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All you need to know about Anaerobic Chambers

Substances like metalloproteins are said to be oxygen sensitive. The reason behind this is that it is for the maintenance of a reduced state of the substance, an environment that does not have the presence of oxygen is needed. Substances like these could easily react with the oxygen in the environment as they are sensitive to it.

This makes the work done in anaerobic chambers to be a careful one. You need to have prior knowledge and skills before handling such anaerobic chambers.

As per the time taken, the experiments performed in aerobic chambers occupy less time than the anaerobic ones and make use of more effort and energy. You always have to keep in mind that the samples must not come in contact with an oxygenated environment. This is also one of the reasons why a lot of time is occupied.

Here is what you should know about anaerobic chambers prior to working with them:

  • Anaerobic chambers resemble big boxes of gloves. These could be either in sets of one or two depending on the number of times to be used.
  • If not like boxes, the anaerobic chambers resemble bags of polyvinyl that are flexible.
  • For the purpose of eradicating oxygen from the chamber always keep a catalyst of palladium in the chamber.
  • There is the presence of a transfer chamber that is airlock so that the chamber’s environment inside does not change due to bringing external substances inside it.
  • A mixture of 95% of Nitrogen along with 5% of Hydrogen is present in the chamber.

All you need to know about Anaerobic Chambers

Things to remember prior to working in the transfer chamber:

  • Degas all the samples from any oxygen. You can do this by bringing the items in the transfer chamber.
  • Keep a track of all the necessary materials that are required for the experiment. This avoids any contamination in the room and lowers the number of times you will have to go in and out of the chamber. Therefore keeping the gas safe from getting wasted.
  • All the necessary samples and other equipment for the experiment are supposed to be brought a night earlier in the chamber.
  • Renew the catalyst used in case the detector for oxygen detects it and goes off.
  • Argon/Nitrogen gas is an inert gas is capable of purging the solutions. Do it 30 to 60 minutes before taking the samples into the intake chamber. Purge or degas buffers/solutions for 30 minutes to an hour with an inert gas such as argon or nitrogen before you bring them into the intake chamber.
  • In the presence of the reductant, you are free to let the protein that is stable and requires disulfide reduction do the process of incubation without oxygen. Once the incubation process is done, inside the chamber you can do the overnight dialysis of the reductant.
  • If you find that there is not enough stability of the protein for dialysis then you can use inert gases to degas it. Before the process of disulfide reduction follow it by equilibrating inside the chamber.

All you need to know about Anaerobic Chambers

Remember these inside the anaerobic chamber:

  • Avoid bringing ice cubes inside as it leads to the presence of some amount of oxygen in the chamber. A Styrofoam box can be used instead by storing ice packs in it. Storing of samples can also be done by using nitrogen in liquid form, this freezes the samples. However, you need to take care of this:
  • There is a possibility of the pressure inside the chamber to increase as the liquid nitrogen is capable of releasing nitrogen gas and filling up the chamber. It is advisable to vacuum out half the gas in the liquid nitrogen. Be careful.
  • Do not leave behind any trash.
  • Items such as beakers, tips for pipets in all sizes, tabletop centrifuges, all kinds of tubes (microcentrifuge, conical), etc. should be stocked up in the chamber so that the next experimenter can make use of it.

Conclusion:

Not every chamber for the experiment is anaerobic. Other chambers can be found around the lab. However all of them are not anaerobic. The following should not be confused with anaerobic chambers: glove boxes of oxygen animal study and tissue culture, dry boxes, and full control of humidity.

If you’ve never come across Anaerobic Workstations, they can be quite daunting. Performing experiments involving gases, seals, redox states, vacuums, regulators, and precipitating or evaporating proteins can be difficult.  However, the anaerobic chambers can last for a long time efficiently and produce some interesting research if they are well-maintained.

