绿光森林

科学家开发新技术可以大规模生产生物降解微型机器人_我的网站

新白娘子传奇

A | 为了创造一种每分钟可以生产100多个可在体内分解的微机器人技术，大邱庆北科技学院（DGIST）机器人和机电工程系的Hongsoo Choi教授团队与韩国天主教大学首尔圣玛丽医院的Sung-Won Kim教授团队以及苏黎世联邦理工学院的Bradley J. Nelson教授团队合作。

B | ANN ARBOR, Mich. -- Greg Schneider scans rows upon rows of liquid-filled glass jars containing coiled snake specimens, just a portion of the University of Michigan Museum of Zoology's reptile and amphibian collection believed to be the largest held by any research institution in the U.S. thanks to a recent donation. The museum this fall acquired tens of thousands of reptile and amphibian specimens from Oregon State University, many of which are snakes. The development places the university in a unique position, according to Schneider, the research museum collections manager for the museum's division of reptiles and amphibians.“I’m fairly confident we’ll have the largest snake collection in the world,” he said. The extensive new additions also will allow scientists to conduct new snake and amphibian research, perhaps looking at trait evolution in mothers and their offspring. Numerous studies have been conducted in recent years about declining amphibian and reptile populations, Schneider said, noting they “are very good biological indicators of the health of the environment and ecosystems,” especially the amphibians.“Amphibians, unlike people, breathe at least partly through their skin, which is constantly exposed to everything in their environment,” he said, adding that “the worldwide occurrences of amphibian declines and deformities could be an early warning that some of our ecosystems, even seemingly pristine ones, are seriously out of balance.”Boxes containing water snakes, garter snakes, woodland salamanders, dusky salamanders and other species arrived last month. They were euthanized and ultimately placed in a solution that is 75% ethanol. The donations represent the lifetime work of two retired Oregon State professors, Lynne Houck and Stevan Arnold, who received a doctorate from Michigan in 1972.Schneider has yet to complete the painstaking process of cataloging the new material, but estimates it contains around 30,000 snakes. He said that would give Michigan a total of between 65,000 to 70,000 of the slithering vertebrates, surpassing collections at the Smithsonian in Washington, the American Museum of Natural History in New York and the University of Kansas. Some of the specimens housed at the museum prior to the Oregon State donation predate the Civil War.The "largest snake collection" title would be nice, but Schneider said the true promise of a big collection is new research opportunities. “The more stuff you have and the more associated materials that you have, the more things you can do,” Schneider said.The newly acquired Oregon State collection also includes about 30,000 associated frozen tissue samples. Along with advances in molecular genetics and more sophisticated DNA analyses, the samples will allow research that could result in a better understanding of inheritance, evolutionary relationships and “has huge applications in medicine,” said Hernán López-Fernández, an associate professor in Michigan's Department of Ecology and Evolutionary Biology.A number of the newly acquired jars contain both snakes and litters of their newborns, which Michigan professor Dan Rabosky said “is very, very rare for museum collections and is incredibly powerful for research, because it lets researchers ask questions about genetics that would otherwise not be possible.” Despite the daunting task of organizing the new collection, Schneider said he and his colleagues have noticed renewed excitement in team members who staff the university’s 153,375-square-foot (14,249-square-meter) Research Museums Center, where the specimens are housed.“Since these specimens arrived, people are very, very, very enthusiastic and supportive,” Schneider said. “And excited about the kinds of research that are going to be done with these collections.”。
以微创靶向精准治疗为目标，构建微型机器人的方法有很多。其中最受欢迎的是被称为双光子聚合法的超精细3D打印工艺，它通过两个激光器相交引发合成树脂的聚合。这种技术有能力创建具有纳米级精度的结构。缺点是创建一个微型机器人需要大量的时间，因为体素，即通过3D打印实现的像素，必须连续固化。此外，在双光子聚合过程中，机器人中的磁性纳米粒子可能会阻碍光路。当利用高浓度的磁性纳米粒子时，过程结果可能不均匀。

C | 为了解决目前微机器人生产技术的限制，DGIST教授Hongsoo Choi的研究团队创造了一种方法，通过将磁性纳米颗粒和可生物降解的甲基丙烯酸明胶的混合物流到微流控芯片上，以每分钟100个的高速度制造微机器人，该混合物可以通过光固化。与现有的双光子聚合方法相比，这可以使制造微型机器人的速度提高1万倍以上。然后，用这种技术生产的微型机器人与从人的鼻子中收集的人类鼻甲骨干细胞进行培养，以诱导干细胞粘附到微型机器人的表面。通过这一过程，制造了一个干细胞携带的微型机器人，包括内部的磁性纳米颗粒和附着在外表面的干细胞。当机器人内部的磁性纳米粒子对外部磁场作出反应时，机器人就会移动，并能移动到所需的位置。
在现有的干细胞疗法中，选择性的细胞输送是困难的。

D | 然而，携带干细胞的微型机器人可以通过实时控制电磁场控制系统产生的磁场而移动到所需的位置。研究小组进行了一项实验，检查携带干细胞的微型机器人是否能通过一个迷宫状的微通道到达目标点，并因此证实机器人可以移动到所需的位置。此外，通过将携带微型机器人的干细胞与一种降解酶进行孵化，评估了微型机器人的可降解性。孵化6小时后，微机器人完全解体，机器人内部的磁性纳米粒子被磁场控制系统产生的磁场收集。