Provided herein are methods and compositions of a surrogate mRNA drug product. The surrogate mRNA drug product is made up of a physical property surrogate, a visual property surrogate, and a chemical property surrogate. The surrogate mRNA drug product has at least one quantitative or qualitative property such as viscosity, turbidity, density, and surface tension that is comparable to and matches the same property of a mRNA drug product comprised of mRNA in a lipid nanoparticle (LNP). The surrogate mRNA drug product, however, does not comprise mRNA or LNP.