Microfluidic biochip for blood typing based on agglutination reaction

A microfluidic biochip for blood typing based on an agglutination reaction, comprising:

• a specimen transfer microchannel provided with a specimen inlet;
• one or more reagent transfer microchannels each provided with a reagent inlet;
• one or more micromixers for mixing a specimen and a reagent, which are flowing along thereof, with each other, the micromixer being connected to downstream ends of the specimen and reagent transfer microchannels;
• a first passive microvalve for controlling a flow of the specimen and the reagent, the first passive microvalve being formed between the downstream ends of the specimen and reagent transfer microchannels and an upstream end of the micromixer;
• a reaction microchamber for inducing a reaction between the specimen and the reagent that are mixed with each other and stored therein, the reaction microchamber being connected to a downstream end of the micromixer;
• a microfilter for filtering off an agglutination body resulting from the agglutination reaction between the specimen and the reagent, the microfilter being connected to a downstream end of the microchamber;
• a second passive microvalve for controlling the specimen and the reagent that are mixed with each other to stay at the reaction microchamber, the second passive microvalve being formed between the downstream end of the microchamber and an upstream end of the microfilter;
• and
• an outlet for discharging the specimen and the reagent that are used for the blood typing, the outlet being connected to a downstream end of the microfilter,
• wherein the microfilter includes a plurality of micropillars arranged in a plurality of columns arranged at periodic intervals in a direction in which fluid flows and filter spaces formed respectively between pairs of the micropillars of adjacent columns,
• wherein each of the micropillars has a surface that is located at a downstream side with respect to the fluid flow direction and that is larger than a surface that is located at an upstream side with respect to the fluid flow direction.