Microfluidics add-on technologies for single-cell analysis

Microfluidics revolutionized single-cell analysis in a way that was impossible through conventional methods. However, microfluidic is not a stand-alone technique and cannot perform cellular analysis under a single platform. The microfluidic systems must be integrated with other analytical approaches to achieve the multiplex profiling of cellular components. Here, we describe the integration of the microfluidic platforms with various analytical approaches such as mass spectrometry, fluorescence methods, polarized optical microscopy, chemiluminescence, Raman spectroscopy, and polymerase chain reaction. Each approach's recent advances, challenges, and future directions are discussed in detail. This review will potentially motivate the researcher to overcome the limitation discussed here and develop a whole-single-cell-assay microfluidic platform for future cellular investigation.