Learn how to validate the shelf life of 70% Isopropyl Alcohol using Surface Swab Test and Settle Plate Method.
In order to efficiently conduct validation of diluted disinfectant storage condition and period, ensure that the following requirements are fulfilled –
· Validated Laminar air flow
· Calibrated Incubators
· Soybean casein digest agar
· Approved Test Methods for Swab testing and Plate
Exposure
· Test Organisms – E. coli, Salmonella abony, Staph. aureus, C. albicans, and Wild culture – WC1
Before proceeding for Validation of Shelf Life for a diluted disinfectant solution, following parameters are checked –
· Each lot of dehydrated media used for validation, the medium must be tested for its growth-promoting qualities.
VALIDATION TEST:
Validation of diluted disinfectant storage conditions is done by following methods
· Surface
swab test Method
· Settle Plate Method
1. Prepare 70% v/v solution of Isopropyl Alcohol.
2. Carry out the sterility of diluted IPA solution by Membrane filtration method.
3. Store the disinfectant solution at room temperature, and analyze the sample on the day of preparation, after 24 hrs, 48 hrs, 72 hrs and 96 hours by Surface
swab test, Settle Plate Method
SURFACE SWAB METHOD
Remove following culture slant from the refrigerator and allow it to attain room temperature.
· Staphylococcus aureus
· Escherichia coli
· Pseudomonas aeruginosa
· Salmonella, and
· Wild culture
1. Inoculate loop full of the culture from each slant separately into 50 ml of sterile Soyabean
casein digest medium and incubate at 32.5 ± 2.5°C for 24 – 48 hrs.
2. Transfer 1.0 ml of the broth culture into 9.0 ml of sterile saline solution (0.9% sodium chloride solution) to obtain a test dilution of 10-1
3. Transfer 1.0 ml of the 10-1 dilution into 9.0 ml of sterile saline solution to give 10-2 dilution.
4. Similarly serially dilute the culture suspension to obtain dilution of 10-3 ,10-4,10-5 and
10-6
5. Plate 1.0 ml of the culture suspension from dilution 10-3 ,10-4,10-5 and 10-6 in duplicate into sterile Petri dishes.
6. Pour approximately 15-20 ml of sterile Soyabean Casein Digest Agar cooled to about 45°C in each plate. Incubate at 32.5 ± 2.5°C for 24 to 48 hours.
7. Count the number of colonies on each plate and Select the
dilution, which gives a count of not less than 10-5.
8. Apply 1.0 ml of each culture suspension containing cell concentration not less than 10-5 cfu/ml, separately on the floor approx 25 cm2 area, and allow to air dry.
9. After drying, take a surface swab as per latest SOP for Swab Testing, and carry out the determination of total aerobic count per cm2 within 4 hours of sampling.
10. Immediately clean the floor with IPA 70% v/v solution and allow to stand for 30 minutes to facilitate the action of a disinfectant solution on the challenge test organisms.
11. After 30 minutes, take a swab and detect the bacterial count as per SOP for swab testing.
12. Repeat the same procedure, step no. 9 to 12 to determine the efficacy of
70% IPA solution after 24 hrs, 48 hrs, 72 hrs and 96 hours at room temperature.
SETTLE PLATE METHOD
1. Expose the pre-incubated sterile Soybean casein digest agar plate for 2 hours.
2. After plate exposure time, immediately clean the floor with IPA 70% v/v solution.
3. After proper cleaning, spray the area with IPA 70 % v/v solution and immediately close the room 30 minutes to facilitate the action of
disinfectant solution.
4. After 30 minutes of contact time, immediately expose the plate as per latest SOP for plate exposure and detect the bacterial count per location per 2 hours.
5. Repeat the same procedure, step no. 1 to 4 to determine the efficacy of IPA 70% v/v solution after 24 hrs, 48 hrs, 72 hrs and 96 hours at room temperature
ACCEPTANCE CRITERIA
Diluted disinfectant solution, which is stored at room temperature, is effective when the test result of surface swab and Settle plate shows 90% reduction of the challenged microorganisms.
Get ready to use editable documents in MS-Word FormatView List
Rubbing (Isopropyl) Alcohol is a fairly stable substance. Though it has a long shelf life, Isopropyl still does expire. Every bottle of Rubbing Alcohol or product consisting of Isopropyl as an ingredient comes with a shelf life. Depending upon the product, the shelf life can range from 1 year to 4 years and so. But what if the Isopropyl
Alcohol has gone beyond its expiry date? How good is Alcohol after the expiration date? And What do you do with expired rubbing Alcohol?
Relax and read further. This article has everything you need to know about Rubbing Alcohol, its expiration, and its usability further. Have a look:
Does Isopropyl Alcohol really expire? What is the shelf life of rubbing Alcohol?
Yes, Isopropyl Alcohol really expires. Rubbing (Isopropyl) Alcohol generally comes with 2 to 3 years of shelf life.
Or, if it is used as a base ingredient in any product, the shelf life may vary on its dedicated composition.
Though normally all the Isopropyl-based products last their best for a maximum of 4 years.
Beyond that, either it will cross its expiry date, or the Alcohol in the product will start evaporating, leaving it of absolutely no use.
