Abstract: An electrochemical biosensor for detection of a calprotectin antigen in a sample solution. The electrochemical biosensor includes a reference electrode, a counter electrode, and a working electrode. The working electrode includes a surface coated with an anti-calprotectin antibody that binds to the calprotectin antigen in the sample solution. The electrochemical biosensor detects the concentration of the calprotectin antigen in the sample solution based on a resistance change at the surface of the working electrode.

Abstract: Passive devices for non-invasive gastrointestinal (GI) sampling are disclosed. In some embodiments, a device includes a capsule housing containing an absorbent sampling hydrogel. The capsule may be ingested by a patient and subsequently travel through the GI tract. Once the capsule reaches a desired location in the GI tract, GI fluid may flow into the capsule through a sampling aperture of the capsule. The fluid may be absorbed by and stored within the sampling hydrogel for subsequent analysis, and the absorption of the fluid may cause the sampling hydrogel to expand within the capsule. The capsule may further include a sealing member positioned between the sampling hydrogel and the sampling aperture, and the expansion of the sampling hydrogel may press the sealing member against the sampling aperture to seal the capsule.

Abstract: A method of preparing a hydrogel for delivery of an active agent. The method includes providing an aqueous solution that includes the active agent; dispersing or dissolving a gel-forming polymer in the aqueous solution to form a polymer solution; and cross-linking the polymer in the polymer solution to form the hydrogel which encapsulates the active agent.