Selective energy transfer between quantum dots and gold nanoparticles was used to simultaneously detect mutations in the epidermal growth factor receptor (EGFR) gene. We functionalized the surface of gold nanoparticles and green and red-emitting quantum dots using four different probe DNAs that were designed to be a perfect complementary to an in-frame deletion mutation in exon 19 or L858 R point mutation in exon 21 of EGFR. We found that the presence of the deletion mutation in exon 19 in target oligonucleotides caused fluorescence quenching at 525 nm due to energy transfer from green-emitting quantum dots to gold nanoparticles, whereas point mutation in exon 21 resulted in quenching at 620 nm due to energy transfer from red-emitting quantum dots to gold nanoparticles. This method could successfully be used to simultaneously detect the presence of two types of mutations in EGFR. We also defined a parameter (i.e., the extent of quenching) to quantify fluorescence quenching phenomenon. By varying the fraction of mutant type DNA in target oligonucleotides, we showed that detection sensitivity based on the extent of quenching was about 5%, which is lower than the conventional direct sequencing method.
Bibliographical noteFunding Information:
Keywords: EGFR; Energy transfer; Fluorescence quenching; Gold nanoparticles; Multiple mutation; Quantum dots Received 23 April 2012; accepted 3 June 2012. This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korean government (No. 2011-0029118, 2009-0082417, M10755020001-07N5502-00110). Address correspondence to Kangtaek Lee, Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, Republic of Korea. E-mail: email@example.com or Kyong-Ah Yoon National Cancer Center, Gyeonggi, Republic of Korea. E-mail: firstname.lastname@example.org
All Science Journal Classification (ASJC) codes
- Analytical Chemistry
- Clinical Biochemistry
- Biochemistry, medical