Patent ID: 8372660

Claim:
A quantitative analyzing method for detecting a specific analyte in a fluid sample, comprising steps of: providing a substrate having an upper surface concavely provided with at least one channel including a first area, a second area and a third area which are connected sequentially, the second and third areas having bottoms thereof formed respectively with thin absorptive nitrocellulose layers each having a hollow-matrix conformation, and the nitrocellulose layers at the bottoms of the second area and the third area being formed by pouring a nitrocellulose solution onto the bottoms of the second and third areas in a casting process that is followed by a drying process, wherein the channel has a surface roughness ranging from 3 μm to 50 μm, the nitrocellulose solution being formed by mixing a nitrocellulose powder with a solvent containing esters and ketones at a volumetric ratio of 1:9, the second area being configured for delivering the fluid sample and the third area being where the fluid sample reacts, each of the second and third areas having a width of at least 0.3 mm, the nitrocellulose layer of the second area comprising an average thickness which is smaller than that of the nitrocellulose layer of the third area, and the nitrocellulose layer of the third area being capable of absorbing a constant volume of the fluid sample; and wherein a reaction material is formed in the hollow-matrix conformation of the nitrocellulose layer of the third area; applying the fluid sample to the first area, so that the fluid sample is delivered by the second area and then to the third area; absorbing the fixed volume of the fluid sample by the nitrocellulose layer of the third area; and allowing the reaction material in the third area and the specific analyte in the fluid sample to react and produce a signal.