All Publications


  • Achieving optical transparency in live animals with absorbing molecules. Science (New York, N.Y.) Ou, Z., Duh, Y. S., Rommelfanger, N. J., Keck, C. H., Jiang, S., Brinson, K., Zhao, S., Schmidt, E. L., Wu, X., Yang, F., Cai, B., Cui, H., Qi, W., Wu, S., Tantry, A., Roth, R., Ding, J., Chen, X., Kaltschmidt, J. A., Brongersma, M. L., Hong, G. 2024; 385 (6713): eadm6869

    Abstract

    Optical imaging plays a central role in biology and medicine but is hindered by light scattering in live tissue. We report the counterintuitive observation that strongly absorbing molecules can achieve optical transparency in live animals. We explored the physics behind this observation and found that when strongly absorbing molecules dissolve in water, they can modify the refractive index of the aqueous medium through the Kramers-Kronig relations to match that of high-index tissue components such as lipids. We have demonstrated that our straightforward approach can reversibly render a live mouse body transparent to allow visualization of a wide range of deep-seated structures and activities. This work suggests that the search for high-performance optical clearing agents should focus on strongly absorbing molecules.

    View details for DOI 10.1126/science.adm6869

    View details for PubMedID 39236186

  • Wireless deep-brain neuromodulation using photovoltaics in the second near-infrared spectrum. Device Cui, H., Zhao, S., Hong, G. 2023; 1 (4)

    Abstract

    Conventional electrical neuromodulation techniques are constrained by the need for invasive implants in neural tissues, whereas methods using optogenetic are subjected to genetic alterations and hampered by the poor tissue penetration of visible light. Photovoltaic neuromodulation using light from the second near-infrared (NIR-II) spectrum, which minimizes scattering and enhances tissue penetration, shows promise as an alternative to existing neuromodulation technologies. NIR-II light has been used in deep-tissue imaging and in deep-brain photothermal neuromodulation via nanotransducers. This Perspective will provide an overview for the underpinning mechanisms of photovoltaic neuromodulation and identify avenues for future research in materials science and bioengineering that can further advance NIR-II photovoltaic neuromodulation methods.

    View details for DOI 10.1016/j.device.2023.100113

    View details for PubMedID 37990694

  • Quantification of antibody avidities and accurate detection of SARS-CoV-2 antibodies in serum and saliva on plasmonic substrates. Nature biomedical engineering Liu, T. n., Hsiung, J. n., Zhao, S. n., Kost, J. n., Sreedhar, D. n., Hanson, C. V., Olson, K. n., Keare, D. n., Chang, S. T., Bliden, K. P., Gurbel, P. A., Tantry, U. S., Roche, J. n., Press, C. n., Boggs, J. n., Rodriguez-Soto, J. P., Montoya, J. G., Tang, M. n., Dai, H. n. 2020

    Abstract

    Accurate assays for the detection of antibodies to SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) are essential for the control of the COVID-19 (coronavirus disease 2019) pandemic. Here, we report antibody and antibody-avidity assays, relying on near-infrared-fluorescence amplification by nanostructured plasmonic gold substrates, for the simultaneous detection of antibodies to the S1 subunit of the spike protein and to the receptor binding domain of SARS-CoV-2 in human serum and saliva, and for quantifying immunoglobulin avidities against coronavirus antigens from SARS-CoV-2, SARS-CoV-1 and the common-cold viruses OC43, HKU1, NL63 and 229E. The antibody assay detected immunoglobulin M in 87% (52 of 60) COVID-19-positive serum samples collected 6 or more days after symptom onset (and the immunoglobulins M and G in all 33 samples collected at least 15 days after symptom onset), and correctly classified 456 out of the 457 COVID-19-negative serum samples tested (424 of them collected before the pandemic, including 73 that were positive for other viruses). We used the antibody-avidity assay to study antibody-maturation patterns, anamnestic responses, and cross-immunity to the common-cold coronaviruses.

