To enhance the adhesion and polymerization of lipase-plasma-polymerized-ethylene (lipase-PPE) coatings deposited by aerosol-assisted atmospheric plasma deposition (AAAPPD), the effects of voltage, ceramic-dielectric thickness, and pre-coated PPE layer were investigated. In AAAPPD system, ethylene and lipase-phosphate-buffered-saline aerosol were used as precursors to polymerize ethylene and embed lipase simultaneously.The deposited lipase-PPE coatings were analyzed with FTIR, SEM, and surface profiler. The results show that increasing voltage from 3 to 4 kV and decreasing ceramic-dielectric thickness from 1 to 0.38 mm improved the coating adhesion and polymerization. Also, depositing a PPE layer with high energy prior to lipase-PPE coating enhanced adhesion. These improvements of the biomolecule-PPE coatings facilitate further bioapplications of this new biomoleculeembedding method.

This study shows that aerosol-assisted dielectric-barrier-discharge atmosphericpressure plasma deposition (AAAPPD) is a rapid and reagent-free method to entrap proteins on different substrates for biosensor fabrication, and the proteins were not damaged. AAAPPD involves depositing plasma-polymerized ethylene (ppE) with grafted hydroxyl functional groups and embedding the protein in the ppE in one step, making the protein entrapment faster than conventional methods and without using reagents. In this study, SEM and XPS show that more protein deposited near the inlet. Electrophoresis, temperature analysis, and immunostaining respectively demonstrated that the protein maintained its integrity, was unheated, and exhibited activity during AAAPPD. The immunostaining results of AAAPPD protein was close to that of covalent-bonded protein.AAAPPD also entraps protein on three different biosensor substrates. K E Y W O R D Saerosol-assisted atmospheric-pressure plasma deposition, fluorescence immunostaining, glass, PDMS, protein activity Plasma Process Polym. 2018;15:e1800001.www.plasma-polymers.com