Skip to main content Link Menu Expand (external link) Document Search Copy Copied

DIY Journal

Welcome to our journal where we write about wild fantasies we have about catgirls what we’re actively learning on any given day. Thoughts may be incomplete and scattered, these are merely our own notes. Look at Topics and Guide for more structured info.

Silicone Stoppers are Cancelled

These seemed like a good idea due to their high heat resistance and therefore their ability to withstand dry heat depyrogenation. However, we located a study that has indicated that benzyl alcohol (BA), the essential preservative in HRT, can be absorbed by silicone and then even evaporate out the other side of it. While this hasn’t been studied in relationship to a preparation with a 1% concentration of BA, it stands to reason that as the preparation make contact with the vial stopper it could, rather quickly, remove the preservative from the vial.

This is of much higher concern than a stopper that did not undergo depyrogenation. we are switching the guide back to using butyl rubber. We will use a minimum of autoclaving the stoppers for a sterilization cycle. We will look further into using pressurized WFI at home to depyrogenate. This is probably out of reach or asking too much of the average homebrewer. we’re sad to have lost this easy method but grateful no vials have been produced with the silicone stoppers.

Vial contamination

why do a severe lack of sterilization practices in most DIY guides result in vials that are not causing infection en masse? our theory is that the benzyl alcohol in the vials is killing stray contamination. There are some studies that tangentially support that theory.

Final Sterility Testing

There is a sterility test that can be preformed on the vials, CSP pg 261, USP 71

The minimum volume of each CSP to be tested is dependent on the volume of the final product. If the product is <1 mL, the entire volume must be tested. If 1–40 mL, then half the total volume is tested. If 40–100 mL, then 20 mL is tested. If the volume is >100 mL, then 10% of the volume is tested (but at least 20 mL).

To do this you would decide how much of your preparation you’re testing, then you run it all through a 0.45μm filter. Then you can disassemble the filter, and put the membrane on agar. Incubate for 14 days.

After the mixture passes through the 0.45μm filter it is, in theory, still adequate for use as soon as the tests clear. Therefore, you could do a procedure like filter most though a 0.22μm filter straight into vials. Filter the remainder through the 0.22μm into a sterile and depyrogenated container. Then run that all through the sterile 0.45μm filter (clean syringe) while dispensing into vials.

This is not part of our procedure right now, but it should be. The issue we run into is regarding which type of agar to use for this. CSP pg 262 says that USP says that it needs to be FTM (lol) or SCDM agar, neither of which appear to be readily available for the public to purchase or to even make at home for less than hundreds of dollars –

#TODO - finish section on sterility testing, revise the rest of the guide to reflect.

1 week later

Okay so scratch some of the above. This seemed more difficult to manage because the USP uses a weird naming convention for their agar types. What they call SCDM (soybean-casein digest agar medium) is typically referred to as TSA (tryptic soy agar) within the scientific community. TSA powder and plates are both readily available on Amazon for just shy of $50.

It would be good to do more research on the second type of recommended agar, FTM, to see what the primary difference is between TSA and what types of growth it supports. Using one of these is better than none.

Additionally, need to look into what type of agar is needed for fingertip testing.

What does heating a sealed vial to 120C actually do??

We can confidently say that the air inside the vial is heated to 120C also. When air is heated that much it should expand a relevant amount.

According to this Quora answer we can use the Ideal Gas Law to calculate the pressure changes.

103.4kPa x 393/293 = 138.7kPa

assuming we start at 15psi and 20C, and we heat to 120C, we end up with a final pressure of 20psi inside the vial.

Let’s crosscheck that pressure value with moist heat sanitization.

moist heat sterilization requires a pressure of 15psi. Not sure how to rectify that with 15psi being like, literally what is in our living room rn according to the internet. Maybe the moral of the story is that we need steam. No one says to sterilize with pressurized dry heat.

Benzyl Benzoate (BB)

May 29, 2023

There are reports of this ingredient not being needed as it’s primary purpose is to act as a solvent. Hormone esters are oil soluble, and so they will likely reach solution without it and with using a little heat. Unfortunately this could lead to preparations falling out of solution with dramatic environment changes, just a theory.

