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Published on: February 28, 2015
Preparation of DNA-modified nanoparticles and preliminary study for colorimetric SNP analysis using their selective
Toshihiro Ihara1, Shojiro Tanaka, Yasushi Chikaura
1Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan. toshi@chem.kumamoto-u.ac.jp
Nucleic Acids Research
|July 16, 2004
Summary
DNA-modified nanospheres enable specific p53 gene detection. Different colored nanospheres aggregate to signal wild-type or mutant gene presence, allowing allele analysis.
Area of Science:
- Biotechnology
- Nanotechnology
- Molecular Biology
Background:
- Developing novel diagnostic tools for genetic analysis is crucial.
- Oligodeoxynucleotides (ODNs) are vital for specific gene targeting.
- Nanoparticle-based detection offers high sensitivity and specificity.
Purpose of the Study:
- To create DNA-modified nanospheres for detecting p53 gene mutations.
- To develop a colorimetric method for distinguishing wild-type from mutant p53 alleles.
- To assess the feasibility of using multi-colored nanospheres for allele analysis.
Main Methods:
- Immobilization of amino-terminated ODNs onto carboxylated polystyrene nanospheres via amido bonds.
- Preparation of three distinct colored (RGB) nanospheres, each functionalized with unique ODNs.
- Utilizing binary and ternary systems of nanospheres for colorimetric detection of p53 gene sequences.
- Employing fluorescence resonance energy transfer (FRET) to confirm nanosphere proximity.
Main Results:
- Successful immobilization of ~220 ODN molecules per 40 nm nanosphere, retaining hybridization specificity.
- Wild-type p53 gene samples formed yellow aggregates in a binary (R/G) system, while mutant samples did not.
- FRET analysis confirmed direct contact between nanospheres in aggregates with wild-type samples.
- RGB ternary systems produced specific aggregate colors for wild-type and mutant p53, and white emission when both were present.
Conclusions:
- DNA-modified nanospheres provide a specific and sensitive method for p53 gene detection.
- The color-coded nanosphere system allows for clear differentiation between wild-type and mutant alleles.
- This technique shows significant potential for allele analysis and genetic diagnostics.
