Platelets identical to natural
Artificial platelets have been created
Nanonewsnet based on UCSB materials: UC Santa Barbara Researchers Develop Synthetic PlateletsScientists from the University of California at Santa Barbara (University of California - Santa Barbara, UCSB) in collaboration with their colleagues from the Scripps Research Institute and the Sanford-Burnham Medical Research Institute in La Jolla (all USA) have created artificial platelets.
An article about their work was published in the journal Advanced Materials (Doshi et al., Platelet Mimetic Particles for Targeting Thrombi in Flowing Blood).
Platelets are cellular components of blood that prevent severe bleeding and take an active part in the healing process of wounds. The fulfillment of these complex biological tasks is possible due to the unique physical and biochemical properties of these cells. The size of discoid flexible platelets is only 2-4 microns (for comparison, it is smaller than the size of red blood cells – erythrocytes).
"After further improvement and comprehensive testing, synthetic platelets can be used in various fields of biomedicine," comments its author Nishit Doshi, a researcher at the Department of Chemical Engineering, on the prospects of his development.
The problem Doshi and his colleagues had to solve was to develop a particle of a size comparable to a real platelet – with a diameter of about 1/50 of the diameter of a hair – with the key structural properties of this cell.
Polymer particles are a particularly attractive material that allows simulating the size, shape and surface functionality of natural platelets. However, their rigidity is several orders of magnitude higher than that of living cells.
To solve the problem of flexibility, UCSB scientists used a polymer "template" – a core with layers of proteins and polyelectrolytes applied to it and stitched together. This makes it possible to obtain a stable synthetic particle in the form of a platelet. The rigid polymer core is then dissolved, and the particle acquires the necessary degree of flexibility. But it still needs to be "equipped" with proteins located on the surface of natural activated platelets or damaged blood vessels – this procedure is performed by scientists from the Scripps Institute.
Artistic representation of artificial platelets and erythrocytes and their natural analogues. (Peter Allen)
Such synthetic platelets can be used not only to perform the usual functions of human platelets, but also to transport contrast agents that help find damaged blood vessels, or to deliver drugs that dissolve blood clots.
Although blood clotting factors and donor platelets are widely used to stop bleeding, immune reactions and the risk of blood clots remain serious problems in this area. The version of synthetic platelets developed at UCSB represents the latest and one of the most successful attempts to simulate the functions of platelets made in recent years.
"This development is an important milestone in the field of biomimetic materials," says Professor of chemical Engineering Samir Mitragotri, director of the Center for Bioengineering (UC Santa Barbara's Center for Bioengineering), one of the authors of the article. "Our capabilities in the construction of materials and knowledge in the field of platelet biology of scientists from the laboratory of Professor Ruggeri (Ruggeri) allowed us to obtain synthetic platelets that combine the unique physical and biological properties of natural ones."
Research in the field of biomaterials is one of the main activities of the UCSB Bioengineering Center. In 2009, Doshi and his colleagues from the laboratory of Professor Mitragotri developed synthetic red blood cells.
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