Nanosecond pulsed discharge plasma modified microporous resins for BSA adsorption

Atmospheric pressure plasma, as an emerging material modification technique, generates reactive species that increase the number of functional groups and modify the pore structures on adsorbents, significantly enhancing the adsorption performance. In this study, we modified the microporous resin XAD-2 using nanosecond pulse-excited coaxial solenoid discharge technology. We investigated the effects of different pulse peak voltages, gas components, and discharge times on the adsorption of bovine serum albumin by XAD-2. The results showed that plasma modification under air conditions significantly improved the BSA adsorption capacity of XAD-2. After 1 minute of treatment, the adsorption efficiency of the modified XAD-2 increased by 22.75% compared with that of the raw resin. The adsorption data were fitted to the pseudo - first - order, pseudo-second-order, and intraparticle diffusion kinetic models. The adsorption of BSA by the modified resin conformed more closely to the pseudo - second - order model, indicating that chemisorption was the dominant mechanism, which was attributed to the increase in surface functional groups resulting from the plasma treatment. The two-stage nature of the intraparticle diffusion model suggested that the adsorption process was controlled by both film diffusion and intrapore diffusion.