Commercial acetaminophen (1.00 g), ibuprofen (1.00 g), and naproxen (1.00 g) tablets were dissolved in dimethyl formamide using a 25 mL volumetric ask, respectively. The same process was repeated with a 1.00g sample of naproxen-PEG conjugate that was dissolved in dimethyl formamide. A TLC chamber was prepared with 10% ethyl acetate (v/v) in hexanes with a paper towel blotter. This was allowed to equilibrate while the TLC plates were prepared. A sample of each was taken with a capillary tube, and was spotted onto each of 3 silica TLC plates (silica gel 60 matrix, Millipore Sigma). Two beakers with watch glass covers were prepared with 5% and 10% ethyl acetate in hexanes. The plates were placed, with one in each chamber. The plate placed in the sealed and equilibrated chamber ran for 20 min. The resulting TLC plates were visualized under UV light at 254 nm.