Bio

I am a PhD graduate student and a Stanford ChEM-H Chemistry/Biology Interface Predoctoral Trainee at Stanford University, Department of Chemistry under the supervision of D.H. Chen Professor of Bioengineering Karl Deisseroth. I am interested in developing new chemical/protein tools to study neuroscience.

I was previously a research assistant at the Institute of Materials Research and Engineering and the Department of Chemistry at the National University of Singapore under the supervision of Provost's Chair Professor of Chemistry Xiaogang Liu. I was an Arnold and Mabel Beckman Fellow at the Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign under the supervison of Jay and Ann Schenck Professor of Chemistry Yi Lu on bio-inspired nanomaterials, metalloDNAzymes and sensors. Prior to this, in 2010, I joined the Institute of Bioengineering and Nanotechnology in the laboratories of Professor Ying Jackie Yi-Ru, Professor Zhiqiang Gao and Principal Research Scientist Yanbing Zu to work on ultrasensitive DNA nanoparticle based biosensors. Subsequently in 2014, I worked on upconversion nanomaterials for biological applications under the supervision of Professor Xiaogang Liu at the National University of Singapore and the Institute of Materials Research and Engineering. In Summer 2015, Kang Yong returned to the National University of Singapore, the Institute of Materials Research and Engineering and the Institute of Molecular and Cell Biology under the supervision of Professor Yin Thai Chan to work on semiconductor quantum dots and microfluidics applications.

I obtained my B.S. degree in Chemistry (Highest Distinction and Edmund J. James Scholar Honors) from the University of Illinois at Urbana-Champaign in 2017.

Education & Certifications

  • B.S. in Chemistry, University of Illinois at Urbana-Champaign, Chemistry (2017)

Contact

  • Academic
    lohky@stanford.edu
    University - Student Department: Chemistry Position: Graduate

Additional Info

  • Mail Code: 5080

Links

All Publications

  • Sharp-peaked lanthanide nanocrystals for near-infrared photoacoustic multiplexed differential imaging COMMUNICATIONS MATERIALS Loh, K., Li, L. S., Fan, J., Goh, Y., Liew, W., Davis, S., Zhang, Y., Li, K., Liu, J., Liang, L., Feng, M., Yang, M., Zhang, H., Ma, P., Feng, G., Mu, Z., Gao, W., Sum, T., Liu, B., Lin, J., Yao, K., Wang, L. V., Liu, X. 2024; 5 (1)

    View details for DOI 10.1038/s43246-024-00605-1

    View details for Web of Science ID 001296581200003

  • Genetically targeted chemical assembly of polymers specifically localized extracellularly to surface membranes of living neurons. Science advances Zhang, A., Loh, K. Y., Kadur, C. S., Michalek, L., Dou, J., Ramakrishnan, C., Bao, Z., Deisseroth, K. 2023; 9 (32): eadi1870

    Abstract

    Multicellular biological systems, particularly living neural networks, exhibit highly complex organization properties that pose difficulties for building cell-specific biocompatible interfaces. We previously developed an approach to genetically program cells to assemble structures that modify electrical properties of neurons in situ, opening up the possibility of building minimally invasive cell-specific structures and interfaces. However, the efficiency and biocompatibility of this approach were challenged by limited membrane targeting of the constructed materials. Here, we design a method for highly localized expression of enzymes targeted to the plasma membrane of primary neurons, with minimal intracellular retention. Next, we show that polymers synthesized in situ by this approach form dense extracellular clusters selectively on the targeted cell membrane and that neurons remain viable after polymerization. Last, we show generalizability of this method across a range of design strategies. This platform can be readily extended to incorporate a broad diversity of materials onto specific cell membranes within tissues and may further enable next-generation biological interfaces.

