Microfluidic point-of-care assay

An integrated fluid sample test strip comprising:

• i. an inlet for receiving a series of solutions, said solutions comprising at least a fluid sample and a substrate solution, wherein the inlet comprises a retention valve for temporarily retaining each said solution to thereby reduce air flow through the retention valve;
• ii. a reaction chamber to receive the solutions from the inlet via the retention valve, the reaction chamber functionalized with one or more bioreceptors for binding to a target analyte;
• iii. a capillary pump to receive from the reaction chamber at least one of the solutions including at least the fluid sample, the capillary pump comprising at least one vent hole to allow any air to escape from the capillary pump and thereby reduce pressure in the capillary pump;
• iv. a test chamber to receive the substrate solution from the reaction chamber, the test chamber comprising a plurality of test electrodes to perform at least part of a biosensing test of the substrate solution;
• and
• v. a hydrophobic vent hole coupled to the test chamber to allow a flow of solution from the reaction chamber into the test chamber when the vent hole is unsealed and to allow a flow of solution from the reaction chamber to the capillary pump when the vent hole is sealed.