title: Development and application of a sensitive, rapid, and reliable immunomagnetic separation-PCR detection method for Cronobacter spp.
abstract: Cronobacter spp. have been linked to clinical cases of infection in both adults and infants. Enrichment of Cronobacter spp. before detection has been necessary but is quite time consuming. Hence, we sought to develop an immunomagnetic separation (IMS) PCR method that could shorten the time of enrichment before the detection of Cronobacter spp. The polyclonal antibody used in this immunomagnetic separation was prepared based on the outer membrane protein A of Cronobacter sakazakii China Center of Industrial Culture Collection 21560 and had high specificity to the target. The primers used in the IMS-PCR method also showed high specificity. The detection limit of IMS-PCR for pure C. sakazakii culture was 5.2 × 102cfu/mL. Cronobacter sakazakii in artificially contaminated powdered infant formula (PIF) was also detected at a detection limit of 5.2 × 102cfu/mL. After 8 h of enrichment, the detection limit in PIF was lower than 5.2 × 101cfu/mL. An interference test using Escherichia coli in artificially contaminated PIF showed that the IMS-PCR method developed in this study had a good ability to resist interference. Finally, the IMS-PCR method was applied to the detection of Cronobacter in food samples and was shown to be reliable. Thus, this newly developed IMS-PCR detection method was quite sensitive, rapid, and reliable and could be applied to the detection of Cronobacter in foods.
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, People's Republic of China.
authors.forename: Qiming
authors.initials: Q
authors.lastname: Chen
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, People's Republic of China; Department of Public Health, Xuzhou Medical College, 209 Tongshan Road, Xuzhou, Jiangsu 221004, People's Republic of China.
authors.forename: Yuanhong
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, People's Republic of China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Tao
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, People's Republic of China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Bie
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, People's Republic of China.
authors.forename: Fengxia
authors.initials: F
authors.lastname: Lu
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, 1 Weigang, Nanjing 210095, People's Republic of China. Electronic address: fmb@njau.edu.cn.
authors.forename: Zhaoxin
authors.initials: Z
authors.lastname: Lu
mesh_terms: D000818:Animals; D059126:Cronobacter / Q000235:genetics*; D044083:Cronobacter sakazakii / Q000235:genetics; D005506:Food Contamination; D005516:Food Microbiology; D006801:Humans; D018189:Immunomagnetic Separation; D007223:Infant; D041943:Infant Formula; D016133:Polymerase Chain Reaction
keywords: Cronobacter spp.; PCR; immunomagnetic separation; polyclonal antibody