Femtoliter Scale Detection of an Antithyroid Drug Using Gold Nanoparticles in a Microfluidic Chip

Sensitive detection of methimazole (MMI) at the femtoliter (fL) scale has been achieved based on photo thermal lensing of gold nanoparticles (GNPs). GNPs were used because their surface plasmon resonance (SPR) have absorption in visible range. A combined glass microfluidic chip-photo thermal lens microscopy (MFC-PTLM) system with appropriate laser source was assembled for detection of MMI with GNPs. The thiol group of MMI bound to the surface of GNPs and created the core-shell form and reduced the surface plasmon resonance of GNPs as a consequence the PTLM signal of GNPs decreased following th...