Affinity capture of uropathogenic Escherichia coli using pigeon ovalbumin-bound Fe3O4@Al2O3 magnetic nanoparticles.
Escherichia coli and Staphylococcus saprophyticus are the most common causes of urinary tract infections, with 80% of these infections caused by uropathogenic E. coli. Because the P fimbriae of E. coli have specificity toward Gal(alpha1-4)Gal beta units, pigeon ovalbumin (POA), whose structure contains terminal Gal(alpha1-4)Gal beta moieties, was used as a probe for interaction with P fimbriated E. coli. The functional affinity probes for these bacteria by immobilizing POA--a phosphoprotein--onto the surface of magnetic iron oxide nanoparticles (NPs) coated with alumina (Fe3O4@Al2O3), using the phosphate units of POA as linking groups for the formation of phosphate-alumina complexes. The immobilization process occurred within 30 s when performing the reaction under microwave heating. The magnetic POA-Fe3O4@Al2O3 NPs generated using this facile approach exhibited specificity toward P fimbriated E. coli. The bacteria targeted by the affinity probes were characterized by matrix-assisted laser desorption/ionization mass spectrometry. The detection limit toward uropathogenic bacteria when using this approach was approximately 9.60 x 10(4) cfu/mL (0.5 mL).
Department of Applied Chemistry, National Chiao Tung University Hsinchu 300, Taiwan.
Jr-Chi
JC
Liu
Pei-Jane
PJ
Tsai
Yuan C
YC
Lee
Yu-Chie
YC
Chen
D000537:Aluminum Oxide / Q000737:chemistry*; D000818:Animals; D010856:Columbidae; D004926:Escherichia coli / Q000302:isolation & purification* / Q000472:pathogenicity* / Q000648:ultrastructure; D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D010047:Ovalbumin / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013210:Staphylococcus / Q000302:isolation & purification / Q000472:pathogenicity
D005290:Ferric Compounds; C000499:ferric oxide; D010047:Ovalbumin; D000537:Aluminum Oxide