Cellulose Acetate/P4VP-b-PEO Membranes for the Adsorption of Electron-Deficient Pharmaceutical Compounds

Abstract

The prevalence of pharmaceutical compounds in surface and groundwater presents a rising threat to human health. As such, the search for novel materials that serve to avoid their release into the environment or for the remediation once in the water effluent is of utmost importance. The present work describes the fabrication of a cellulose acetate membrane modified with the block copolymer poly(4-vinylpyridine-b-ethylene oxide) (P4VP-b-PEO) crafted for the specific targeting and adsorption of electron-deficient pharmaceuticals (EDPs). The EDPs under study were sulfamethoxazole, sulfadiazine, and omeprazole. The results as part of this work present a thorough characterization of the prepared membranes by FTIR, contact angle measurement, and SEM images. Moreover, results show that the adsorptive character of the membrane correlates with the relative electron deficiency and spatial orientation of the contaminant. Interestingly, the addition of nominal 1% P4VP-b-PEO to the cellulose matrix helps to increase the adsorption efficiency of the membranes by at least 2-fold in most cases. For the compounds studied, the prepared membrane has a higher efficiency toward omeprazole followed by sulfamethoxazole and sulfadiazine. This work may serve to inspire the design and fabrication of selective soft materials for the adsorption and remediation of contaminants of emerging concern.

Porous Cellulose Acetate/Block Copolymer Membranes for the Recovery of Polyphenolic Compounds from Aquatic Environments

“…It has been established that the PEO-b-P4VP is able to adsorb pharmaceutical compounds through electron donor−acceptor or π-π interactions. 21,22 Additionally, PEO-b-P4VP can interact with water molecules through hydrogen bonding, thus maintaining a hydrophilic character. Furthermore, the interaction between PEO and polyphenols has been widely studied and hydrogen bonds have been identified as the main mechanism of interaction.…”

“…Recent publications have reported the interaction of the diblock copolymer (DiBCP) poly­(ethylene oxide- b -4-vinylpyridine) (PEO- b -P4VP) with different emerging contaminants present in water. It has been established that the PEO- b -P4VP is able to adsorb pharmaceutical compounds through electron donor–acceptor or π-π interactions. , Additionally, PEO- b -P4VP can interact with water molecules through hydrogen bonding, thus maintaining a hydrophilic character. Furthermore, the interaction between PEO and polyphenols has been widely studied and hydrogen bonds have been identified as the main mechanism of interaction. , Previous reports have proposed that the P4VP monomer on the block copolymer interacts with hydroxyl groups in surfaces, leaving PEO, the hydrophilic monomer, exposed and able to interact with the polyphenol through hydrogen bonding. , …”

Novel PVDF-PEG-CaCO3 Membranes to Achieve the Objectives of the Water Circular Economy by Removing Pharmaceuticals from the Aquatic Environment

“…The membranes obtained in this work are characterised by better adsorption properties and a higher permeability value than membranes made of Cellulose Acetate/P4VP-b-PEO and presented in [ 42 ]. Comparing the results of our paper with the results of papers [ 43 , 44 ] concerning the integrated ultrafiltration-photocatalysis process, it can be concluded that the degree of sulfadiazine removal is comparable for both methods with similar permeability values.…”

Cellulose acetate-based membrane for wastewater treatment—A state-of-the-art review

“…Laura et al fabricated a cellulose acetate-based membrane modified with block co-polymer poly(4-vinylpyridine- b -ethylene oxide) (P4VP- b -PEO) for the adsorption of several electron-deficient EDPs. 189 This study showed that the adsorption behavior of the membrane is directly relevant to the electron deficiency and spatial orientation of the contaminants. Moreover, the incorporation of 1% P4VP- b -PEO into the CA membrane significantly enhances the adsorption efficacy by at least 2-fold.…”

“…In case of CA-based membrane, negative functional groups such as hydroxyl and carboxylic groups are predominant, which can adsorb positively-charged pharmaceuticals. 189,190 Removal by the charge repulsion mechanism arises when the charge of the membrane surface and the ions of the electrolyte in pharmaceutical and personal care products (PPCPs) are similar and prevent the ion from contacting the membrane. 187 In the sieving mechanism, pollutants are separated by molecular size if molecules are larger than the membrane pores that cannot pass through the membrane.…”