Nanomaterial-based ‘chemical nose’ sensor withsufficient sensingspecificity isausefulanalyticaltool
for thedetectionoftoxicologicallyimportantsubstancesincomplicatedbiologicalsystems.Asensor
arraycontainingthreequaternizedmagneticnanoparticles(q-MNPs)–fluorescent polymersystemshas
been designedtoidentifyandquantifybacteria.Thebacterialcellmembranesdisrupttheq-MNP–
fluorescent polymer,generatingunique fluorescence responsearray.Theresponseintensityofthearray
is dependentonthelevelofdisplacementdeterminedbytherelativeq-MNP–fluorescent polymer
binding strengthandbacteriacells–MNP interaction.Thesecharacteristicresponsesshowahighly
repeatable bacteriacellsandcanbedifferentiatedbylineardiscriminantanalysis(LDA).Basedonthe
arrayresponsematrixfromLDA,ourapproachhasbeenusedtomeasurebacteriawithanaccuracyof
87.5%for107 cfu mL1 within 20min.CombinedwithUV–vis measurement,themethodcanbe
successfully performedtoidentifyanddetecteightdifferentpathogensampleswithanaccuracyof
96.8%. Themeasurementsystemhasapotentialforfurtherapplicationsandprovidesafacileandsimple
method fortherapidanalysisofprotein,DNA,andpathogens.