Microfluidic device to deliver a controlled amount of liquid to an analysis tool for analysis

A method to analyze a controlled amount of liquid on an analysis tool, wherein the method comprises:

• generating, by a pneumatic system, a negative pressure in a buffer tank thereby letting in a liquid into the buffer tank through a first check valve,
• generating, by the pneumatic system, a positive pressure in the buffer tank thereby injecting a controlled amount of liquid from the buffer tank onto the analysis tool, through a second check valve,
• analyzing the controlled amount of liquid on the analysis tool and processing the obtained data;
• controlling a drain valve to discharge a remaining liquid from the buffer tank after injection of the liquid onto the analysis tool.

A microfluidic device configured to deliver a controlled amount of a liquid to an analysis tool, wherein the microfluidic device comprises:

• a buffer tank configured to contain at least one of a liquid and a gas;
• a pneumatic system configured to create selectively a positive or a negative pressure in the buffer tank;
• at least one intake port to let a liquid in the buffer tank;
• at least one delivery port to inject a controlled amount of liquid from the buffer tank onto the analysis tool;
• at least one drain port with a controlled drain valve, located on the lower part of the buffer tank to discharge the liquid from the buffer tank;
• a check valve between the buffer tank and the analysis tool.