By Dr Julia Lock
Stuart® has earned an excellent reputation with its products for reliability and user-friendly operation. Its laboratory products including colony counters, hotplates, rockers, shakers, water stills and stirrers bring high-quality performance and great value to laboratories around the world. In an interview with Neil Pomeroy, New Product Development Director, Renaud Foret, Category Manager and Dr Jayne Bates, Technical Support Manager, we explored some of the aspects of the range.
What would you say is the highlight of the range to date?
RF: The brand-new Premium Hotplate Stirrers are really at the forefront of the range and lead the way for a refresh of the brand. What is special about this product is the fact that, for the very first time, customers can use our online Cole-Parmer® Configurator to ‘imagine’ their Hotplate Stirrer, by selecting from a variety of parameters, including; model type, interface, plate surface, and colour. We then take this information and build each unit to exact standards, with the end-product being a very personal product, made for specific needs. Choice in the lab is here, and marks a refreshing turning point for the development of lab equipment. Indeed, these latest additions mean researchers have even greater control over their experiments and processes, while making their lab safer.
Neil, from an NPD perspective, what is your view on the new Premium Hotplate Stirrer?
NP: When we were designing the new Premium Hotplate Stirrers we wanted to maintain the focus of the Stuart range, which has always been provide reliable, precise equipment that meet requirements across a range of applications. The Hotplate Stirrers offer users the chance to design a unit to their specifications, which will give them exceptional levels of control. What is exciting is that our Premium Hotplate Stirrer offers full control over heating and stirring, with is full-colour TFT 7 segment display for both temperature and speed as a digital read-out, which, when combined with advanced programme functions gives you accuracy, repeatability and precision. What’s more there is a pulse feature that ensures agitation thus fully stirring and distributing heat through media with viscous properties.
Have there been any other recent additions to the Stuart range?
RF: Yes, we are very excited to have released the NEW Stuart 8500 Microcentrifuge. It is ideal for quick spin downs and is designed to be compact so that bench space can be optimised. Indeed, it has some innovative features including a dual locking lid for safety, built-in recessed rotor bowl to contain spills, and quick-release adapter to change out rotors without having to use tools!
What product type do you think is the most diverse?
RF: In terms of diversity, I would definitely say that we offer a large variety of shakers that provide the exact shaking motion that an application requires. We have the classic range of shakers that offer orbital, reciprocating, vortex, rotating, and rocking motions. Those with an orbital motion are used widely in application in molecular biology including aeration and prevention of “skin” formation. The reciprocating shakers makes a back-and-forth “sloshing” motion required for some test procedures. Many of our shakers provide both an orbital and a reciprocating motion for extra “dual-action” mixing versatility. Meanwhile, vortex shakers attain speeds up to 3200 rpm for vigorous mixing of capped vessels in applications including: general test tube mixing, biochemical assays, sample preparation, and resuspending cells after centrifugation. The rotators, on the other hand, lets you choose rotation angle and therefore the degree of “rise and fall” mixing, which is usually slow and gentle (up to 80 rpm) and is ideal for delicate samples. The rockers are also very good for gentle uniform mixing, of things like blood samples cell suspensions, solutions in test tubes, blots, and dye fixations.
We do also offer a range of speciality products, including: microplate, incubating, water bath, waving, and sieve shakers. Microplate shakers are ideal for immunoassay and research procedures and you can choose from a variety of features including easy plate removal, auto start-up, adjustable speed control, space saving designs, and remote-control units. Incubator shakers can be used to grow many types of cells including tissue cultures, bacterial cultures, and yeast. Water Bath shakers are ideal for thawing, heating, mixing and shaking samples in applications including hybridization, bacterial culturing, cell aeration and molecular biology assays. Waving shakers are used for operations involving shear sensitive fluids such as ELISA, DNA extraction, protein synthesis, and hybridization. Lastly, sieve shakers used to measure particle size as part of your research or quality control applications, because they provide uniform motion ensuring reproducible results that you cannot get from hand sieving.
Have you got any tips for using these products?
JB: It is really important to match your labware with the speed and pitch of your rocker/shaker, so that you avoid spillages. In addition, if you place a flask into a spring clamp, pull the clamp open enough to then insert the flask to increase the life of the clamp and spring, and prevent accidental damage to the flask. When using multiple vessels, ensure that they are evenly distributed on the platform for best operation and to reduce the chances of vibration, uneven wear on mechanics, and uneven shaking.
What else does the Stuart range have to offer?
RF: In addition to stirrers, heaters, and agitation products, the Stuart range also offers instruments for measuring and much more. We have simple products, such as colony counters, water stills and liquid handling devices, as well as very sophisticated products, such as the Melting Point SMP50.
What makes the SMP50 particularly good for measuring melting points?
RF: The SMP50, conforms to US Pharmacopeia (USP) and GLP requirements, and can accurately identify the melting point with its’ advanced digital image processing capability. If you are unsure of the melt temperature, use the rapid ramp mode to take a fast scan of the full temperature range. Set-up is easy and intuitive due to the Android™ menu system. You can take measurements, view results, save programs, set up user sign-ins, and download time-stamped videos and reports to a USB flash drive. Furthermore, there is a storage compartment for unused capillaries, which includes a glass cutter to open capillaries that are closed on both ends, and an area to hold three prepared sample capillaries safely away from the heat source.
Do you have any tips for using the SMP50?
JB: Yes, because the Melting Point Apparatus is used to determine the purity of a substance it is really important to ensure that there is no sample on the outside of the tube before inserting it into the apparatus. A sample should be used only once for melting point determination as some substances chemically decompose on heating. You should not heat the sample too fast; generally, 1 to 2ºC per minute is recommended. Lastly, if the melting temperature is unknown, first perform a rapid melt with a ramp of up to 20ºC/minute. Once the approximate melting point is known, a more appropriate plateau can be set, and a slower ramp rate used.
What feature is consistent across much of the Stuart range?
NP: The Stuart range of benchtop laboratory equipment is protected with BioCote®, which is a unique long-life antimicrobial additive that is applied to every possible external part of a piece of Stuart equipment, during the manufacturing process. This additive utilises an active silver ion treatment, which is chemically bound to equipment, to effectively protect Stuart products against a wide range of bacteria and fungi such as Aspergillus niger (black mould), Steptococcus faecalis, Salmonella enteritidis, Staphylococcus aureus (MRSA), Escherichia coli and Listeria monocytogenes for the useful life of the equipment. BioCote is also effective against antibiotic-resistant bacteria, including MRSA. BioCote acts by inhibiting microbial reproduction, and thus reduces the levels of the bacteria by up to 99% during an 8-hour period, helping you conform to the principles of good laboratory practice (GLP).
