Enzyme-powered motors self-propel through the catalysis of in situ bioavailable fuels,which makes them excellent candidates for biomedical applications.However,fundamental issues like their motion in biological fluids...Enzyme-powered motors self-propel through the catalysis of in situ bioavailable fuels,which makes them excellent candidates for biomedical applications.However,fundamental issues like their motion in biological fluids and the understanding of the propulsion mechanism are critical aspects to be tackled before a future application in biomedicine.Herein,we investigated the physicochemical effects of ionic species on the self-propulsion of urease-powered micromotors.Results showed that the presence of PBS,NaOH,NaCl,and HEPES reduced self-propulsion of urease-powered micromotors pointing towards iondependent mechanisms of motion.We studied the 3D motion of urease micromotors using digital holographic microscopy to rule out any motor-surface interaction as the cause of motion decay when salts are present in the media.In order to protect and minimize the negative effect of ionic species on micromotors’performance,we coated the motors with methoxypolyethylene glycol amine(mPEG)showing higher speed compared to noncoated motors at intermediate ionic concentrations.These results provide new insights into the mechanism of urease-powered micromotors,study the effect of ionic media,and contribute with potential solutions to mitigate the reduction of mobility of enzyme-powered micromotors.展开更多
基金The research leading to these results has received funding from the Spanish MINECO for grants CTQ2015-68879-R(MICRODIA)CTQ2015-72471-EXP(Enzwim)+8 种基金BOTSinFLUIDS(RTI2018-098164-B-I00)X.Arque thanks MINECO for the Severo Ochoa programme(SEV-2014-0425)for the PhD fellowship(PRE2018-083712)T.Patino thanks MINECO for the Juan de la Cierva fellowship(FJCI-2015-25578)the European Union’s Horizon 2020 research and innovation program,under the Marie Sklodowska-Curie Individual Fellowship(H2020-MSCA-IF-2018,DNAbots)R.Mestre thanks“la Caixa”Foundation through IBEC International PhD Programme“la Caixa”Severo Ochoa fellowships(code LCF/BQ/SO16/52270018)S.Sanchez acknowledges BBVA Foundation for the MEDIROBOTS project and the CERCA program by the Generalitat de CatalunyaR.Quidant,J.Ortega Arroyo,and B.Ciraulo acknowledge financial support from the European Research Council program under grant ERC-CoG Qnano-MECA(64790)Fundacio Privada Cellex,the CERCA program,and the Spanish Ministry of Economy and Competitiveness,under grant FIS2016-80293-Rthrough the“Severo Ochoa”Program for Centres of Excellence in R&D(SEV-2015-0522).
文摘Enzyme-powered motors self-propel through the catalysis of in situ bioavailable fuels,which makes them excellent candidates for biomedical applications.However,fundamental issues like their motion in biological fluids and the understanding of the propulsion mechanism are critical aspects to be tackled before a future application in biomedicine.Herein,we investigated the physicochemical effects of ionic species on the self-propulsion of urease-powered micromotors.Results showed that the presence of PBS,NaOH,NaCl,and HEPES reduced self-propulsion of urease-powered micromotors pointing towards iondependent mechanisms of motion.We studied the 3D motion of urease micromotors using digital holographic microscopy to rule out any motor-surface interaction as the cause of motion decay when salts are present in the media.In order to protect and minimize the negative effect of ionic species on micromotors’performance,we coated the motors with methoxypolyethylene glycol amine(mPEG)showing higher speed compared to noncoated motors at intermediate ionic concentrations.These results provide new insights into the mechanism of urease-powered micromotors,study the effect of ionic media,and contribute with potential solutions to mitigate the reduction of mobility of enzyme-powered micromotors.