Microfluidic electrochemical sensors are based on the immune response. Immune charge density or electrode potential and other parameters sensitive interface causes a change or cause a power solution of the active ingredient (or their related components) to generate or consume, causing the detected current or potential. The electrochemical parameters of the law of changing enable the immune proteins quantitative or qualitative detection. Since the immune protein molecules themselves are typically non-electrochemical activity, and therefore immune electrochemical sensor usually mark the electrically active substance or enzyme in the antigen or antibody molecules in solution antigen (antibody) immune response and by the immobilized antigen (antibody) the concentration of the sample antigen (antibody) after the change of the current signal, causing the electro-active substance or enzyme-catalyzed reaction of substrate reaction can be determined indirectly.

This review discusses the surface-enhanced Raman scattering (SERS) with efficiencies enhanced by as much as 10¹⁴-10¹⁵ fold as well as a SERS cross section on the order of 10^-17-10^-16 cm²/molecule. Despite the existing controversy on the origin of the enhancement, SERS effect offers new opportunities for spectroscopic detection of single molecules near or on the surface of metallic nanoparticles. There has been a considerable amount of research on explanation of the enhancement mechanism and on developing SERS labels as bio-analytics tools for either molecular multiplexed detection or bio-imaging at different levels.

With microfluidic technique emerging, cell manipulation technology combines with microfluidic become a promising tool for single-cell-level manipulation. To obtain a kind of or single pure target cell for eliminating interference of useless cells in the trial of molecular biology, genetic analysis, proteomics and single cell analysis, various cell manipulation techniques have been developed for recovery specific cells. In this review, we introduce the principles of each cell manipulation technology and overlook the latest achievements of cell manipulation technique by categorizing externally applied manipulation forces: optical, electrical, magnetic, acoustic, mechanical. We also summarize the advantages and drawbacks of each cell manipulation technique.

The microfluidic polymerase chain reaction (PCR) chips have undergone extensive development and nowadays have become an important domain of miniaturization technology application. Here, we review the advances of microfluidic PCR chips over the past years, from the first single chamber stationary PCR chip to the new SlipChip PCR. First, the three distinct types of microfluidic PCR chips are discussed, including chamber stationary PCR chips, flow-through PCR chips and convection PCR chips. Then we focus on droplet PCR chips and SlipChip PCR. Although they are at an early stage, they show the great potential for high-throughput PCR and robust chip. Finally, general discussions on integrated chips are given. The low cost, portable, high-throughout integrated PCR chips will certainly be further developed in spite of many challenges.