Liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool  

作　　者：SANDRO C.OLIVEIRA MARIA S.SOARES BÁRBARA V.GONÇALVES ANDREIA C.M.RODRIGUES AMADEU M.V.M.SOARES RITA G.SOBRAL NUNO F.SANTOS JAN NEDOMA PEDRO L.ALMEIDA CARLOS MARQUES 

机构地区：[1]CICECO-Aveiro Institute of Materials,Physics Department,University of Aveiro,3810-193 Aveiro,Portugal [2]i3N,Physics Department,University of Aveiro,3810-193 Aveiro,Portugal [3]Associate Laboratory i4HB-Institute for Health and Bioeconomy,School of Sciences and Technology,NOVA University of Lisbon,1099-085 Lisbon,Portugal [4]CESAM-Centre for Environmental and Marine Studies and Department of Biology,University of Aveiro,3810-193 Aveiro,Portugal [5]Department of Telecommunications,VSB-Technical University of Ostrava,Ostrava 70800,Czech Republic [6]i3N-CENIMAT,School of Sciences and Technology,NOVA University of Lisbon,1099-085 Lisbon,Portugal [7]UnIRE,ISEL,Polytechnic Institute of Lisbon,1549-020 Lisbon,Portugal [8]Department of Physics,VSB-Technical University of Ostrava,Ostrava 70800,Czech Republic

出　　处：《Photonics Research》2024年第7期1564-1573,共10页光子学研究（英文版）

基　　金：OstravskáUniverzita v Ostravě(CZ.10.03.01/00/22_003/0000048);Fundacao para a Ciência e a Tecnologia(LA/P/0006/2020,UIDB/50011/2020 UIDP/50011/2020,LA/P/0037/2020,UIDB/50025/2020,UIDP/50025/2020,PTDC/EEI-EEE/0415/2021,UI/BD/153066/2022,UIDP/50017/2020+UIDB/50017/2020+LA/P/0094/2020)。

摘　　要：The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized laboratories.There is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of interest.Thus,in this work,we developed optical immunosensors for the selective detection of E.coli,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they experience.Each glass substrate was functionalized with anti-E.coli antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal molecules by using DMOAP during functionalization.The presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a monochromator.It was possible to detect E.coli in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕mL.Selectivity was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关 键 词：CRYSTAL ALIGNMENT analysis 

分 类 号：TS207.5[轻工技术与工程—食品科学] TP212[轻工技术与工程—食品科学与工程]