Thrombosis, the occlusion of vasculature by blood clots, is a precursor to debilitating conditions including stroke, pulmonary embolism, and heart attack. Blood thinners such as heparin or Coumadin are used to treat thrombosis, but necessitate ongoing blood tests for precise drug dosing. Researchers from the University of North Carolina at Chapel Hill and North Carolina State University have developed and tested a self-regulating drug eluting patch that monitors the level of thrombin (a clot initiating enzyme) in the blood, and releases appropriate amounts of heparin in response.
The microneedle patch is meant to stick to the skin and its polymer tips are impregnated with heparin molecules attached to hyaluronic acid via amino acid chains. Thrombin eats at the amino acid connections between the hyaluronic acid and heparin, releasing the drug. The amount of heparin released is proportional to the quantity of thrombin that passes by the microneedles, allowing the patch to be automatically responsive to any developing clots. Because the amount of heparin can be adjusted on the patch to the needs of each patient, the patch can also be personalized during manufacturing.
The smart patch was tested in a murine model and demonstrated superior efficacy at mitigating thrombosis compared to the conventional delivery of heparin via injection. The current study provides compelling proof of principle, with additional preclinical testing on the horizon.
Study in journal Advanced Materials: Thrombin-Responsive Transcutaneous Patch for Auto-Anticoagulant Regulation…