He was elected to the US National Academy of Engineering in 2010, the National Academy of Inventors in 2014, the National Academy of Medicine in 2019, the American Academy of Arts and Sciences in 2021, and the National Academy of Sciences in its class of 2024.

With more than 400 papers and 100 issued patents, Hubbell uses biomaterials and protein engineering approaches to investigate topics in regenerative medicine and immunotherapeutics. In regenerative medicine, he focuses on biomaterial matrices that mimic the extracellular matrix and on growth factor-extracellular matrix interactions, working in a variety of animal models of regenerative medicine. In immunotherapeutics, he focuses on nanomaterials in vaccines that target lymphoid-resident antigen-presenting cells, on protein engineering to modulate the tumor microenvironment and materials engineering to induce anti-tumor immunity, and on protein and materials engineering approaches to deliver antigen to the liver for inverse vaccines to induce tolerance to protein drugs, modulate allergy, and ameliorate autoimmunity.