When a bottle of Rubbing Alcohol expires, it still stays in use. It might not provide for the best of its usage but will definitely do for some basic household cleaning and disinfecting.
Even though its Alcohol content may have dropped down to some extent, the remaining solution and its accountability will do the job for some time.
However, if you have preserved the Alcohol bottle well for years and it isn’t evaporated much, it will still do its best job even after passing the expiry date.
How long can you store isopropyl alcohol?
One must store Isopropyl Alcohol ideally in an air-tight container away from direct sun and heat.
Considering its extreme flammable properties, one must keep it away from all and any kind of potential fire causes.
For keeping the Alcohol in its best form for long, one should avoid transferring the substance.
Consider maintaining the same until you are done with using the entire product from the same bottle.
Also, when not in use, avoid opening the bottle. If you do so, the Alcohol will evaporate, leaving the liquid of absolutely no use.
What happens if you use expired hydrogen peroxide?
Does hydrogen peroxide expire? Like Isopropyl Alcohol, Hydrogen Peroxide is also one of the common household substances. It cleans and disinfects household products and acts as a mild antiseptic. And like any other chemical substance (product), it too comes with an expiry date.
Inside an unopened bottle, Hydrogen Peroxide can easily last for up to 3 years. However, if you open the bottle, it is advisable to use it as soon as possible.
An open container of Hydrogen Peroxide starts breaking out quickly, losing its effectiveness.
Further, even if it has a long shelf life left, the product may not come of any use to you. But what if the bottle of Hydrogen Peroxide is expired? Can you use it?
Yes, Hydrogen Peroxide, when expired, can still come into use. If the user opens it just a few days before its expiry, the product may lose a little bit of its effectiveness.
In short, the quality of Peroxide or any alcohol product depends upon how safe have you kept it from evaporating.
- Can We Mix Rubbing Alcohol and Hydrogen Peroxide?
Hydrogen Peroxide is a relatively unstable liquid that decomposes within no time.
While some of the solutions can last you long, some might start decomposing inside a sealed bottle itself.
If kept as it is for years, Hydrogen Peroxide inside a sealed bottle will break down into water and oxygen.
And when you finally open the bottle, oxygen will evaporate, leaving just water behind.
It further comes of absolutely no use, as water is neither a powerful disinfectant nor a reliable antiseptic.
Does Ethanol have an expiry date?
Ethanol is simple alcohol and an organic chemical compound.
This popular solution is easily available in chemical stores and comes in handy for cleaning and disinfecting.
Both Ethanol and Isopropyl Alcohol have a connection, but they aren’t the same.
Also, as all types of alcohol have a particular shelf life, Ethanol comes with an expiry date.
What is the shelf life of 70% ethanol?
The Shelf life of 70% Ethanol can range from 2 to 3 years depending upon its manufacturing company.
While it is advisable to not use it after its expiry date, the product won’t still go bad. But as explained earlier as well, once Alcohol evaporates from any solution, it is only water left behind.
Most of the time, after opening the bottle or near the expiry date, Ethanol has just water with very minimal alcohol content left behind. Even if you use it, there won’t be any benefit.
How long do alcohol prep wipes last?
Are expiry alcohol wipes ok to use? Alcohol Prep wipes or prep pads come in handy for disinfecting various areas of the body. Depending on their manufacturing technology and manufacturers, they come with a 4 to 5 years shelf life.
Once the Alcohol prep wipes have expired, expect them to dry out as well. Or once the Alcohol wipes are dry, they are of no use, close to what an expiry product is. As time passes, they lose their alcohol content and their potency as well.
How to safely dispose of a bottle of expired Rubbing (Isopropyl) Alcohol?
Rubbing Alcohol is a pretty common household staple. However, once the bottle of the same goes expiry, you generally would want to get rid of it.
While throwing or flowing it away just like that can harm the environment, there are a few other disposing of ways as well.
Pour the expired bottle of Rubbing Alcohol over your sink and let it flow out. After that, let’s run cold tap water for a minute or two. If you have a garbage disposer attached to your sink, then make sure it is safe to take Isopropyl.
Note: It is advisable to only dispose of a small amount of Rubbing Alcohol in your home sink. If it is high in quantity, avoid draining it down the sink.
Check online or offline and ensure whether there is any chemical disposal center near you. If yes, you can give them the expiry Alcohol bottle for disposing of further.
Some local/ regional government allows their residents to throw solutions like Isopropyl and Ethanol in the trash.
If you happen to fall in one such region, you can also simply throw it with your other house waste.
However, consider throwing the bottle separately and nicely sealed. It will help the cleaning department easier to decompose it.
For Further Reading
- Why do we have different percentages of isopropyl alcohol?
- Benefits of Rubbing Alcohol on the body
Wrapping up…
Like any bottled solution, rubbing (Isopropyl) Alcohol to comes with a shelf life. You can check and get an idea of the same in the product (bottle).
However, if the bottle does not have any date mentioned and you are unsure, it is better to dispose of the liquid. Using anything that is gone wrong, especially chemicals, can cause severe harm.
Also, every time you buy a new bottle of Isopropyl alcohol, do check for the expiry date. If the bottle does not have one, refrain from buying it.
We're an affiliate! We may earn a small commission when you make a purchase from product links at no additional cost to you!