    View details for DOI 10.1126/sciadv.adi1870

    View details for PubMedID 37556541

  • An exercise-inducible metabolite that suppresses feeding and obesity. Nature Li, V. L., He, Y., Contrepois, K., Liu, H., Kim, J. T., Wiggenhorn, A. L., Tanzo, J. T., Tung, A. S., Lyu, X., Zushin, P. H., Jansen, R. S., Michael, B., Loh, K. Y., Yang, A. C., Carl, C. S., Voldstedlund, C. T., Wei, W., Terrell, S. M., Moeller, B. C., Arthur, R. M., Wallis, G. A., van de Wetering, K., Stahl, A., Kiens, B., Richter, E. A., Banik, S. M., Snyder, M. P., Xu, Y., Long, J. Z. 2022

    Abstract

    Exercise confers protection against obesity, type 2 diabetes and other cardiometabolic diseases1-5. However, the molecular and cellular mechanisms that mediate the metabolic benefits of physical activity remain unclear6. Here we show that exercise stimulates the production of N-lactoyl-phenylalanine (Lac-Phe), a blood-borne signalling metabolite that suppresses feeding and obesity. The biosynthesis of Lac-Phe from lactate and phenylalanine occurs in CNDP2+ cells, including macrophages, monocytes and other immune and epithelial cells localized to diverse organs. In diet-induced obese mice, pharmacological-mediated increases in Lac-Phe reduces food intake without affecting movement or energy expenditure. Chronic administration of Lac-Phe decreases adiposity and body weight and improves glucose homeostasis. Conversely, genetic ablation of Lac-Phe biosynthesis in mice increases food intake and obesity following exercise training. Last, large activity-inducible increases in circulating Lac-Phe are also observed in humans and racehorses, establishing this metabolite as a molecular effector associated with physical activity across multiple activity modalities and mammalian species. These data define a conserved exercise-inducible metabolite that controls food intake and influences systemic energy balance.

    View details for DOI 10.1038/s41586-022-04828-5

    View details for PubMedID 35705806

  • Topological supramolecular network enabled high-conductivity, stretchable organic bioelectronics. Science (New York, N.Y.) Jiang, Y., Zhang, Z., Wang, Y. X., Li, D., Coen, C. T., Hwaun, E., Chen, G., Wu, H. C., Zhong, D., Niu, S., Wang, W., Saberi, A., Lai, J. C., Wu, Y., Wang, Y., Trotsyuk, A. A., Loh, K. Y., Shih, C. C., Xu, W., Liang, K., Zhang, K., Bai, Y., Gurusankar, G., Hu, W., Jia, W., Cheng, Z., Dauskardt, R. H., Gurtner, G. C., Tok, J. B., Deisseroth, K., Soltesz, I., Bao, Z. 2022; 375 (6587): 1411-1417

    Abstract

    Intrinsically stretchable bioelectronic devices based on soft and conducting organic materials have been regarded as the ideal interface for seamless and biocompatible integration with the human body. A remaining challenge is to combine high mechanical robustness with good electrical conduction, especially when patterned at small feature sizes. We develop a molecular engineering strategy based on a topological supramolecular network, which allows for the decoupling of competing effects from multiple molecular building blocks to meet complex requirements. We obtained simultaneously high conductivity and crack-onset strain in a physiological environment, with direct photopatternability down to the cellular scale. We further collected stable electromyography signals on soft and malleable octopus and performed localized neuromodulation down to single-nucleus precision for controlling organ-specific activities through the delicate brainstem.

