Protocol abstract
Nature Protocols 2, - 2148 - 2151 (2007)
Published online: 30 August 2007 | doi:10.1038/nprot.2007.307
Subject Category: Genetic analysis
Application of cationic conjugated polymers in microarrays using label-free DNA targets
ChengJun Sun1, Brent S Gaylord1, Janice W Hong1, Bin Liu2 & Guillermo C Bazan3
Abstract
A fluorescence-based microarray technique that does not require target DNA labeling is detailed. This 'label-free' approach utilizes a cationic, water-soluble conjugated polymer PFBT (poly[9,9'-bis(6"-(N,N,N-trimethylammonium)hexyl)fluorene-co-alt-4,7-(2,1,3-benzothiadiazole) dibromide]), and neutral PNA (peptide nucleic acid) hybridization probes. DNA hybridization to immobilized PNA spots results in a change in the net charge at that particular surface. Electrostatic interactions between the cationic polymer and negatively charged DNA bind the polymer to the hybrid DNA/PNA complex. By exciting the conjugated polymer at 488 nm on a commercial microarray scanner, the presence of the target is directly indicated by the fluorescence emission of the polymer. This feature eliminates the necessity of target labeling required in traditional microarray protocols. There are five steps involved in the procedure before scanning or imaging the array: (i) slide hydration, (ii) target hybridization, (iii) post-hybridization washing, (iv) polymer application and (v) polymer washing. Each step takes 20 min to 1 h. The overall protocol requires approximately 2–3 h.
- Sirigen Inc., 5385 Hollister Ave., Suite 105, Santa Barbara, California 93111, USA.
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Singapore.
- Departments of Materials and Chemistry & Biochemistry, Center for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
Correspondence to: Brent S Gaylord1 e-mail: brent@sirigen.com
Correspondence to: Guillermo C Bazan3 e-mail: bazan@chem.ucsb.edu
nature-products
A-Z product listing
- 22 mm
22 mm LifterSlip(Fisher) - 22 mm 60 mm LifterSlip(Fisher)
- DNase- and RNase-free H2O(Invitrogen)
- Formamide(Sigma)
- Pap jars(Evergreen Scientific)
- Target DNA(IDT)
