The distance of migration is inversely correlated with the molecular weight of the protein (small proteins move faster through the gel than large proteins do and therefore migrate further down the gel).
Shellac is the most expensive of the gel nail polishes on the market, and the bottles are half the size of the competition. The higher cost for the salon owner is one reason Truong believes other salons might not correct you if you ask for Shellac but choose a different gel polish when picking your color.
Gel Manicures: The Ugly Truth. To many a nail-polish addict, gel manicures can seem like nail nirvana. The quick-drying lacquers have a chemical component that hardens under a UV light, delivering glossy color that last for weeks without chipping or losing its sheen.