Heat-Sealer From Eppendorf

The Eppendorf microtiter plate heat sealer is a useful piece of lab equipment. It works with both foil-seals and thermoplastic, transparent sheets for real-time PCR work. The process is trivially simple, but at the same time, a little frustrating. It takes TWENTY minutes to heat up to full operating temperature, which seems strange to me, because it’s really just a cross between a sandwich toaster and a steam iron. And an expensive one at that. The twenty minute waiting time means that you have to think ahead and switch it on before you’re ready to seal. This can be slightly annoying, especially if you’re doing PCR, and have forgotten about it until after you’ve prepared your samples. I often find myself reaching for an emergency adhesive seal for this very reason.

In my experience, 96-well plates locate easily in the baseplate, and the sealing process take 3-5 seconds at the most. The baseplate is interchangeable to fit 384-well microtiter plates if required. This makes it more cost effective for those who use both plate formats. Having said that, it does mean some additional expense, as the sealer is supplied with just one of the plates. The actual machine is conveniently small, and only occupies a tiny corner of a lab. It is unnecessarily heavy, but still very portable.

Eppendorf purport that the heat sealer is suitable for plates of differing heights. This is certainly true, but it can hardly be called a feature. There is no easy way to control how hard to press the heater down, so early attempts resulted in melted or deformed plates. However, after a few uses, this becomes straightforward. Eppendorf also claim that the device has a thermostat, which prevents over-heating. Again, this is true, but is of no consequence since the user must decide (or guess) how long to hold the heating block down, and this alone determines how hot the microtiter plate gets.

With foil seals and plastic sheets, I find that plates are sealed effectively. I do not see evaporation from any of my samples, so it’s certainly good for PCR or other thermocycling work. Correspondingly, it also gives a good air-tight seal, for users who want to prevent ingress of moisture into their plates.

On the whole, I’d say this is a good piece of equipment, but it is highly over-priced. It definitely does not feel like good value for money. It is reassuringly robust though, and will probably still be working well in twenty years time. So, in that context, perhaps it is a good investment for your laboratory.