    View details for DOI 10.1038/s41551-020-00642-4

    View details for PubMedID 33122853

  • Diagnosis of Zika virus infection on a nanotechnology platform. Nature medicine Zhang, B., Pinsky, B. A., Ananta, J. S., Zhao, S., Arulkumar, S., Wan, H., Sahoo, M. K., Abeynayake, J., Waggoner, J. J., Hopes, C., Tang, M., Dai, H. 2017

    Abstract

    We developed a multiplexed assay on a plasmonic-gold platform for measuring IgG and IgA antibodies and IgG avidity against both Zika virus (ZIKV) and dengue virus (DENV) infections. In contrast to IgM cross-reactivity, IgG and IgA antibodies against ZIKV nonstructural protein 1 (NS1) antigen were specific to ZIKV infection, and IgG avidity revealed recent ZIKV infection and past DENV-2 infection in patients in dengue-endemic regions. This assay could enable specific diagnosis of ZIKV infection over other flaviviral infections.

    View details for DOI 10.1038/nm.4302

    View details for PubMedID 28263312

  • Validation of IgG, IgM multiplex plasmonic gold platform in French clinical cohorts for the serodiagnosis and follow-up of Toxoplasma gondii infection. Diagnostic microbiology and infectious disease Pomares, C., Zhang, B., Arulkumar, S., Gonfrier, G., Marty, P., Zhao, S., Cheng, S., Tang, M., Dai, H., Montoya, J. G. 2017; 87 (3): 213-218

    Abstract

    We report the use of the multiplexed T. gondii IgG, IgM test on plasmonic gold (pGOLD) platform in the setting of T. gondii infection by analyzing 244 sera from Nice, France (seroconversion, chronically infected, non-infected and newborns serum samples). Results were compared with commercial tests for the detection of IgG and IgM and their overall clinical final interpretation of a complete serological profile. The IgG and IgM test results on the platform were in agreement in, respectively, 95% and 93% with the commercial kits. When comparing with the overall clinical interpretation of the serological profile, the agreement reached 99.5% and 97.7% for IgG and IgM, respectively. This innovative pGOLD platform allows detection of both IgG and IgM simultaneously with only ~1 microliter of serum. The multiplexed IgG/IgM test on pGOLD platform is a strong candidate for its use in the massive screening programs for toxoplasmosis during pregnancy.

    View details for DOI 10.1016/j.diagmicrobio.2016.09.001

    View details for PubMedID 28040304

  • Through-skull fluorescence imaging of the brain in a new near-infrared window NATURE PHOTONICS Hong, G., Diao, S., Chang, J., Antaris, A. L., Chen, C., Zhang, B., Zhao, S., Atochin, D. N., Huang, P. L., Andreasson, K. I., Kuo, C. J., Dai, H. 2014; 8 (9): 723-730

    Abstract

    To date, brain imaging has largely relied on X-ray computed tomography and magnetic resonance angiography with limited spatial resolution and long scanning times. Fluorescence-based brain imaging in the visible and traditional near-infrared regions (400-900 nm) is an alternative but currently requires craniotomy, cranial windows and skull thinning techniques, and the penetration depth is limited to 1-2 mm due to light scattering. Here, we report through-scalp and through-skull fluorescence imaging of mouse cerebral vasculature without craniotomy utilizing the intrinsic photoluminescence of single-walled carbon nanotubes in the 1.3-1.4 micrometre near-infrared window. Reduced photon scattering in this spectral region allows fluorescence imaging reaching a depth of >2 mm in mouse brain with sub-10 micrometre resolution. An imaging rate of ~5.3 frames/s allows for dynamic recording of blood perfusion in the cerebral vessels with sufficient temporal resolution, providing real-time assessment of blood flow anomaly in a mouse middle cerebral artery occlusion stroke model.

    View details for DOI 10.1038/NPHOTON.2014.166

    View details for Web of Science ID 000342600100016

    View details for PubMedCentralID PMC5026222