Laboratory centrifuge: The Basics of Operation & Maintenance
We know that a centrifuge needs to be balanced, but what else can we do to help ensure your centrifuge runs efficiently and effectively for a longer time. It is extremely important to follow proper guidelines when operating a centrifuge, even a small one. Following them can prevent damage to the centrifuge and possible serious injury to you and others. It is not uncommon a centrifuge has been destroyed by an unsuspecting scientist or researcher just in it for the pellet. This article discusses and highlights the tips & tricks to keep your centrifuge alive.
Ensure your rotor is fully attached
Imagine when you check your safety belt for ten times before an insane roller coaster riding. After gently placing the rotor on the drive shaft, I always try to lift it to make sure it’s not loosely attached. A flying rotor is something that you really want to avoid as it can quickly turn into a weapon, destroying the inside of the centrifuge. Broken centrifuge = broke PI = get ready to start sterilizing and reusing gloves and pipette tips.
Use the right tube, rotor and speed
Before placing tubes in the rotor, make sure that your tube can withstand the speed you want to centrifuge at. You might also want to check if your tube can hold the solution well when spinning down. For example, plastic tubes will fall apart when there’s chloroform in the solution. The right size tube for the correct centrifuge is critical for successful centrifugation. The appropriate size tube prevents sample leakage or loss and allows for easy sample recovery. Many centrifuge manufacturers (especially multipurpose benchtop centrifuges) offer automatic rotor recognition feature. This feature detects a newly inserted rotor and automatically limits rpm or rcf to the rotor’s maximum permissible value. In other words, automatic rotor recognition prevents you from exceeding the speed than it was designed for.
Balance the centrifuge load
I know it’s obvious, but it has to be said. You CANNOT ‘balance’ your microcentrifuge tubes by assuming two centrifuge tubes with same volume are balanced, or estimate roughly by sight. You need to put them on the scale and, as a rule of thumb, balance them to within 0.1 grams. If you’re using a tube with a screw-on top, then include the tops while weighing the tube just in case the tube/cap assemblies you are using aren’t perfectly matched.
Keep your centrifuge and rotor clean
Centrifuge O-rings are the main source of protection against sample leakage, and must be lubricated regularly with an approved grease prior to installation of a new rotor or following cleaning. Centrifuge rotors are often made of steel or aluminum. They are prone to corrosion with all the washes, spills, and leaks that they go through in a lifetime. Rotors are protected from corrosion by an anodized coating. Washing the rotor is necessary, but washing with strong acids and bases and lab detergents can wear the anodized coating off, exposing the rotor to rust. Daily cleaning with a neutral cleaning agent should also include the interior portion of the centrifuge, the rotor chamber, and surfaces with electronic components, such as touchscreens and keypads.
Create a maintenance culture
Do take advantage of the free resources – the manual or user guide before centrifuging and before attempting to fix anything. Always pay close attention to noise, vibration, shaking, or grinding and stop the unit immediately if this occurs. If your institution doesn’t already have someone on staff to handle centrifuge problems, many manufacturers will send a professional to take care of it for you. Consider getting the centrifuge serviced by a qualified service technician once in a year to ensure that the unit is operating safely and properly. Keep a log book for each usage, recording the length of time, speed, temperature and maintenance schedule record. You read more about centrifuge care and maintenance to have in-depth knowledge on how to routinely taking care of the centrifuge.
Read more: How to select the right centrifuge for your application