    View details for DOI 10.1126/science.abj7564

    View details for PubMedID 35324282

  • Recent advances in upconversion nanocrystals: Expanding the kaleidoscopic toolbox for emerging applications NANO TODAY Zheng, K., Loh, K., Wang, Y., Chen, Q., Fan, J., Jung, T., Nam, S., Suh, Y., Liu, X. 2019; 29

    View details for DOI 10.1016/j.nantod.2019.100797

    View details for Web of Science ID 000504503800010

  • Discovery of and Insights into DNA "Codes" for Tunable Morphologies of Metal Nanoparticles SMALL Satyavolu, N., Loh, K., Tan, L., Lu, Y. 2019; 15 (26): e1900975

    Abstract

    The discovery and elucidation of genetic codes has profoundly changed not only biology but also many fields of science and engineering. The fundamental building blocks of life comprises of four simple deoxyribonucleotides and yet their combinations serve as the carrier of genetic information that encodes for proteins that can carry out many biological functions due to their unique functionalities. Inspired by nature, the functionalities of DNA molecules have been used as a capping ligand for controlling morphology of nanomaterials, and such a control is sequence dependent, which translates into distinct physical and chemical properties of resulting nanoparticles. Herein, an overview on the use of DNA as engineered codes for controlling the morphology of metal nanoparticles, such as gold, silver, and Pd-Au bimetallic nanoparticles is provided. Fundamental insights into rules governing DNA controlled growth mechanisms are also summarized, based on understanding of the affinity of the DNA nucleobases to various metals, the effect of combination of nucleobases, functional modification of DNA, the secondary structures of DNA, and the properties of the seed employed. The resulting physical and chemical properties of these DNA encoded nanomaterials are also reviewed, while perspectives into the future directions of DNA-mediated nanoparticle synthesis are provided.

    View details for DOI 10.1002/smll.201900975

    View details for Web of Science ID 000478599600003

    View details for PubMedID 31074939

    View details for PubMedCentralID PMC6663601

  • Recent Advances in the Catalytic Synthesis of 4-Quinolones CHEM Shen, C., Wang, A., Xu, J., An, Z., Loh, K., Zhang, P., Liu, X. 2019; 5 (5): 1059–1107

    View details for DOI 10.1016/j.chempr.2019.01.006

    View details for Web of Science ID 000467750100010

  • Optical Control of Metal Ion Probes in Cells and Zebrafish Using Highly Selective DNAzymes Conjugated to Upconversion Nanoparticles JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Yang, Z., Loh, K., Chu, Y., Feng, R., Satyavolu, N., Xiong, M., Huynh, S., Hwang, K., Li, L., Xing, H., Zhang, X., Chelma, Y. R., Gruebele, M., Lu, Y. 2018; 140 (50): 17656–65

    Abstract

    Spatial and temporal distributions of metal ions in vitro and in vivo are crucial in our understanding of the roles of metal ions in biological systems, and yet there is a very limited number of methods to probe metal ions with high space and time resolution, especially in vivo. To overcome this limitation, we report a Zn2+-specific near-infrared (NIR) DNAzyme nanoprobe for real-time metal ion tracking with spatiotemporal control in early embryos and larvae of zebrafish. By conjugating photocaged DNAzymes onto lanthanide-doped upconversion nanoparticles (UCNPs), we have achieved upconversion of a deep tissue penetrating NIR 980 nm light into 365 nm emission. The UV photon then efficiently photodecages a substrate strand containing a nitrobenzyl group at the 2'-OH of adenosine ribonucleotide, allowing enzymatic cleavage by a complementary DNA strand containing a Zn2+-selective DNAzyme. The product containing a visible FAM fluorophore that is initially quenched by BHQ1 and Dabcyl quenchers is released after cleavage, resulting in higher fluorescent signals. The DNAzyme-UCNP probe enables Zn2+ sensing by exciting in the NIR biological imaging window in both living cells and zebrafish embryos and detecting in the visible region. In this study, we introduce a platform that can be used to understand the Zn2+ distribution with spatiotemporal control, thereby giving insights into the dynamical Zn2+ ion distribution in intracellular and in vivo models.

