High-precision chemical quantum sensing in flowing monodisperse microdroplets

Sarkar, Adrisha [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000278939566); Jones, Zachary R. [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000018725975X); Parashar, Madhur [University of California, Berkeley, CA (United States)] (ORCID:0000000207634351); Druga, Emanuel [University of California, Berkeley, CA (United States)]; Akkiraju, Amala [University of California, Berkeley, CA (United States)]; Conti, Sophie [University of California, Berkeley, CA (United States)]; Krishnamoorthi, Pranav [University of California, Berkeley, CA (United States)]; Nachuri, Srisai [University of California, Berkeley, CA (United States)]; Aman, Parker [University of California, Berkeley, CA (United States)] (ORCID:0009000800879322); Hashemi, Mohammad [University of California, Berkeley, CA (United States)]; Nunn, Nicholas [Adamas Nanotechnologies Inc., Raleigh, NC (United States)] (ORCID:0000000220212575); Torelli, Marco D. [Adamas Nanotechnologies Inc., Raleigh, NC (United States)] (ORCID:0000000276916491); Gilbert, Benjamin [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000308530826); Wilson, Kevin R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000302640872); Shenderova, Olga A. [Adamas Nanotechnologies Inc., Raleigh, NC (United States)]; Tanjore, Deepti [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]; Ajoy, Ashok [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); CIFAR Azrieli Global Scholars Program, Toronto, ON (Canada)] (ORCID:0000000332422913)

doi:10.1126/sciadv.adp4033

DOE OSTI · 2497295

High-precision chemical quantum sensing in flowing monodisperse microdroplets

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Abstract

A method is presented for high-precision chemical detection that integrates quantum sensing with droplet microfluidics. Using nanodiamonds (ND) with fluorescent nitrogen-vacancy (NV) centers as quantum sensors, rapidly flowing microdroplets containing analyte molecules are analyzed. A noise-suppressed mode of optically detected magnetic resonance is enabled by pairing controllable flow with microwave control of NV electronic spins, to detect analyte-induced signals of a few hundredths of a percent of the ND fluorescence. Using this method, paramagnetic ions in droplets are detected with low limit-of-detection using small analyte volumes, with exceptional measurement stability over >10 3 s. In addition, these droplets are used as microconfinement chambers by co-encapsulating ND quantum sensors with various analytes such as single cells, suggesting wide-ranging applications including single-cell metabolomics and real-time intracellular measurements from bioreactors. Important advances are enabled by this work, including portable chemical testing devices, amplification-free chemical assays, and chemical imaging tools for probing reactions within microenvironments.

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Sarkar, Adrisha [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000278939566), Jones, Zachary R. [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000018725975X), Parashar, Madhur [University of California, Berkeley, CA (United States)] (ORCID:0000000207634351), Druga, Emanuel [University of California, Berkeley, CA (United States)], Akkiraju, Amala [University of California, Berkeley, CA (United States)], Conti, Sophie [University of California, Berkeley, CA (United States)], Krishnamoorthi, Pranav [University of California, Berkeley, CA (United States)], Nachuri, Srisai [University of California, Berkeley, CA (United States)], Aman, Parker [University of California, Berkeley, CA (United States)] (ORCID:0009000800879322), Hashemi, Mohammad [University of California, Berkeley, CA (United States)], Nunn, Nicholas [Adamas Nanotechnologies Inc., Raleigh, NC (United States)] (ORCID:0000000220212575), Torelli, Marco D. [Adamas Nanotechnologies Inc., Raleigh, NC (United States)] (ORCID:0000000276916491), Gilbert, Benjamin [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000308530826), Wilson, Kevin R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000302640872), Shenderova, Olga A. [Adamas Nanotechnologies Inc., Raleigh, NC (United States)], Tanjore, Deepti [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)], Ajoy, Ashok [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); CIFAR Azrieli Global Scholars Program, Toronto, ON (Canada)] (ORCID:0000000332422913). 2024-12-11. High-precision chemical quantum sensing in flowing monodisperse microdroplets. https://doi.org/10.1126/sciadv.adp4033

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