An experiment was developed to demonstrate a microfluidic device in the analytical chemistry (instrumental analysis) laboratory. Students made the paper-based microfluidic device with a wax pen and a piece of filter paper and used it to determine the total quantity of amino acids in a green tea leaf extract. The device is low cost, easy-to-make, and easy-to-use. The student results compared favorably with those from standard method. (Contains 2 figures.)