A microscale sample transfer method


A microscale sample transfer methodhttps://pubs.acs.org/doi/pdf/10.1021/ed065p538by EJ Volker - ‎1988of reactions and...

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A Microscale Sample Transfer Method In the course of a synthetic procedure in the field of peptide chemistry we had to performs large number of TLC runs to follow the course of reactions and to examine the purity of the products. Additionally, small samples were frequently submitted for mass spectroscopic and NMR analysis. Each time it was necessary to transfer a quantity of material, in the range from a fraction of a milligram to several milligrams, from one small vial with a narrow neck to another similar vial. After struggling with a microspatula and losing samples to air currents and the effects of static electricity, we adopted the use of a closed-end melting point tuhe as the transferring device. The sample is picked up by gently tapping the open end of the tube in it, then material adhering to the outside of the tube is shaken off. The tube is transferred to the target container where it is emptied by tapping it vigorously against the side of the vial. In order to test the generality of the technique, 10 tubes each of aspirin, acetaminophen, phenacetin, benzoic acid, sodium chloride, sodium acetate, sodium bicarbonate, and sodium citrate were weighed in a charged and in a discharged condition. The results indicate that the amount of material retained after emptying is only 0-2% and that the amount transferred per tube can be modulated between 0.5 and 5 mg. This technique of solid sample transfer offers protection from accidental loss due to air movement and static electricity and might he useful in laboratories where small amounts of solids have to he handled. Eugene J. Volker and Debble Cook Shepherd College Shepherdstown. WV 25443

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Journal of Chemical Education