To prepare samples for elemntal analysis of sensitive compounds inside a glove box small capsules made out of tin proved to be reliable.

For the ease of taking pictures the process of how to prepare a sample is shown outside a glove box. The capsules are tiny and relatively soft. Therefore some custom tools are needed to prepare them inside a glove box.

• Two tweezers. At least one hast to be pointy and ideally bent (Figure 2(a)).
• A micro spatula. Bent it like in this picture (Figure 2(b)).
• A small paint brush (Figure 2(c)).
• A holder for the capsules (Figure 2(d)).

Use the pointy tweezer to place one capsule into the holder. The holder is just a small piece of metal or polymer with a small hole for the capsule (dimensions of the capsules: 3.5×7 mm). I also created a 3D printable model here.

Next use the bent spatula to fill your substance into your capsule (Figure 4). If the spoon head is bent correctly it will fit inside the capsule which makes the process much easier. The amount of substance should usually be around 2 mg but check with your analytical department first. To determine the weight it is best to put the container with your substance on a scale and zero it. By doing so you can know the difference on the scale if you get something out for your sample. Of course by doing it this way you need to be very careful not to spill any of your substance. Otherwise you would not know how much of the substance actually reached your capsule. If you have enough space on your scale you can also put your hold with the capsule onto it and zero it. Zeroing the capsule alone is not recommended because they are hard to handle and the chance of spilling the content or damaging the capsule is high.