Gel patch extraction thoughts and ideas...
^Thank you to everyone who appreciates this thread and for the compliments! I'm really glad my time developing this method more importantly typing everything out here is not in vain and can help others.
I have a decent idea of how a similar extraction could be done with the gel patches. I read over that journal article abstract again and found some interesting stuff. I'm just going to post the entire abstract since it is all interesting and underline the key points of where I see potential for gel patch extraction. I recommend reading it all.
Abstract
The method development and validation characteristics are described of a simple gas chromatographic–mass spectrometric (GC–MS) analytical procedure to determine residual fentanyl in used Durogesic® reservoir patches and Durogesic® D-Trans® matrix technology based systems to estimate the actual rate of transdermal fentanyl delivered in individual patients. The sample preparation protocol constituting a saline based extraction of sets of new patches of each nominal dose available, resulted in fentanyl extraction recoveries to increase steadily as a function of increasing extraction time. For the reservoir type transdermal therapeutic system (TTS), fentanyl extraction efficiencies at equilibrium (16 h) ranged from approximately 60% (100-μg/h TTS) to 95% (25-μg/h TTS), whereas for the matrix type system considerable lower recoveries were demonstrated for the highest nominal dose rates (35%–52%), while reaching 90% for the 25-μg/h system. For the latter type of fentanyl TTS, an optimized methanol based extraction protocol yielded virtually quantitative fentanyl recoveries for each matrix patch nominal dose level at substantially shorter extraction periods (15 min). The GC–MS analytical method using selected ion monitoring (SIM) and deuterated fentanyl as internal standard was shown to be adequately selective with regard to the presence of other compounds in the Durogesic® patches. It was further demonstrated that the developed analytical protocols provided highly reproducible and accurate estimates of the initial fentanyl content of each patch type at all available nominal doses, with coefficients of variation and relative errors generally below 10%. These advantageous assay validation characteristics can be further transposed to the application of residual fentanyl level estimates in used patches, provided that with each batch of samples also a set of new TTSs with equal dose is assayed to perfectly mimic extraction phenomena. Finally, the presented GC–MS analytical protocol was successfully applied for the determination of residual fentanyl in a subset of 57 reservoir type patches obtained from four palliative patients.
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On the topic of how to potentially extract fentanyl from gel reservoir patches using a similar technique as above
Disclaimer: The following is all educated conjecture about how fentanyl could be extracted from gel patches. I have not done it and if you attempt this use more caution than ever and please do it for experimentation purposes to find a safe procedure for extraction that yields an accurate solution for dosing fentanyl. Attempt this in the name of harm reduction and the future benefit of everyone and please don't hurt yourself.
Do not attempt any gel extraction methods if you are just looking for a quick way to recklessly get high and abuse some patches you have sitting around. This has not been attempted or verified safe yet. Onwards...
In the study they basically first extracted the gel reservoir patches by letting them sit in a saline solution and the longer they were in the solution the more fentanyl was recovered. It also goes on to say saline wasn't effective for the matrix patches whereas an alcohol extraction yielded nearly complete extraction of fentanyl hence the process I described.
Now first let me say I have never seen a gel patch in person let alone used one or attempted extraction. My main concern and potential problem I see is isolating and not getting any of the gel into the final extraction. From what i read above it sounds like they just dropped unaltered gel patches in saline solution and were able to extract a significant amount of fentanyl. It doesn't say if anything else from the gel leaked into the extraction or if it was purely the fentanyl. I would think that if you don't alter the transdermal delivery mechanism or alter the patch at all then by letting it sit in the saline the fentanyl would be extracted leaving the inert gel with minimal leftover fentanyl inside the reservoir just as it works when you wear them.
I can't be sure if and what else would be extracted from the gel in the saline from this method. For that reason
I would not advise any IV use from gel patches until there is more information, research, and experimenting from experienced bluelighters about what else actually gets extracted and if it is harmful and can be filtered out through a micron or other methods.
So basically you would soak a non tampered with patch (aside from removing any protective film) in saline solution and let it sit. After letting it sit for several hours I would expect there could be 80% or more fentanyl extraction, perhaps 90%+ which would make it easy to adapt the matrix solution prepping/dosing method for gel patches. After soaking it for a while you would remove the patch and evaporate the saline. This would leave behind some salt that probably can't be filtered out but it shouldn't be a major problem. I would not apply any heat while soaking the patches in saline since I wouldn't want to increase the chance of other/more stuff from the gel being extracted.
Now evaporate the saline solution. After you have the fentanyl, salt, and whatever else came out of the patch residue, follow the same procedure I outlined for creating an accurate dosing solution. If the extraction can get up to 90%+ efficient then dosing should be nearly the same, perhaps the actual dose is slightly lower here but as always it is safer to overestimate.. I would strongly advocate more filtering with the gel patches and using a micron since there is the potential for there to be a lot more crap than with the polymer patches. It also might not be as big of a concern since I would definitely advise
not attempting to IV the extraction from these but it can never hurt to have a more pure solution. With plugging, intranasal, and sublingual methods it should be less of an issue. That's it for now.
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This is a related topic I've been thinking about. the only part of my original process for preparing the end solution I think could be changed is using vodka and the amount of vodka. I am thinking you could use 2 ml or 1ml of vodka then 2 or 3ml of sterile water to get a final 4ml solution without losing any of the benefits of ethanol keeping the solution sterile at 20% or 10%. It would definitely be more pleasant to take with all ROAs and require less dilution. I will probably edit this into my original post.
I should also mention it is important to keep the solution in a small sealed container so nothing evaporates which would change the concentration of the solution potentially making it more concentrated over time leading to higher than expected dosing which could be dangerous. That is why I really like and recommend the small 4-5ml sealed vials with rubber tops for inserting needles while still keeping everything sealed.