    View details for DOI 10.1021/jacs.8b09867

    View details for Web of Science ID 000454383400047

    View details for PubMedID 30427666

    View details for PubMedCentralID PMC6473182

  • Gapping into Ultrahigh Surface-Enhanced Raman Scattering Amplification ACS CENTRAL SCIENCE Loh, K., Liu, X. 2018; 4 (2): 137–39

    View details for DOI 10.1021/acscentsci.8b00045

    View details for Web of Science ID 000426613700003

    View details for PubMedID 29532011

    View details for PubMedCentralID PMC5833008

  • The improved sensitive detection of C-reactive protein based on the chemiluminescence immunoassay by employing monodispersed PAA-Au/Fe3O4 nanoparticles and zwitterionic glycerophosphoryl choline JOURNAL OF MATERIALS CHEMISTRY B Xing, Y., Gao, Q., Zhang, Y., Ma, L., Loh, K., Peng, M., Chen, C., Cui, Y. 2017; 5 (21): 3919–26

    View details for DOI 10.1039/c7tb00637c

    View details for Web of Science ID 000402741900014

  • DNAzyme sensors for detection of metal ions in the environment and imaging them in living cells CURRENT OPINION IN BIOTECHNOLOGY McGhee, C. E., Loh, K., Lu, Y. 2017; 45: 191–201

    Abstract

    The on-site and real-time detection of metal ions is important for environmental monitoring and for understanding the impact of metal ions on human health. However, developing sensors selective for a wide range of metal ions that can work in the complex matrices of untreated samples and cells presents significant challenges. To meet these challenges, DNAzymes, an emerging class of metal ion-dependent enzymes selective for almost any metal ion, have been functionalized with fluorophores, nanoparticles and other imaging agents and incorporated into sensors for the detection of metal ions in environmental samples and for imaging metal ions in living cells. Herein, we highlight the recent developments of DNAzyme-based fluorescent, colorimetric, SERS, electrochemical and electrochemiluminscent sensors for metal ions for these applications.

    View details for DOI 10.1016/j.copbio.2017.03.002

    View details for Web of Science ID 000403138500026

    View details for PubMedID 28458112

    View details for PubMedCentralID PMC5503749

  • A Broadly Applicable Assay for Rapidly and Accurately Quantifying DNA Surface Coverage on Diverse Particles BIOCONJUGATE CHEMISTRY Yu, H., Xu, X., Liang, P., Loh, K., Guntupalli, B., Roncancio, D., Xiao, Y. 2017; 28 (4): 933–43

    Abstract

    DNA-modified particles are used extensively for applications in sensing, material science, and molecular biology. The performance of such DNA-modified particles is greatly dependent on the degree of surface coverage, but existing methods for quantitation can only be employed for certain particle compositions and/or conjugation chemistries. We have developed a simple and broadly applicable exonuclease III (Exo III) digestion assay based on the cleavage of phosphodiester bonds-a universal feature of DNA-modified particles-to accurately quantify DNA probe surface coverage on diverse, commonly used particles of different compositions, conjugation chemistries, and sizes. Our assay utilizes particle-conjugated, fluorophore-labeled probes that incorporate two abasic sites; these probes are hybridized to a complementary DNA (cDNA) strand, and quantitation is achieved via cleavage and digestion of surface-bound probe DNA via Exo III's apurinic endonucleolytic and exonucleolytic activities. The presence of the two abasic sites in the probe greatly speeds up the enzymatic reaction without altering the packing density of the probes on the particles. Probe digestion releases a signal-generating fluorophore and liberates the intact cDNA strand to start a new cycle of hybridization and digestion, until all fluorophore tags have been released. Since the molar ratio of fluorophore to immobilized DNA is 1:1, DNA surface coverage can be determined accurately based on the complete release of fluorophores. Our method delivers accurate, rapid, and reproducible quantitation of thiolated DNA on the surface of gold nanoparticles, and also performs equally well with other conjugation chemistries, substrates, and particle sizes, and thus offers a broadly useful assay for quantitation of DNA surface coverage.

    View details for DOI 10.1021/acs.bioconjchem.6b00660

    View details for Web of Science ID 000399965800012

    View details for PubMedID 28156100

    View details for PubMedCentralID PMC5648061