Micro-robots for drug delivery have learned to overcome biological barriers. Devices based on modified E. coli and nano erythrose are described by researchers at the American Institute of Physics in the journal APL Bioengineering.
Tiny bio-hybrid robots can move freely throughout the body and deliver medicine to a specified point – for example, to a cancerous tumor. However, the success of such devices depends on their biocompatibility – in other words, they should consist of materials in relation to which the human immune system will not show aggression.
In addition, such robots must move freely in a viscous medium and penetrate tissue cells and through other biological barriers to drug delivery. The latter are membranes that separate tissues from each other and regulate the penetration of the transfer of biologically active substances and medicinal substances, their distribution in the body.
In a new work, the researchers created microrobots based on a strain of Escherichia coli and nano erythrose, nanovesicles obtained from red blood cells by emptying cells, preserving membranes and filtering them to nanoscale sizes. These tiny carriers of red blood cells attach to the bacterial membrane due to the powerful non-covalent biological link between biotin and streptavidin.
The robot thus obtained not only swims faster than similar devices but also faces a lower response of the immune system due to the compositional features.