Hybrid surface platform for the simultaneous detection of proteins and DNAs using a surface plasmon resonance imaging sensor.
In this work, we present a novel surface and assay for the simultaneous detection of DNA and protein analytes on a surface plasmon resonance (SPR) imaging sensor. A mixed DNA/oligo (ethylene glycol) (OEG) self-assembled monolayer (SAM) is created using a microarrayer. Thiol-modified single-stranded DNA sequences are spotted onto a gold-coated glass substrate. Backfilling with an OEG-modified alkanethiol creates a protein-resistant surface background. Antibodies conjugated to complementary single-stranded DNA sequences are immobilized on the surface through DNA hybridization. By converting only part of the DNA array into a protein array, simultaneous detections of DNA and protein analytes are possible. A model system of two cDNA sequences and two human pregnancy hormones are used to demonstrate the assay. No cross-reactivity was observed between DNA or protein analytes and nontargeted immobilized cDNA sequence or antibodies. A response from a detection of a single analyte in a mixture of protein and DNA analytes corresponds well with that of a single-analyte solution.
Ladd
Jon
J
Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, USA.
Taylor
Allen D
AD
Piliarik
Marek
M
Homola
Jiri
J
Jiang
Shaoyi
S
D000906:Antibodies / Q000737:chemistry; D006063:Chorionic Gonadotropin / Q000032:analysis / Q000737:chemistry; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D005640:Follicle Stimulating Hormone / Q000032:analysis / Q000737:chemistry; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D040081:Protein Array Analysis; D011506:Proteins / Q000032:analysis* / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*
D000906:Antibodies; D006063:Chorionic Gonadotropin; D011506:Proteins; D013438:Sulfhydryl Compounds; D005640:Follicle Stimulating Hormone; D004247:DNA