Microfluidic chips including a gutter having a trough and a ridge to facilitate loading thereof and related methods

A microfluidic chip comprising:

• a body;
• and
• a microfluidic network defined by the body, the network including:
• one or more inlet ports;
• a test volume having a length, a width, and a depth;
• one or more flow paths extending between the inlet port(s) and the test volume, wherein, along each of the flow path(s), fluid is permitted to flow from one of the inlet port(s), through at least one droplet-generating region in which a minimum cross-sectional area of the flow path increases along the flow path, and to the test volume;
• and
• a gutter disposed between a first surface of the body and a second surface of the body and along at least a portion of a periphery of the test volume such that fluid from the flow path(s) is not permitted to flow into the gutter without flowing through the test volume, wherein the gutter includes:
• a trough defining a portion of the second surface and extending away from the first surface of the body, along which the gutter has a depth that is at least 10% larger than the depth of the test volume at the periphery;
• and a ridge defining a portion of the second surface and extending toward the first surface of the body, where the ridge is disposed between the trough and the test volume, the gutter having a depth along the ridge that is less than the depth of the test volume at the periphery.