Molecular Engineering of Naphthalimide Methylcyclohexane Luminogen:Unraveling J^(*)-Aggregation Pattern and Sensing Melamine in Aqueous Media  

作　　者：Kavita Narang Parameswar Krishnan Iyer 

机构地区：[1]Department of Chemistry,Indian Institute of Technology Guwahati,Guwahati 781039,Assam [2]Centre for Nanotechnology,Indian Institute of Technology Guwahati,Guwahati 781039,Assam

出　　处：《CCS Chemistry》2024年第4期923-931,共9页中国化学会会刊（英文）

基　　金：The authors gratefully acknowledge financial grants from DST,India DST/CRG/2019/002614,Deity,India No.5(1)/2022-NANO,ICMR no.5/3/8/20/2019-ITR,DBT project no.BT/COE/34/SP28408/2018;the Max-Planck-Gesellschaft IGSTC/MPG/PG(PKI)/2011A/48.

摘　　要：Naphthalimide methylcyclohexane(NMICY)luminogen that features molecular conformation-directed aggregation-induced emission was prepared,and its pure equatorial conformer was isolated and wellcharacterized via various techniques,including single-crystal X-ray diffraction(SC-XRD)analysis.In NMICY,the methyl cyclohexane substituent adapted the most stable chair conformation,preventing intermolecularπ-πinteractions among the naphthalimide cores.Careful analysis of the self-assembly behavior indicated that an uncommon J^(*)-aggregation pattern was predominant for NMICY that exhibited∼450 nm emission in crystal as well as in the aggregated state[λmax=455 nm,фPL=23.22%,fw=99.9%in water or water-dimethylformamide mixture].NMICY self-assembled into cube-shaped 2D-nanoarchitecture as characterized by fieldemission scanning electron microscopy,atomic force microscopy,and dynamic light scattering(Zavg=143 nm,∼20 nm height)studies while also displaying unique optical properties in the aggregated state.The supramolecular self-assembly and aggregated state structure-property relationship in aqueous media of NMICY were optimized,and a facile strategy for the detection of melamine in milk and an aqueous solution of milk powder is reported with a limit of detection value of 0.184 ppm(milk)and 0.101 ppm(milk powder),achieved via the rare acceptor-excited photoinduced electron transfer mechanism.Furthermore,a smartphone-based,portable,and uncomplicated sensing platform was developed that simplifies the melamine detection process.

关 键 词：conformational isomers J^(*)-aggregation aggregation-induced emission supramolecular assembly melamine detection acceptor-excited photoinduced electron transfer mechanism 

分 类 号：O62[理学—有机化学]