Cov pawg ntawm cov tshuaj reagents tau muab faib raws li lawv cov kev siv lossis kev qhuab qhia, thiab ntau pawg tshiab tau ntxiv rau txawv teb chaws hauv lub yim caum. Lub tuam txhab German E. Merck tau muab faib ua 20 pawg thiab 88 pawg. JT Baker muaj 75 pawg thiab 124 pawg. Nrog rau txoj kev loj hlob ntawm kev tshawb fawb thiab thev naus laus zis, ntau yam ntawm cov tshuaj reagents tau dhau los ua ntau thiab ntau haiv neeg, thiab cov qauv ntawm pawg faib tau ua ntau dua thiab nthuav dav, thiab ntau yam yog serialized thiab matched.