One major symptom of atherosclerosis and vascular thrombosis is vascular stenosis caused by vascular lesion. Atherosclerosis has become one of the major threats to human health since it can result in severe diseases such as myocardial infarction and cerebral infarction. Therefore,it is of great significance to develop more effective ways to treat vascular stenosis diseases. The wall shear stress at severely stenosed arteries is at least one order of magnitude higher than that in healthy vessels. The significantly increased mechanical force could be used as a trigger signal for effective targeted drug delivery. Shear-responsive drug delivery systems can release their payloads under increased shear stress at the stenosed sites and have minimal side effects on the normal tissues and organs. Therefore, this natural physical trigger is an important and promising approach for targeted drug delivery to cure some cardiovascular diseases, especially vascular stenosis diseases such as atherosclerosis. Shear-responsive drug delivery systems have attracted great interests of researchers. The recent advances on shear-responsive drug delivery systems are reviewed. Various shear-responsive drug delivery systems classified on the basis of design ideas and responsive mechanisms are discussed. At last, the urgent needs, challenges and some personal perspectives of the shear-responsive drug carriers are also presented.
Contents
1 Introduction
2 Mechanism of shear-responsive drug delivery
3 Shear-responsive drug delivery systems
3.1 Aggregates of nanoparticles
3.2 Microcapsules and vesicles
3.3 RBCs-nanoparticles composite carriers
3.4 Supramolecular self-assembly hydrogels
4 Conclusion