Noor Matthew M, Goswami Joyanta, Davis Virginia A
Department of Chemical Engineering, Auburn University, 212 Ross Hal, Auburn, Alabama 36849, United States.
ACS Omega. 2020 Jan 27;5(5):2254-2259. doi: 10.1021/acsomega.9b03387. eCollection 2020 Feb 11.
Carbon nanotube-lysozyme (LSZ) conjugates provide an attractive combination of high strength and antimicrobial activity. However, there has not been a direct comparison of the covalent and noncovalent methods for creating them. In this work, single-walled carbon nanotubes (SWNT) were functionalized with LSZ using both noncovalent adsorption and covalent attachment via -ethyl--(3-dimethylamino-propyl) carbodiimide hydrochloride--hydroxysuccinimide (EDC-NHS) chemistry. The amount of attached lysozyme, dispersion stability, and antimicrobial activity was compared. In addition, the mechanical properties of LSZ-SWNT in poly(vinyl alcohol) (PVA) composite films were investigated. Dispersions of covalently bound LSZ-SWNT had better dispersion stability. This was attributed to covalent functionalization enabling sustained SWNT dispersion at a lower LSZ/SWNT ratio. The covalently bound LSZ-SWNT also exhibited a lower initial rate of antibacterial response but were active over a longer time scale. Composite films made from LSZ-SWNT maintained similar activity as the corresponding dispersions. However, the noncovalent LSZ-SWNT films were stronger and more hydrolytically stable than those made from covalent LSZ-SWNT.
碳纳米管-溶菌酶（LSZ）缀合物兼具高强度和抗菌活性，极具吸引力。然而，尚未对制备它们的共价法和非共价法进行直接比较。在本研究中，通过非共价吸附以及利用1-乙基-3-（3-二甲基氨基丙基）碳二亚胺盐酸盐-羟基琥珀酰亚胺（EDC-NHS）化学法进行共价连接，使单壁碳纳米管（SWNT）与溶菌酶功能化。比较了溶菌酶的附着量、分散稳定性和抗菌活性。此外，还研究了溶菌酶-单壁碳纳米管在聚乙烯醇（PVA）复合膜中的力学性能。共价结合的溶菌酶-单壁碳纳米管分散体具有更好的分散稳定性。这归因于共价功能化能够在较低的溶菌酶/单壁碳纳米管比例下实现单壁碳纳米管的持续分散。共价结合的溶菌酶-单壁碳纳米管还表现出较低的初始抗菌反应速率，但在较长时间内具有活性。由溶菌酶-单壁碳纳米管制成的复合膜与相应的分散体保持相似的活性。然而，非共价溶菌酶-单壁碳纳米管膜比共价溶菌酶-单壁碳纳米管膜更强且水解稳定性更高。
