Biochemists at Purdue University have demonstrated a process using a nanopolymer to better assess whether cancer drugs hit their targets, which may help reduce drug side effects.

They developed a nanopolymer that can be coated with drugs, enter cells, and be then removed to determine which proteins in the cells the drug has entered. Since they’re water-soluble, the nanopolymers also may be a better delivery system for drugs that do not dissolve in water effectively, says W. Andy Tao, an associate professor of biochemistry and analytical chemistry

The researchers used mass spectrometry to determine which proteins were present and targeted by the drug. The synthetic nanopolymer was equipped with a chemical group reactive to small beads. The beads retrieved the nanopolymer and attached proteins after the drug finished its work.

The nanopolymer’s abilities were demonstrated using human cancer cells and the cancer drug methotrexate. The nanopolymers were tracked using a fluorescent dye to show they were entering cells.

Knowing which proteins are targeted could allow drug developers to test whether new drugs target only desired proteins. Eliminating unintended protein targets could reduce the often-serious side effects associated with cancer drugs.

Ref.: W. Andy Tao et al., Identification of Drug Targets In Vitro and in Living Cells by Soluble-Nanopolymer-Based Proteomics, March 31 early edition, Angewandte Chemie International Edition