Enzyme activity test paper with high wet strength and anion adsorption properties fabricated from whole cationized softwood chemical fiber

• Published in: International journal of biological macromolecules 2024-07, Vol.273 (Pt 2), p.132769, Article 132769
• Main Authors: Zhang, He, Zhou, Miaofang, Jin, Huiqi, Jia, Wenchao, Li, Changgeng, Pan, Feng, Shi, Haiqiang
• Format: Article
• Language: English
• Subjects: Adsorption; ammonium chloride; Anions - chemistry; Cationic modification; cationization; Cations - chemistry; enzyme activity; Enzyme activity assay; Functional paper; liquids; PFI-beating; softwood; wet strength; Wood - chemistry; zeta potential
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2024.132769

Paper-based test film material is widely used in a variety of test instruments for different applications. The enzyme activity test paper sheet is one of the most popularly used test papers. Here we present a novel fabrication of paper-based enzyme activity test paper without cationic resin added in. The chemical pulping fibers were first beaten to different degrees (from 14.6 to 41.5°SR) with a PFI beater. After that, the fibers were modified with a cationic agent (3-chloro-2-hydroxypropyl trimethyl ammonium chloride) under the system of alkali and water solution. Finally, the test papers were made with the modified fiber by a regular paper former in lab. The results showed that beating is beneficial for the improvement of the cationization reaction which is indicated by the Zeta potential, FTIR and EDS. The main mechanisms involved are the destruction of crystalline zone, increase of free hydroxyl group and defibrillation. This hypothesis was supported by the SEM, XRD and fiber analyzer. Beating under the optimized condition, the wet strength and liquid absorbability of test paper can meet the application requirement, and the test results of enzyme activity are quite close to those of commercial test papers. [Display omitted] •PFI-beating enhanced active hydroxyl content in fiber and improved its accessibility.•Both PFI-beating and cationization increased the value of fiber surface charge.•PFI-beating cationic fiber improved paper sheet strength without auxiliary agent.•Enzyme activity test paper sheet had strong sensitivity to DNA polymerase.