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“How do you properly hold a spatula/scoopula or a Pasteur pipette?” isn’t a question I’m often asked on this blog [1], but it is something I’m a little pedantic about.

Pasteur pipettes are best gripped with the bottom three fingers of your hand, leaving the index finger and thumb free to press in the bulb.  Unlike the more natural “thumb and forefinger on the bulb” grip, this keeps the tip of the pipette almost perfectly still, giving you a lot more control over where and when the liquid will be dispensed. As the bulb is no longer supporting any weight the pipette is also harder to accidentally squeeze, a problem with the bulb-only grip.

Proper Pipette Holding - The bottom three fingers hold the bulk of the weight.

Proper spatula/scoopula technique is a little less well known, as the advantages aren’t quite as obvious. Similar to the pipette, the bottom three fingers of your hand should do most of the gripping, with the added addition of your thumb serving as an upper counterweight. Your index finger is kept free to tap the side of the spatula/scoopula, allowing gentle dispension of whatever solid is loaded.  By shifting the angle of the scoopula/spatula more or less solid will be shaken free with each tap.  With a little practice measuring solids will speed up three or four fold, as it’s now easy to sprinkle the exact amount of solid you need onto a weigh boat.

The angle of the scoopula determines drop rate [2].

The angle of the scoopula determines drop rate [2].


[1] I don’t get all that many questions, to be honest. If you’ve got something you’d like me to discuss, send me an email (brandon [dot] findlay [at] zoho [dot] com), leave a comment somewhere on Chemtips, or meet me on Twitter.

[2] Fun fact?  Holding a scoopula in one hand while photographing it with the other is extremely awkward.  Please forgive the strange angle.

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