Nanoparticle Capture by Spherical Polyelectrolyte Brushes and Its Grading Separation Assisted by Compressed CO₂

Abstract

Spherical polyelectrolyte brushes (SPBs) could capture some charged nanoparticles, due to the Donnan effect, that have been verified as promising carriers for nanoparticles. However, how to separate the nanoparticles and recycle the expensive polymer brushes is still an obstacle in industrial applications. Compressed carbon dioxide (CO2) could work as a “pressure trigger” to regulate the properties of mixed solvents to accomplish the separation process because of its antisolvent effect. Herein, Ag nanoparticles were in situ synthesized in the spherical poly­(acrylic acid) brushes with a polystyrene core (PS–PAA) and recovered easily by a suitable pressure of compressed CO2, while PS–PAA still remained in solution. After temperature quenching and depressurization, Ag nanoparticles could be collected with nearly 100% recovery ratio and narrow distribution. Moreover, further increased pressure could induce the aggregation of PS–PAA later, which could be employed to recycle the polymer brushes without any structure damage. This technique opens a novel and cost-effective way to enrich and separate the ionic material for industrial environmental engineering.

Selective Protein Separation Based on Charge Anisotropy by Spherical Polyelectrolyte Brushes

“…Cationic SPBs with a polystyrene (PS) core and a poly­(methacryloxyethyltrimethyl ammonium chloride) (PDMC) brush were synthesized by photoemulsion polymerization (Figures S1 and S2). , β-Lactoglobulin (BLG, M w = 18.3 kD, pI = 5.1) was purchased from Sigma-Aldrich. Bovine serum albumin (BSA, M w = 68 kD, pI = 4.9) and hemoglobin (HB, M w = 67 kD, pI = 7.1) were purchased from Shanghai Yuanye Bio-Technology Co. Ltd. Fluorescein isothiocyanate (FITC) and rhodamine B isothiocyanate (RITC) were purchased from Shanghai Macklin Biochemical Co., Ltd. NaCl, sodium phosphate (monobasic), standard sodium hydroxide (NaOH), and hydrochloric acid (HCl) were purchased from Sinopharm Chemical Reagent Co., Ltd.…”

Comprehensive demetallization of crude oil using spherical polyelectrolyte brushes with submicron polybutadiene latex as a core

“…The high alkaline environment and the resulting high ionic strength would be unfavorable to the demetallization of crude oil. However, due to the Donnan effect, 33 the further away from the core, the lower the density of the AA group. With the increase of alkalinity, although the ionic strength increases, the proportion of carboxyl groups in PAA ionized to carboxylate groups also increases, leading to the more obvious Donnan effect.…”

Tunable Protein Adsorption by Zwitterionic Spherical Poly(CBAA) Brushes Prepared via Photoemulsion Polymerization

“…SPB have aroused wide attention due to their simple size control, narrow particle size distribution, diverse brush structure, and good stability. Moreover, the photoemulsion polymerization method is an efficient and simple surface grafting approach and used to fabricate several SPB. − In previous work, however, photoemulsion polymerization was utilized to prepare SPB with a single type of charge, that is, positive charge or negative charge. Anionic spherical poly­(acrylic acid) brushes and poly­(styrenesulfonate) brushes and cationic spherical poly­(2-aminoethyl methacrylate hydrochloride) brushes were prepared by this method, and their protein adsorption behavior was investigated. ,, …”