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The Importance of Anti-Slip Pendulum Feet

It is of course true that there are a few things in life more important that the anti-slip feet on the bottom of a Pendulum.  You could even argue that there are many things of higher priority than the components of a BS 7976-2 Pendulum.  What should be of the utmost importance to any Pendulum operator however, is the integrity of the testing process and the accuracy of data produced, and the performance of anti-slip feet is supremely important in ensuring this.  This is why Munro Instruments are now offering upgraded Pendulum feet.

Practical Considerations

The basic principle of a Pendulum test is just that, a weighted pendulum.  The pendulum swings from a point of release, striking the floor and reading the slip resistance of that floor on the overswing.  If the pendulum doesn’t come in to contact with the floor then it swings freely to give a 0PTV result.

The pendulum Tester must swing freely in an arc about a fixed point.  Whilst the Pendulum frame is sturdy, it wouldn’t be practical to physically fix the machine to the floor, so movement of the frame across the floor has the potential to alter results produced.  This is of such importance that measures to increase stability of the frame were introduced by the UK Slip Resistance Group, namely a weighted back foot and anti-slip feet.

The anti-slip feet are a crucial part of a robust testing system.  With a weighted back foot and anti-slip feet, the frame is held securely in position, preventing movement and associated variability in results.

The Importance of Anti-Slip Pendulum Feet

UK Legal & Regulatory Requirements

Regardless of the practical benefits of testing with anti-slip feet, the feet are an essential component of a regulator-preferred and UKSRG-defined test process.  In short, if you fail to use anti-slip feet, you have not complied with the requirements of testing as directed by the HSE.

With slip resistance testing being so closely associated with slip and fall legal claims, it is essential that testing is conducted in accordance with industry best practice.  If your Pendulum doesn’t feature anti-slip pads for the feet, you cannot claim to have tested to the UK-preferred standard.   If you haven’t done the test correctly, you shouldn’t expect the results to hold any water in court.

Company No: 6965050  Registered Office:  44-45 Burnt Mill, Elizabeth Way, Harlow, Essex  CM20 2HU

If you are conducting tests outside the UK, I would strongly advise that you check your local standards/requirements as it is likely anti-slip feet have been incorporated as part of the test method given their previously discussed positive impact on accuracy.

The Munro Instruments Anti-slip Feet

The improved feet replace the existing levelling screws in the Pendulum frame.  Rather than the pointed tip which previously required an anti-slip pad to sit in, the new screws feature a sturdy plate with a rubberised bottom, essentially incorporating a small anti-slip pad in to the feet themselves.

Unlike other designs there is no movement between pad and foot which could lead to movement of the frame.  The rotational fixed pivot of the Munro design rotates with adjustment of the feet, but is otherwise solid and stable, maximising accuracy and repeatability.

The new feet are backwards compatible with all Munro Pendulums, and it is simply a case of swapping out your older levelling screws with the new ones provided.  A 5 minute job with a significant impact on both the accuracy and validity of results produced by your machine.

Having been subject to extensive testing in the field, the feet have proven to remain effective on a wide range of materials and in a wide range of conditions, and remain effective even on difficult surfaces such as slopes, stairs and aggressive profiles.

Benefits to Pendulum Operators

If, like me, you have been using a workable but ‘DIY’ pad system, it is well worth an upgrade.  Whilst my experience as a Pendulum operator is unusual, I conduct testing daily on sites across the UK, one benefit of the improved Munro anti-slip feet was immediately apparent to me.  With the feet attached to the Pendulum frame, I didn’t have to remove and set up the pads 36 times for every test, a blessing both for my aging frame and the efficiency of testing.

Further benefits of the new anti-slip feet include the protection of easily damaged surfaces from the harsh points of the old feet, and the knowledge that the essential pads weren’t going to be forgotten or misplaced during a test remit.

Crucially, the improved factory-fit feet provide excellent performance, and look as if they belong.  Aesthetics shouldn’t matter in testing, but any observer is likely to be given a greater sense of confidence in the results with a setup that both looks and performs professionally.

Order your anti-slip feet today – www.munro-instruments.com