Flushing microfluidic sensor systems

An apparatus for measuring a property of a fluid sample that flows through an inlet line, comprising:

• a microfluidic flow line having a first end opposite a second end;
• an inlet valve fluidly coupled between the inlet line and the first end of the microfluidic flow line:
• an outlet valve fluidly coupled to the second end of the microfluidic flow line;
• at least one microfluidic sensor being disposed along the microfluidic flow line between the first end and the second end;
• and
• a fluid reservoir configured to store cleaning fluid, wherein the fluid reservoir is fluidly coupled to the microfluidic flow line;
• wherein the microfluidic flow line has a first configuration where the inlet valve and the outlet valve are configured in open states that allow the fluid sample to flow through the inlet valve into the microfluidic flow line and through the microfluid flow line in a first direction toward the second end and out the second end through the outlet valve, and the at least one microfluidic sensor is configured to measure at least one property of the fluid sample flowing in the first direction through the microfluidic flow line;
• and
• wherein the microfluidic flow line has a second configuration where the inlet valve is configured in its open state that allows cleaning fluid to move from the fluid reservoir into the microfluidic flow line and through the microfluidic flow line in a second direction toward the first end and through the inlet valve in order to remove unwanted contamination from the at least one microfluidic sensor.