Loop-Mediated Isothermal Amplification Integrated on Microfluidic Chips for Point-of-Care Quantitative Detection of Pathogens

This work shows that loop-mediated isothermal amplification (LAMP) of nucleic acid can be integrated in an eight-channel microfluidic chip for readout either by the naked eye (as a result of the insoluble byproduct pyrophosphate generating during LAMP amplification) or via absorbance measured by an optic sensor; we call this system micro-LAMP (mu LAMP). It is capable of analyzing target nucleic acids quantitatively with high sensitivity and specificity. The assay is straightforward in manipulation. It requires a sample volume of 0.4 mu L and is complete within 1 h. The sensitivity of the assay is comparable to standard methods, where 10 fg of DNA sample could be detected under isothermal conditions (63 degrees C). A real time quantitative mu LAMP assay using absorbance detection is possible by integration of optical fibers within the chip.