RNA can be produced in vitro (cell free) using RNA polymerase and DNA with the desired sequence. Large scale biotech manufacturers produce RNA synthetically via high-throughput techniques and provide solutions of RNA spike-ins at predetermined concentration.
RNA can be produced in vitro (outside of cells) using an enzyme called RNA polymerase and a DNA template containing the desired sequence. Large-scale manufacturers produce synthetic RNA through high-throughput techniques, providing ready-to-use solutions of RNA spike-ins at predetermined concentrations.