Prepared media plate sterilization methods
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Transcript of Prepared media plate sterilization methods
In this video, I’m going to show you why…
You have some choices when it comes to…
Media Plate Sterilization Methods!
You’ll learn: Several methods of media plate
Sterilization…
How:Each sterilization technique works –
and…
Which method is commonly used in the micro lab.
How’s that sound, OK? Great!
Let’s get started…
Why Sterilize Media Plates?
Media plates are used in many different industries and sciences to grow specific types of bacteria.
In order to be sure we are culturing, or growing the type of “bug” we want, (our target organism), we use specific types of food, called agar.
Also, to be sure we do not cross
contaminate our experiment, we
want to make sure that we start
with a sterile media plate.
Sterility means the absence of all living things!
Clker.com
What Methods are used to Sterilize Media Plates?
First off: Gamma Radiation
One of the most widely used means ofsterilizing media plates is by the use ofGamma Radiation.
A high energy photon is emitted from anisotope source, (Cobalt 60), which in turn
creates an electron disruption
in products (ionization).
If it is a living cell, this kind of
disruption will cause DNA and GAMMA RAY BLAST!
other structural damage to the cells.
Photon induced molecular changes instructure result in death, destruction, andgenerally a really bad day for any receivingorganism!
Gamma RadiationThis type of sterilization is usually
reserved for larger processes,
but also for things like fruits!
Wanna build a Gamma Radiation
plant in your back yard for fun?
Here’s what they look like….
PS: You’re gonna need a really big Budget!
Second Up: Ethylene Oxide
Ethylene Oxide – EO, or EtO, is a chemical compound commonly used for sterilizing a wide variety of items, including medical instruments and
single use diagnostic tools.
Sterilization occurs through
time, humidity, temperature,
and gas concentration.
Disruption of organism reproduction is caused by DNA destruction with the Ethylene Oxide acting as an alkylating agent.
Lardbucket.org
OK …. so , why don’t weuse…Ethylene Oxide?Certain items like some pharmaceuticals or
electronic components can’t take
high temperatures, or steam heat.
Let’s see, what else…oh yeah –
ethylene oxide is very poisonous, and…
you need lots of special precautions and
bells and whistles just to use it safely.1
1(Bells and Whistles You Say? OK – more specifically : Pure EtO gas has a boiling point of 10.73 º C. at atmospheric pressure. Most of the time, it is mixed with Nitrogen or CO2. This is an explosive condition that requires the Intrinsic Safe material (ATEX) zoning, for security of staff and personnel as well as for security of the gas mixing process itself.
So… there’s some good reasons not to use it for fun and sterilization!
And Number Three on Our List:
Autoclaving to Sterilize Media plates can be sterilized via steam
autoclaving as long as they are made of glassor autoclaveable plastic.
Autoclaves kill organisms using steam heatunder pressure, over a certain period of timebased on the batch load.
Autoclaves can be dangerous
to operate, and require a skilled
technician as in all of the
previously mentioned
sterilization methods. (photo courtesy of MedicalExo.com)
Fifteen minutes at 15 PSI at 121 degrees C is acommon autoclave run configuration.
Are Your Media PlatesReally Sterile?
How do know that your media plates are sterile?
When you run a batch of
samples, analysts will run
a positive control, and a
sterile control with each
batch, or set of samples.
A positive control, is a plate that is run, or analyzed after having been inoculated with a certified and known bacteria, or target microorganism.
Usually in the US, we use bacteria strains certified from the ATCC, or American Type Culture Colony.
E. Coli on Modified m-TECc. Aquaplates, Prepared Media Plates
Sterile Controls in your
Runs A Sterile Control, is a plate that is
inoculated with sterile water or nothing, and incubated along with the rest of the batch to assure that the plates themselves are not a causal agent in any cross contamination issues that may arise.
No growth on a sterile
media plate.
And Number Four:Groovy-UV: Ultraviolet Sterilization
Although there are even more exoticmethods for sterilizing objects such asmedia plates, the last topically relevantmethod we shall talk about in thispresentation is UV, or ultravioletsterilization.
UV produces some UV-C and short waveemissions which wreak havoc with thenucleic acids in the DNA and RNA oforganisms.
Works great for disinfecting
residential water
systems as well.
(don’t look too closely – the light is harmful to your eyes!) ; - )
Now……you know about some Sterilization Techniques!
I hope this short presentation has been helpful for you.
If you’d like more information of this type,please feel free to visit us at:
http://www.aquaplates.com/report---pass-your-dmrqa.html
Grab Your FREE REPORT: How to PassYour DMRQA in Micro Every Time!
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