Looking further, it appears that every recipe we can find online both from DIYers and pharmaceutical companies list benzyl benzoate as an ingredient. Being unable to find verifiable information at to why this is, we will take it as a near certainty that we’re going to want the solvent boost in our brew.

Once we have more space around this project we may perform a set of experiments with E En, MCT, and BB to determine what’s needed to get it to fall in and out of solution at various concentrations. In the meantime we need to finish building this guide and there are more important questions to be answered, like “will anyone read this?” and “how many people are going to attack us in our DMs for claiming that using an autoclave on a sealed vial is pointless and has no supported scientific basis?” and “how do we make this logo look good at all screen sizes?”

Material List

Reddit r/steroids


Three common pharmaceutical packaging components are ampoules, vials and stoppers. Each component needs a specific depyrogenation procedure due to its chemical properties. document

great comments on reddit

depyrogenate glass, stoppers, and lil foil bits. after removal from oven, cover vial tops and stoppers in foil to protect. puncture aluminum to fill vial.

USP 1228: Depyrogenation - consider looking at USP 1211, it may have some methods for depyrogenation that are slightly out of date.

USP 381: Closures for Injections

Might be in the weeds on the question regarding how to depyrogenate the rubber stoppers. But also, it’s a very valid question. It seems to be largely overlooked within a DIY setting and in laboratory conditions there are tools to do the testing we’re not able to do.

we’re going to rest at this point here for now:

  1. Butyl rubber stoppers might lose integrity if dry-heat depyrogenated.
  2. Silicone rubber stoppers are significantly less likely to lose integrity if dry-heat depyrogenated, due to silicone being strong af.
  3. Using pre-sterilized vials sounds ideal, but there is a major downside of piercing a vial and then putting it in storage. we’re unable to find ANY information relating to doing things this way.

This makes silicone stoppers sound like the best option. Because this is a less common material we feel the need to check compatability with MCT, BA, and BB.

Depyrogenation 200C for 60 minutes - may be more compatible with silicone

PTFE/Silicone septa max temp 200C

There you have it. Use silicone stoppers and dry heat depyro at 200C for 60min.


See USP 1228 for information about Depyrogenation transfer. The effectiveness of the dry heat depyrogenation cycle must be verified using endotoxin challenge vials (ECVs)

A product may be sterile but still pyrogenic because of the presence of bacterial endotoxin.They can be difficult to remove from solutions but can be rendered inactive or destroyed by heat

Dry-heat depyrogenation continues to be the method of choice for the sterilization and depyrogenation of glassware. Depyrogenation uses a higher temperature and shorter duration than dry-heat sterilization (typically 250 °C or 482 °F) for 30 minutes (just within the threshold of most home ovens)

According to this document, glass vials need to be depyrogenated, while stoppers and caps can be sterilized.

According to Compounding Sterile Preparations, anything sterilized or depyrogenated needs to be done so in a container with a lid. This way it can be moved safely into the clean room. We will autoclave the caps and the lids inside of the clean room, however we still want to autoclave these things in a way so that they remain covered until they are ready for use. We will likely use aluminum foil wrapped in a way that allows steam penetration.

Reading Chapter 8

May 13, 2023

Build a clean room. The room needs to have high quality air filtration. Ideally this would be monitored but that seems unrealistic for DIY.

There needs to be a pressure differential between the clean room and the rest of your space. The differential isn’t listed. Logically we think it just means you need to have air flowing OUT of the clean room, not in. This could be achieved as simply as having your air filter get intake from outside the room and push the clean air into the room. Differential is supposed to be monitored but that’s unrealistic in DIY settings. Use simple tests such as dangling some string at the openings of the clean room to see that the airflow is blowing them out.

Recommended clean room temperature of 68F (20C) and humidity of 35-60%.

Isopropyl alcohol (IPA) 70% is the USPs primary recommendation on what to use as a disinfectant.

Info about Gowns and the order to put all garb on: pg127

“All compounding personnel must successfully complete an initial gloved fingertip/thumb sampling procedure (zero colony-forming units) no less than three times before they are allowed to compound CSPs for human use (Chapter 28)”

Reading Chapter 4

May 12, 2023

Because the bulk estradiol is going to arrive nonsterile the compounded sterile preparation (CSP) is considered “high risk”.

