Saturated adsorption of lidocaine and coal tar dyes onto porous polytetrafluoroethylene

Polytetrafluoroethylene (PTFE) has excellent physical properties and has been used in a wide range of applications in various fields. Adsorption research on PTFE is essential as primary research for the further application of PTFE. We attempted to adsorb coal tar dyes and model drugs such as lidocaine onto PTFE as a guideline to search for medicines that adsorb onto PTFE. Saturation curves were obtained after analyzing the adsorption of coal tar dyes on PTFE using the Hanes–Woolf plot. In addition, we collected multiple cases of ATR-FTIR spectral changes and/or retention depending on TPM derivatives and other adsorbates. Lidocaine matched some coal tar dye for the apparent spectral changes between the adsorbed molecules and its crystalline powder. The apparent spectral changes are blue-shifted, suggesting a hydrophobic interaction between the dyes/lidocaine and porous PTFE. This work provides a promising strategy for further application of PTFE.