@article {Pereira2016, title = {Hybrid microfluidic platform for multifactorial analysis based on electrical impedance, refractometry, optical absorption and fluorescence}, journal = {Micromachines}, volume = {7}, number = {10}, year = {2016}, note = {cited By 0}, publisher = {MDPI AG}, abstract = {This paper describes the development of a novel microfluidic platform for multifactorial analysis integrating four label-free detection methods: electrical impedance, refractometry, optical absorption and fluorescence. We present the rationale for the design and the details of the microfabrication of this multifactorial hybrid microfluidic chip. The structure of the platform consists of a three-dimensionally patterned polydimethylsiloxane top part attached to a bottom SU-8 epoxy-based negative photoresist part, where microelectrodes and optical fibers are incorporated to enable impedance and optical analysis. As a proof of concept, the chip functions have been tested and explored, enabling a diversity of applications: (i) impedance-based identification of the size of micro beads, as well as counting and distinguishing of erythrocytes by their volume or membrane properties; (ii) simultaneous determination of the refractive index and optical absorption properties of solutions; and (iii) fluorescence-based bead counting. {\textcopyright} 2016 by the authors.}, keywords = {Electric impedance, Electric impedance measurement, Electromagnetic wave absorption, Fluidic devices, Fluorescence, Impedance spectroscopy, Label free, Light absorption, Microelectrodes, Microfluidic chip, Microfluidics, Optical fibers, Optical properties, Photoresists, Refractive index, Refractometry, Silicones, Singlecell analysis}, issn = {2072666X}, doi = {10.3390/mi7100181}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84994806266\&doi=10.3390\%2fmi7100181\&partnerID=40\&md5=d1952ba57622eedbf79516637bb33e4d}, author = {Pereira, F.M.a b and Bernacka-Wojcik, I.a e and Ribeiro, R.S.R.c d and Lobato, M.T.a and Fortunato, E.a and Martins, R.a and Igreja, R.a and Jorge, P.A.S.d and {\'A}guas, H.a and Oliva, A.M.G.b} }