Use USP 797 requirements for cleansing, garbing, cleaning, disinfecting, etc.

BUD = Beyond Use Date

Institute for Safe Medication Practices (ISMP) best practices recommend verifying contents of CSPs using 3rd party verification. I.e., send vials in for testing after production.

There are more standards than can ever be kept up with in a DIY situation. How to pick and choose?

Reading Chapter 4. Make sure to read Chapter 18 later.

Find “Batch Master Worksheets”

“Pre-sterilized sealed containers should be used when feasible” does this mean the final product should go from syringe through filter through needle and directly into a pre-sealed sterile vial? and then distribute with a single puncture hole already in it?

Must do a sterility test to verify safety of contents. See USP 71.

So much of the guidelines require certain standards as to where the drug is coming from. Obviously is not on the list of approved suppliers lol.

This chapter has more to offer and needs to be revisited.

Reading about sterility assurance

May 11, 2023

Chapter 17 of Compounding Sterile Preparations. We need to learn how to calculate the Sterility Assurance Level (SAL).

Filtration is important. Unless filtration is terminal filtration it cannot be assumed to create a sterile end product. (What makes it terminal?) An explanation of features needed in the syringe filter are listed in this chapter. Filters must be tested for integrity after they are used and results recorded. See CSP pg 252 for diagram.

Biological indicators must be used when sterilizing by heat to help ensure that the sterilization cycle was effective.

There is also info here about using steam and dry heat. Dry heat sterilizer using a static-air sterilizer (basically an oven) is not suitable for most materials. Use 338F for 60 mins, 320F for 120 mins, or 302F for 150 mins. We imagine if using a kitchen oven there should be a thermometer inside to verify temperatures.

Steam sterilization (autoclave) is considered terminal sterilization, it can be used to to sterilize the product and final container.It is the preferred method to sterilize aqueous solutions and suspensions that have been verified to maintain their chemical and physical stability under the required conditions. How can we verify this with EEn or TEn?

There is a formula that will let you determine temperature/time/pressure ratios.

D = decimal reduction time (minutes). time to reduce microbial population by 90% T = temperature Z = number of degrees of temp required to change D-value one log unit in time by a factor of 10. If D at 121C is 2 minutes, and the z-value is 10C, then D at 131C is 0.2 minutes. We get what this means but not really how to find the needed values. F0 = idk?? it says this is a value but doesn’t actually define it.

100 microbes in a solution, reduced by 1D, 10 microbes left.

Always document autoclave details per batch. Temp, pressure, chamber config, num articles sterilized.

A dry sealed container will not be sterilized by steam, a small amount of water must be within the container to sterilize interior. Most oils and powders can’t be sterilized by steam as it may adversely affect the material.

Need to be able to verify the sterilization process was successful. How?

Use biological indicators containing Geobacillus stearothermophilus (USP Chapter 1035) to help determine that sterilization is successful. See USP 71 for sterility tests.

Primary takeaways

  • get the right filters
  • autoclave at the right temp/pressure/time
  • use biological indicator strips to verify sterility

Getting Started

May 10, 2023

we’re going to use this page to document our “bathtub estradiol” project in hopefully fairly substantial depth. We have spent several months researching how to make DIY Estradiol Enanthate injectable vials, and we’re coming to the conclusion that there is no definitively good resource on how to do this. There is, however, a lot of information floating around. Most full-blown guides are lacking a full explanation of why they’re doing what they’re doing, and additionally fail to hold themselves to what we consider adequate sterilization standards.

we are of the mind that if you are making vials for just yourself, and you make an informed decision to skip some sterilization procedures, then that is your right. However, it seems like most people who are making DIY vials do not have access to the right information for them to be making informed decisions around this. Worse then, when people use incomplete guides online to make HRT to distribute.

So, it is our goal to document our learning and brewing process in order to create a new standard for DIY guides. We will always be open to researched and referenced criticisms with the ultimate goal of creating the best open source guide we possibly can.

More to come.