科学家制造出了一种无生物排斥、生物可降解的红细胞模拟物，它有可能改善医学成像而且可能有潜力把药物送入难以深入的人体区域。红细胞是炸面圈形状的细胞，通过血流输送氧，而且具有挤过小于它们的直径的血管的极大柔性。

Samir Mitragotri及其同事提出，他们有可能用聚乳酸-乙醇酸(PLGA)球复制这些细胞的形态与功能。这组作者缩小了这种合成颗粒的环形骨架的尺寸，用一层血红素和其他蛋白覆盖在它的上面，它们连接起来形成了一种柔软的蛋白质外壳。这组作者移除了PLGA的\"核心”，留下了具有与天然红细胞同样尺寸和柔性的炸面圈形状的结构，后者也能携带氧气。这组作者提出，这种红细胞样合成颗粒可以通过携带增强磁共振成像分辨率的颗粒从而改善医学成像，而且还可能用作药物载体。（生物谷Bioon.com）

生物谷推荐原始出处：

PNAS December 14, 2009, doi: 10.1073/pnas.0907127106

Red blood cell-mimicking synthetic biomaterial particles

Nishit Doshia,1, Alisar S. Zahra,1,2, Srijanani Bhaskarb, Joerg Lahannb,c,3 and Samir Mitragotria,3

aDepartment of Chemical Engineering, University of California, Santa Barbara, CA 93106; andDepartments of bMacromolecular Science and Engineering andcChemical Engineering and Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109

Biomaterials form the basis of current and future biomedical technologies. They are routinely used to design therapeutic carriers, such as nanoparticles, for applications in drug delivery. Current strategies for synthesizing drug delivery carriers are based either on discovery of materials or development of fabrication methods. While synthetic carriers have brought upon numerous advances in drug delivery, they fail to match the sophistication exhibited by innate biological entities. In particular, red blood cells (RBCs), the most ubiquitous cell type in the human blood, constitute highly specialized entities with unique shape, size, mechanical flexibility, and material composition, all of which are optimized for extraordinary biological performance. Inspired by this natural example, we synthesized particles that mimic the key structural and functional features of RBCs. Similar to their natural counterparts, RBC-mimicking particles described here possess the ability to carry oxygen and flow through capillaries smaller than their own diameter. Further, they can also encapsulate drugs and imaging agents. These particles provide a paradigm for the design of drug delivery and imaging carriers, because they combine the functionality of natural RBCs with the broad applicability and versatility of synthetic drug delivery particles.