solution from the uk for fairly cheap about 80 bucks or so.

    Palladium on the other hand is much easier to come by in the us for about the same price as platinum.

    The easiest by far is Rhodium, almost any jeweler can plate that directly to nickel or gold. Rhodium solution can also be purchased for cheap online.

    So in response to why people are coating in everything but platinum is most likely the difficulty in obtaining it.

    Ill do some more reading on if rhodium is a good option, if not then ill prob go with palladium.

    Another other option is just straight gold plating, in talking to an electroplater they have several variations of gold plating from some very hard plates to some very thick plates upwards of .00050" and they're set up to do it so it would be a lot less painful cost wise.

    Oh well if I can't find a plating then at least I can say I tried, I can only imagine what you guys went though in just trying to find titanium nitride.

    Thanks for your input your experience in this matter is is worth more than platinum haha.
  • what i know about rhodium is this, biosafe, platinum class, durable, common plating for white gold, can be plated at home. 

    i wonder, since Rh has been known to wear off of jewelry as its worn how is this likely to translate into implant wear? It sounds like a winner if the durability factor is high.  I'd like to try rhodium plated over gold since mags can be ordered in gold then could be Rh plated at home.  Ive got most of the parts i need for my power supply, just gotta find time/energy.  My priority atm is getting my other truck on the road, though. My daily driver needs parked for fixin.  plus i promised id give my wife a tattoo this weekend. Busy busy 
  • That too is my concern with Rhodium; the wear resistance factor.

    I was recently quoted 5 to 6 dollars a magnet for platinum plating, he did not really want to bother with this though, they take extra effort to plate because they're tiny and stick to everything. He referred me to another company but I have yet to call them.

    Multiple jewelers however, don't seem to have any problem with rhodium plating a bunch of tiny magnets. So that may be the best option. I might get some plated just to see.
  • I think the reason it wears off so easily is because they do very very thin layers. You could probably get a much thicker layer by increasing immersion time. Also there is some deal with electroplating about electronegativety or something that determines how well you can plate something. Obviously rhodium will coat to gold.. It's done all the time. I trial getting some titanium units coated but it really doesn't work.
  • Hello Everyone,
    I have my own jewelry business. Platinum does wear out a lot faster. Most of the items I electroplate are finished in rhodium. It holds up to more wear than most other coatings. Most rhodium coatings last about three to five years on a ring. Under the skin I imagine a lot longer.

    I am going to plate several and implant two of them. The ones I plan on using is N45  6mm x 3mm. I am going to remove most of the coating and plate first with copper and then in rhodium. If the platimg os too thick it will flake off.
  • edited November 2015
    Outstanding! @cassox, how would you compare abrasion a wedding band might face to that of, say, a finger mag in a pinky?

    @puzbiks1, where are you putting your mags? And what are they coated with that need be removed? If the Rh coating were to wear though, your blood will eat right through that copper and into the Neo. Toxicity, not good. If they are coated with nickel and the above happens, it still eats through toxic materials. Not good.  Help me understand your reasoning. Im not sure if that is enough copper to metabolize and become toxic also.
  • edited November 2015
    That's the main reason I want a gold plating underneath the platinum and or rhodium. If there's a defect in the top plating there's a good chance that the gold underneath will not corrode.

    I was also looking at a way to suspend the magnets between two pieces of bismuth and then adding a piss thin layer of UV harden dental composite resin.The bismuth repels the magnet allowing it to float in mid air and then you can apply a layer without the mag touching any surface and also vacuum de-gas the resin before hardening.
  • edited November 2015
    What about medical grade silicon? I also found these, I get a bad gut feeling from them. I think its that coating.

    Also is there anything I should know about melting down silicon? Like sterility procedures temp warnings, may be smell I shouldn't smell. Someone here as to have melted the stuff before.
  • Silicon doesn't get melted and then applied, it starts as a combination of liquids or sometimes a powder and a liquid. And it will smell, till it's finished.
    If you are melting it post cross linking, it will be useless.

    If you poke around, there are a lot of thoughts, both opinion and professionally based, on the use of silicon as a coating. The tl;dr is that it's better than nothing, and the best soft coating we have. Remember though, that the best thing that sucks, still sucks.
  • @minnella My magnets are coated nickel, copper, nickel. I am planning to put one on the side of the index finger and the other in the ring finger. The reason I want to remove one of the nickel coatings the more layers you put on it can chip.

    I can put on a layer of 24 kt over the copper, then finish with rhodium. I have plated rhodium on rings that is holding up over three years. Implanting it should last a lifetime. 

    I am open to any suggestions you may have.
  • edited December 2015
    Ya, we're thinking alike.  Let us know how it turns out.  edit, based on @cassox recommended sizes yours may have trouble healing and may reject. Hopefully he can chime in.
  • I'm not sure if this is legal (not that it really matters).... But as a biochem student, I have access to the above article...

    If it helps you guys out I am more than willing to contribute. I'm rather new to the whole biohacking thing, but think what you guys are doing is great! I truly believe this is the way to the future.

    Just wondering, and this is probably kind of an obvious question for those with more experience, but has anyone tried putting the magnets in a really thin glass coating? I'm assuming someone has and that there's a reason we don't do it... But why? And why don't we inject magnets like we do with RFID chips? Is it just difficulty with placement? Size? Etc?
  • I think for glass coating the heat is prohibitive.
  • But you could remagnetize. Does anyone know of another reason? It might just be that it's a weird custom job...
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