title: CombiMatrix_Human_1.6K_miRNA array [condensed version]
status: Public on Jul 31 2009
contact.city: Mukilteo
contact.first: Michael
contact.middle: Joseph
contact.last: Lodes
contact.email: mlodes@combimatrix.com
contact.state: WA
contact.address: 6500 Harbour Heights Pkwy, Suite 303
contact.department: Assay Development
contact.country: USA
contact.institute: CombiMatrix Corp
contact.phone: 425-493-2272
organism: Homo sapiens
description: Arrays for serum miRNA analysis were constructed with 547 human miRNA sequences obtained from the Sanger Database version 10.0 which appeared on 8/2/07.
  This array represents a condensed version of full 1.6K array.
manufacture_protocol: CombiMatrix uses a bench-top synthesizer (produced in-house) and proprietary electrochemical synthesis approaches (U.S. patents and foreign equivalents) that employ standard phosphoramidite chemistries.  CombiMatrix commercial 12K semiconductor CustomArray® microarray has 12,544 features (electrodes or spots) and is manufactured by ST Microelectronics.  There are 13 silver pads on the chip that provide connections between a controller instrument and each electrode on the array.  Each electrode is an independent transducer that can convert an electrical signal to a chemical reaction and, likewise, convert a chemical reaction on its surface into an electrical signal.  Using a serial bus (SPI), all 12,544 electrodes can be addressed individually in less than one second.  For oligonucleotide array synthesis, the semiconductor chip is coated with a porous layer and a single phosphoramidite (thymidine) is added.  An electrical current sent to an individual electrode decreases th  e proximal pH, which deprotects the thymidine and makes it react with a subsequent phosphoramidite that is introduced into the reaction chamber.  The synthesis of different DNA probes at individual electrodes is possible by repeating this process through approximately 100 cycles an array of 35-40mers.  Probes as large as 100mers can be synthesized, but best results are obtained with 35-40mers.