The present invention provides, among other things, methods of formulating nucleic acid-containing nanoparticles with an enzyme to afford efficient delivery of payload to a cell or tissue of interest via subcutaneous administration. In some embodiments, the present invention provides a process in which mRNA-loaded lipid nanoparticles are co-mixed with various amounts of hyaluronidase and administered via subcutaneous administration. The resulting payload can be efficiently delivered to the liver and other organs or tissues of a treated subject.
