February 13, 2013
With sincere apologies to The Bard, this is a quandry that is often faced by many lab managers when their facilities group or a vendor informs them that a preventive maintenance procedure is being scheduled.
How do you know when the time is right to actually do such work (spend money)? Just because the manufacturer recommends that a PM be done every 6 or 12 months, is that the right thing to do? What if the instrument rarely gets used?
All too often, lab managers or those whose budgets will be tapped for PM services are in the position of ‘erring on the side of caution’ or take a break/fix approach. Spending unnecessarily is obviously not desirable, however waiting till something breaks can cost dearly. There has to be a better way.
A number of common lab instruments have PC based controllers (liquid handlers, readers, integrated systems) and many of those instruments include ‘log files’, which are used by operators to troubleshoot assays or techs to repair instruments. Savvy lab managers and OEM’s can use these logs to track actual usage as opposed to just following suggested time intervals. It requires someone to actually look up the log files (if they exist) and be able to interpret the data but unfortunately there are not a lot of alternatives.
The LabSquad (caution: gratuitous self promotion ahead) is looking for off-the-shelf monitoring solutions that can be adapted to lab use. Other industries commonly use data logging equipment to monitor temperature or humidity but machine usage (especially outside of manufacturing environments) is relatively uncommon. Additional obstacles present themselves in that not all lab instruments use a PC controller and there are not a lot of inexpensive data loggers to choose from. Not to be deterred, we are also looking at custom developed solutions that could be added to any lab instrument which would monitor usage and be inexpensive (cost less than US$100). Just to make it interesting, we would like such devices to wirelessly communicate with a host PC or tablet such that someone could simply pass by a lab like the fellow who reads your home water meter does by driving by your house to assess the usage of key instruments.
While The LabSquad makes it’s living by performing PM’s and repairs, we do strongly believe that we can help labs better spend their support budgets by investing available support funding more wisely. Some instruments (the workhorses) might need more frequent attention, while lesser used devices might have their PM’s pushed out further.
As Paloneus says in Hamlet, Act 2 Scene 2; “Though this be madness, yet there is method in it.” Let us know what you think about PM scheduling and how your lab goes about keeping your instruments ‘research ready.’
February 4, 2013
Although the patent for PCR expired back in 2006 and promised to herald in a new wave of low-cost thermal cyclers, the legal debate over Taq polymerase enzymes continues to make some manufactures nervous about the North American market. Still, the number of new thermal cyclers to hit the market over the last several years has increased dramatically. As the prices for these work horse devices drops accordingly, the justification for service contracts starts to wane. When opting for a low-cost unit with no local service support, some users may be okay with depot repair or flat-out replacement. When opting for higher quality units, many labs are going with periodic maintenance and routine performance rectification (OQ/PQ). Printed reports or recalibrations by the service tech can be incorporated into your lab’s SOP’s but if you are self maintaining, don’t forget to have the data signed off by more than one person, especially if you are doing forensic or clinical work.
Now, let me put my spin on centrifuge support (wouldn’t be a blog without the occasional pun, now would it?). Seriously, it doesn’t matter whether you have a floor mount, bench top or robot-loaded centrifuge, these devices get a lot of use and it is not uncommon to see units that ten or more years old. Motors and bearings don’t last forever so routine maintenance is critical. Additionally, you folks that leave your rotors in the centrifuge and never take them out should have big scarlet letters painted on your lab coats so you can be publicly ridiculed by the service community! Seriously, many a lab tech has pulled a muscle or two trying to loosen and remove a rotor that has permanently bonded with the spindle.
Last on the docket for this posting is microplate reader upkeep and maintenance. Truly, a wide-ranging topic (may have to post separately on this one to do it justice). The three main readers types (modes) are absorbance, fluorescence and luminescence and while some are limited to one mode, others can do more than one (multimode). Of course there are also fluorescence polarization (FP), time resolved fluorescence (HTRF), high content imagers and microfludic analyzers, but for today we will stick with the big three. All three types work on the basic principle of light measurement to detect samples within the wells of a plate. Absorbance readers use a light source, filters and a detector to measure what percentage of the source light is transmitted through the sample. Fluorescence readers are more sensitive and measure the amount of light emitted from the sample, while Luminescent readers have no light source and instead detect a chemical or biological reaction from the sample. Depending upon the specific reader, any number of factors can result in bad data but generally most failures are a combination of optical alignments (emitter, detector, filters…etc) or light source age. Just about every plate manufacturer provides N.I.S.T. traceable “test plates” that can be used to calibrate the device and a number of third-party companies also have more generic standards that can also be used. It seems patently obvious to say, but what is the point of conducting an assay if you cannot say with a high degree of certainty that your detection results are accurate? At a minimum, plate readers should be PM’d once per calendar year and that procedure should include a test report against a known standard. If your lab only has one reader and it is critical to your research, an annual service contract that includes analytical data would be a wise choice.