title: Microarray chip development using infrared imaging for the identification of catfish species.
abstract: Several families of catfish species are extensively aquacultured around the world; however, only those from the family Ictaluridae can be labeled as catfish in the United States. Non-Ictalurid catfish species that are marketed as "catfish" in the USA are considered misbranded. Misbranding in general has led to an increased interest in developing deoxyribonucleic acid (DNA)-based methods such as DNA barcoding, polymerase chain reaction restriction fragment length polymorphism, and DNA microarrays with fluorescence detection for the identification of fish species. In this proof-of-concept study, DNA microarrays coupled with a newly developed mid-infrared imaging detection method were applied to the identification of seven species of catfish for the first time. Species-specific DNA probes targeting three regions per species of the cytochrome c oxidase 1 (barcoding) gene were developed and printed as microarrays on glass slides. Deoxyribonucleic acid targets labeled with biotin were hybridized to their complementary probes using a strategy that allowed the selective formation of a silver layer on hybridized spots needed for detection. Using this three-probe format, the seven species were all identified correctly, even when a limited number of false positive spots were observed. Raman spectroscopy was employed to further characterize the arrays.
authors.affiliation: Office of Regulatory Science, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD 20740 USA.
authors.forename: Sara M
authors.initials: SM
authors.lastname: Handy
authors.forename: Vladimir
authors.initials: V
authors.lastname: Chizhikov
authors.forename: Betsy Jean
authors.initials: BJ
authors.lastname: Yakes
authors.forename: Stephen Z
authors.initials: SZ
authors.lastname: Paul
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Deeds
authors.forename: Magdi M
authors.initials: MM
authors.lastname: Mossoba
mesh_terms: D000818:Animals; D002397:Catfishes / Q000145:classification* / Q000235:genetics*; D004247:DNA / Q000032:analysis / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013055:Spectrophotometry, Infrared / Q000295:instrumentation*
chemical_list: D004247:DNA