title: Genotyping of single nucleotide polymorphisms by melting curve analysis using thin film semi-transparent heaters integrated in a lab-on-foil system.
abstract: The recent technological advances in micro/nanotechnology present new opportunities to combine microfluidics with microarray technology for the development of small, sensitive, single-use, point-of-care molecular diagnostic devices. As such, the integration of microarray and plastic microfluidic systems is an attractive low-cost alternative to glass based microarray systems. This paper presents the integration of a DNA microarray and an all-polymer microfluidic foil system with integrated thin film heaters, which demonstrate DNA analysis based on melting curve analysis (MCA). A novel micro-heater concept using semi-transparent copper heaters manufactured by roll-to-roll and lift-off on polyethylene naphthalate (PEN) foil has been developed. Using a mesh structure, heater surfaces have been realized in only one single metallization step, providing more efficient and homogenous heating characteristics than conventional meander heaters. A robust DNA microarray spotting protocol was adapted on Parylene C coated heater-foils, using co-polymer poly(DMA-NAS-MAPS) to enable covalent immobilization of DNA. The heaters were integrated in a microfluidic channel using lamination foils and MCA of the spotted DNA duplexes showed single based discrimination of mismatched over matched target DNA-probes. Finally, as a proof of principle, we perform MCA on PCR products to detect the Leu7Pro polymorphism of the neutropeptide Y related to increased risk of Type II diabetes, BMI and depression.
authors.affiliation: Fraunhofer EMFT, Hansastrasse 27d, 80686 Munich, Germany. anna.ohlander@emft.fraunhofer.de
authors.forename: Anna
authors.initials: A
authors.lastname: Ohlander
authors.forename: Caterina
authors.initials: C
authors.lastname: Zilio
authors.forename: Tobias
authors.initials: T
authors.lastname: Hammerle
authors.forename: Sergey
authors.initials: S
authors.lastname: Zelenin
authors.forename: Gerhard
authors.initials: G
authors.lastname: Klink
authors.forename: Marcella
authors.initials: M
authors.lastname: Chiari
authors.forename: Karlheinz
authors.initials: K
authors.lastname: Bock
authors.forename: Aman
authors.initials: A
authors.lastname: Russom
mesh_terms: D005838:Genotype; D056656:Lab-On-A-Chip Devices; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D009691:Nucleic Acid Denaturation; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation / Q000379:methods*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D013499:Surface Properties; D044366:Transition Temperature