Provided is a clot adhesion preventing agent capable of suppressing adhesion of clot to the inner wall surface of a blood collection container. The clot adhesion preventing agent according to the present invention includes a polyether compound or a silicone oil, and an amino acid.

The present invention relates to substrates and composites having dynamic, reversible micron-level luminal surface deformation including texture or geometric instabilities, e.g., surface wrinkling and folding. The surface deformation and its reversal to the original surface form or to another, different surface form, is effective to reduce or prevent surface fouling and, more particularly, in certain applications, to reduce or prevent unwanted platelet adhesion and thrombus formation. The substrates and composites include a wide variety of designs and, more particularly, biomedical-related designs, such as, synthetic vascular graft or patch designs.