摘要 : Instruments with single-molecule level detection capabilities can potentially benefit a wide variety offields, including medical diagnostics. However, the size, cost, and complexity of such devices have preventedtheir widespread u... 展开 Instruments with single-molecule level detection capabilities can potentially benefit a wide variety offields, including medical diagnostics. However, the size, cost, and complexity of such devices have preventedtheir widespread use outside sophisticated research laboratories. Fiber-only devices have recently been suggestedas smaller and simpler alternatives, but thus far, they have lacked the resolution and sensitivity of a full-fledgedsystem, and accurate alignment remains a critical requirement. Here we show that through-space reciprocaloptical coupling between a fiber and a microscope objective, combined with wavelength division multiplexingin optical fibers, allows a drastic reduction of the size and complexity of such an instrument while retainingits resolution. We demonstrate a 4×4×18 cm3 sized fluorescence correlation spectrometer, which requires noalignment, can analyze kinetics at the single-molecule level, and has an optical resolution similar to that of muchlarger microscope based devices. The sensitivity can also be similar in principle, though in practice it is limited bythe large background fluorescence of the commonly available optical fibers. We propose this as a portable andfield deployable single molecule device with practical diagnostic applications. 收起