MXenes Raman spectroscopy aptamer bacteria detection biosensor cancer diagnosis colorimetric detection dark-field microscopy electrochemical immunosensor electrochemical sensor evanescent field biosensor field effect transistor fluorescence polarization fluorescence resonance energy transfer label-free microfluidic noninvasive second harmonic generation silicon photonics smartphone surface plasmon resonance thema EDItEUR::T Technology, Engineering, Agriculture, Industrial processes::TB Technology: general issues thema EDItEUR::T Technology, Engineering, Agriculture, Industrial processes::TB Technology: general issues::TBX History of engineering and technology thema EDItEUR::T Technology, Engineering, Agriculture, Industrial processes::TQ Environmental science, engineering and technology two-dimensional material