title: Potentiometric aptasensing of Listeria monocytogenes using protamine as an indicator.
abstract: Exposure to pathogens in recreational or drinking water is a serious public health concern. It is important to rapidly determine and identify trace levels of pathogens in real environmental samples. We report here on a label-free potentiometric aptasensor for rapid, sensitive, and selective detection of Listeria monocytogenes (LM), a pathogen widely distributed in the environment. An aptamer binds specifically to internalin A, a surface protein present in LM cells. The target-binding event prevents the aptamer from electrostatically interacting with protamine, which can be sensitively detected using a polycation-sensitive membrane electrode. Using this method, LM can be detected down to 10 CFU mL(-1). Coupled to an online filtration system, the bioassay has been evaluated with spiked coastal seawater samples and shows good recovery and high accuracy. This work demonstrates the possibility of developing potentiometric aptasensors for determination and identification of various bacteria in environmental samples.
authors.affiliation: Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes, YICCAS , Yantai, Shandong 264003, P. R. China.
authors.forename: Jiawang
authors.initials: J
authors.lastname: Ding
authors.forename: Jiahong
authors.initials: J
authors.lastname: Lei
authors.forename: Xia
authors.initials: X
authors.lastname: Ma
authors.forename: Jun
authors.initials: J
authors.lastname: Gong
authors.forename: Wei
authors.initials: W
authors.lastname: Qin
mesh_terms: D052157:Aptamers, Nucleotide / Q000138:chemical synthesis / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D060766:Drinking Water / Q000382:microbiology; D004566:Electrodes; D057230:Limit of Detection; D008089:Listeria monocytogenes / Q000302:isolation & purification*; D011073:Polyamines / Q000737:chemistry; D000071228:Polyelectrolytes; D011199:Potentiometry / Q000379:methods*; D011479:Protamines / Q000737:chemistry*; D011485:Protein Binding; D020033:Protein Isoforms / Q000737:chemistry; D012623:Seawater / Q000382:microbiology; D055672:Static Electricity
chemical_list: D052157:Aptamers, Nucleotide; D001426:Bacterial Proteins; D060766:Drinking Water; D011073:Polyamines; D000071228:Polyelectrolytes; D011479:Protamines; D020033:Protein Isoforms; C069761:internalin protein, Bacteria