title: Immunochromatographic assay for ultrasensitive detection of aflatoxin B₁ in maize by highly luminescent quantum dot beads.
abstract: Highly luminescent quantum dot beads (QBs) were synthesized by encapsulating CdSe/ZnS and used for the first time as immunochromatographic assay (ICA) signal amplification probe for ultrasensitive detection of aflatoxin B1 (AFB1) in maize. The challenges to using high brightness QBs as probes for ICA are smooth flow of QBs and nonspecific binding on nitrocellulose (NC) membrane, which are overcome by unique polymer encapsulation of quantum dots (QDs) and surface blocking method. Under optimal conditions, the QB-based ICA (QB-ICA) sensor exhibited dynamic linear detection of AFB1 in maize extract from 5 to 60 pg mL(-1), with a median inhibitory concentration (IC50) of 13.87 ± 0.16 pg mL(-1), that is significantly (39-fold) lower than those of the QD as a signal probe (IC50 = 0.54 ± 0.06 ng mL(-1)). The limit of detection (LOD) for AFB1 using QB-ICA sensor was 0.42 pg mL(-1) in maize extract, which is approximately 2 orders of magnitude better than those of previously reported gold nanoparticle based immunochromatographic assay (AuNP-ICA) and is even comparable with or better than the conventional enzyme-linked immunosorbent assay (ELISA) method. The performance and practicability of our QB-ICA sensor were validated with a commercial ELISA kit and further confirmed with liquid chromatography tandem mass spectrometry (LC-MS/MS). Given its efficient signal amplification performance, the proposed QB-ICA offers great potential for rapid, sensitive, and cost-effective quantitative detection of analytes in food safety monitoring.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University , Nanchang 330047, People's Republic of China.
authors.forename: Meiling
authors.initials: M
authors.lastname: Ren
authors.forename: Hengyi
authors.initials: H
authors.lastname: Xu
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Huang
authors.forename: Min
authors.initials: M
authors.lastname: Kuang
authors.forename: Yonghua
authors.initials: Y
authors.lastname: Xiong
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.forename: Hongyu
authors.initials: H
authors.lastname: Chen
authors.forename: Andrew
authors.initials: A
authors.lastname: Wang
mesh_terms: D016604:Aflatoxin B1 / Q000737:chemistry*; D002846:Chromatography, Affinity / Q000379:methods*; D045663:Quantum Dots; D003313:Zea mays / Q000378:metabolism*
chemical_list: D016604:Aflatoxin B1
references.citation: Biosens Bioelectron. 2014 Jun 15;56:340-4
references.pmid: 24549114
references.citation: Clin Biochem. 2011 Oct;44(14-15):1241-6
references.pmid: 21763300
references.citation: Anal Bioanal Chem. 2009 Nov;395(5):1309-16
references.pmid: 19756539
references.citation: Talanta. 2013 Mar 30;107:25-9
references.pmid: 23598187
references.citation: Clin Chim Acta. 2009 Aug;406(1-2):18-22
references.pmid: 19393638
references.citation: Meat Sci. 2010 Nov;86(3):733-7
references.pmid: 20667663
references.citation: Biosens Bioelectron. 2009 Apr 15;24(8):2483-7
references.pmid: 19200709
references.citation: J Agric Food Chem. 2012 Nov 21;60(46):11618-24
references.pmid: 23101730
references.citation: Anal Chim Acta. 2008 Sep 26;626(2):186-92
references.pmid: 18790120
references.citation: Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2012;29(3):383-91
references.pmid: 22243423
references.citation: Talanta. 2011 Mar 15;84(1):216-22
references.pmid: 21315923
references.citation: Biosens Bioelectron. 2013 Sep 15;47:361-7
references.pmid: 23603134
references.citation: Materials (Basel). 2012 Apr 13;5(4):634-643
references.pmid: 28817000
references.citation: Science. 2005 Jan 28;307(5709):538-44
references.pmid: 15681376
references.citation: Anal Chem. 2013 May 21;85(10):5120-8
references.pmid: 23614687
references.citation: Nat Methods. 2008 Sep;5(9):763-75
references.pmid: 18756197
references.citation: Biosens Bioelectron. 2011 Feb 15;26(6):2877-82
references.pmid: 21167703
references.citation: J Immunol Methods. 2012 Feb 28;376(1-2):97-107
references.pmid: 22197974
references.citation: Biosens Bioelectron. 2011 Dec 15;30(1):145-50
references.pmid: 21963096
references.citation: Talanta. 2011 Jul 15;85(1):736-42
references.pmid: 21645767
references.citation: Analyst. 2014 Feb 21;139(4):771-7
references.pmid: 24352570
references.citation: Anal Chem. 2013 Mar 5;85(5):2833-40
references.pmid: 23350906
references.citation: Biosens Bioelectron. 2013 Dec 15;50:338-44
references.pmid: 23880109
references.citation: ACS Appl Mater Interfaces. 2014 May 14;6(9):6406-14
references.pmid: 24761826
references.citation: Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2011 Feb;28(2):226-34
references.pmid: 21240699
references.citation: J Am Chem Soc. 2005 May 25;127(20):7480-8
references.pmid: 15898798
references.citation: Anal Chem. 2011 Sep 1;83(17):6778-84
references.pmid: 21793540
references.citation: Theranostics. 2014 Jan 25;4(3):307-15
references.pmid: 24505238
references.citation: Biosens Bioelectron. 2013 Nov 15;49:426-32
references.pmid: 23807236
references.citation: Anal Chem. 2011 Jun 1;83(11):4302-6
references.pmid: 21517090
references.citation: Biosens Bioelectron. 2011 Feb 15;26(6):2828-34
references.pmid: 21169009