Miniature Optical Fiber DNA Hybridization Sensor With Temperature Compensation Using a Gold Nanofilm-Coated Optical Fiber

Deoxyribonucleic acid (DNA) hybridization method is one of the most important techniques for detecting new disease genes. However, temperature cross sensitivity is ubiquitously found in the DNA hybridization process, which may cause DNA damage and even produce false positives. An optical DNA hybridization sensor with temperature compensation based on dual surface plasmon resonance (SPR) effect by using a gold nanofilm coating optical fiber was proposed and demonstrated. Two parameters of DNA and temperature detection were realized by different functional modifications of the gold nanofilm. Also, a matrix equation was employed to analyze the relationship between two variables. Lung cancer-related genes exon-20 gene fragment was successfully detected in our work. From the theoretical and experimental results, the DNA detection limit was 9 nmol/L, and the temperature sensitivity reaches −1.74 nm/°C. The designed sensor could detect DNA with low concentration and measure temperature at the same time. The proposed sensor has the potential to be applied in disease marker gene detection with temperature compensation.