DNA detection using metal-enhanced fluorescence.

The development of rapid and sensitive DNA detection methods is critical for advancing diagnostic technologies. This study explores the application of metal-enhanced fluorescence (MEF) to achieve a highly efficient DNA detection system. Gold nanoparticles (AuNPs) were selected due to their ability to amplify fluorescence signals. Ethidium bromide (EB) was employed as the fluorescent dye, given its strong intercalation with DNA and significant fluorescence enhancement upon binding. This system was employed for the detection of double stranded DNA upon formation from binding of single stranded DNA with a complementary probe. To create the detection system, AuNPs were chemically modified with either lipoic acid or aryl diazonium salt to optimize their surface properties. A bench-top fluorimeter was used for detection. The optimized system demonstrated a detection limit as low as 0.4 µg mL-1 of test DNA, showcasing its potential for practical applications. This work highlights the harmony between AuNPs and EB in enhancing fluorescence signals, paving the way for the development of a rapid DNA detection kit. The proposed method offers a promising alternative to conventional techniques, combining simplicity, sensitivity, and cost-effectiveness.