title: Label-free microarray imaging for direct detection of DNA hybridization and single-nucleotide mismatches.
abstract: A novel method is proposed for direct detection of DNA hybridization on microarrays. Optical interferometry is used for label-free sensing of biomolecular accumulation on glass surfaces, enabling dynamic detection of interactions. Capabilities of the presented method are demonstrated by high-throughput sensing of solid-phase hybridization of oligonucleotides. Hybridization of surface immobilized probes with 20 base pair-long target oligonucleotides was detected by comparing the label-free microarray images taken before and after hybridization. Through dynamic data acquisition during denaturation by washing the sample with low ionic concentration buffer, melting of duplexes with a single-nucleotide mismatch was distinguished from perfectly matching duplexes with high confidence interval (>97%). The presented technique is simple, robust, and accurate, and eliminates the need of using labels or secondary reagents to monitor the oligonucleotide hybridization.
authors.affiliation: Department of Electrical & Computer Engineering, Boston University, Boston, MA 02215, USA.
authors.forename: Emre
authors.initials: E
authors.lastname: Ozkumur
authors.forename: Sunmin
authors.initials: S
authors.lastname: Ahn
authors.forename: Ayça
authors.initials: A
authors.lastname: Yalçin
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Lopez
authors.forename: Elif
authors.initials: E
authors.lastname: Cevik
authors.forename: Rostem J
authors.initials: RJ
authors.lastname: Irani
authors.forename: Charles
authors.initials: C
authors.lastname: DeLisi
authors.forename: Marcella
authors.initials: M
authors.lastname: Chiari
authors.forename: M Selim
authors.initials: MS
authors.lastname: Unlü
mesh_terms: D020137:Base Pair Mismatch / Q000235:genetics; D004252:DNA Mutational Analysis / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017403:In Situ Hybridization / Q000295:instrumentation*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D017354:Point Mutation / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling