Lub ntsej muag serums yog ib pawg tseem ceeb ntawm cov khoom tu tawv nqaij uas muaj cov ntsiab lus siab, kev ua haujlwm siab, thiab cov txiaj ntsig zoo heev. Lawv lub luag haujlwm tseem ceeb yog los daws cov teeb meem tshwj xeeb ntawm daim tawv nqaij. Nws yog cov kauj ruam hauv kev tu tawv nqaij niaj hnub uas koom nrog qhov siab tshaj plaws ntawm cov as-ham. Thaum xaiv cov tshuaj pleev ib ce, koj yuav tsum xaiv cov khoom lag luam nrog cov txiaj ntsig raws li koj cov kev txhawj xeeb tshwj xeeb ntawm daim tawv nqaij.
Qhov kev txiav txim dav dav ntawm daim ntawv thov yog tom qab ntxuav thiab toning, tom qab ntawd thov ib qho nyiaj tsim nyog rau lub ntsej muag. Raws li hom tshuaj pleev ib ce, pre-serum yog thawj cov khoom siv tawv nqaij siv tom qab ntxuav, txhawb kev nqus ntawm cov khoom tu tawv nqaij tom ntej.