@article{neupane_chase_zhao_wang_he_2021, title={Optical properties of segmented Ag-Au wire at single particle level studied with a home-built micro-spectrometer}, ISSN={["2577-8196"]}, DOI={10.1002/eng2.12439}, abstractNote={Abstract}, journal={ENGINEERING REPORTS}, author={Neupane, Bhanu B. and Chase, Thomas E. and Zhao, Luyang and Wang, Gufeng and He, Lin}, year={2021}, month={Jul} }
 @misc{giri_pandey_shrestha_pokharel_ligler_neupane_2021, title={Review of analytical performance of COVID-19 detection methods}, volume={413}, ISSN={["1618-2650"]}, DOI={10.1007/s00216-020-02889-x}, abstractNote={Abstract}, number={1}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Giri, Basant and Pandey, Shishir and Shrestha, Retina and Pokharel, Krisha and Ligler, Frances S. and Neupane, Bhanu B.}, year={2021}, month={Jan}, pages={35–48} }
 @article{neupane_zhong_wang_2020, title={Study on self-assembly of colloidal particles at high ionic strength with stimulated emission depletion microscopy}, volume={2}, ISSN={["2577-8196"]}, DOI={10.1002/eng2.12233}, abstractNote={Abstract}, number={9}, journal={ENGINEERING REPORTS}, author={Neupane, Bhanu B. and Zhong, Yaning and Wang, Gufeng}, year={2020}, month={Sep} }
 @article{chen_neupane_li_su_wang_2016, title={Investigating axial diffusion in cylindrical pores using confocal single-particle fluorescence correlation spectroscopy}, volume={37}, ISSN={["1522-2683"]}, DOI={10.1002/elps.201600158}, abstractNote={We explored the feasibility of using confocal fluorescence correlation spectroscopy to study small nanoparticle diffusion in hundred‐nanometer‐sized cylindrical pores. By modeling single particle diffusion in tube‐like confined three‐dimensional space aligned parallel to the confocal optical axis, we showed that two diffusion dynamics can be observed in both original intensity traces and the autocorrelation functions (ACFs): the confined two‐dimensional lateral diffusion and the unconfined one‐dimensional (1D) axial diffusion. The separation of the axial and confined lateral diffusion dynamics provides an opportunity to study diffusions in different dimensions separately. We further experimentally studied 45 nm carboxylated polystyrene particles diffusing in 300 nm alumina pores. The experimental data showed consistency with the simulation. To extract the accurate axial diffusion coefficient, we found that a 1D diffusion model with a Lorentzian axial collection profile needs to be used to analyze the experimental ACFs. The diffusion of the 45 nm nanoparticles in polyethyleneglycol‐passivated 300 nm pores slowed down by a factor of ∼2, which can be satisfactorily explained by hydrodynamic frictions.}, number={15-16}, journal={ELECTROPHORESIS}, author={Chen, Fang and Neupane, Bhanu and Li, Peiyuan and Su, Wei and Wang, Gufeng}, year={2016}, month={Aug}, pages={2129–2138} }
 @article{chen_garcia-lopez_jin_neupane_chu_tour_wang_2016, title={Moving Kinetics of Nanocars with Hydrophobic Wheels on Solid Surfaces at Ambient Conditions}, volume={120}, ISSN={["1932-7447"]}, DOI={10.1021/acs.jpcc.6b01249}, abstractNote={Motivated by “driving” nanoscopic nanocars on solid substrate surfaces at ambient conditions, we studied the moving kinetics of nanocars on differently modified surfaces. Single molecule fluorescence imaging was used to track the nanocar movement so that the molecules were minimally perturbed. On freshly cleaned, hydroxylated glass surfaces, nanocars with hydrophobic adamantane wheels can diffuse with a relatively large diffusion coefficient of 7.6 × 10–16 m2/s. Both the number of moving molecules and the mobility of the moving molecules decreased over time when the sample was exposed in the air. Similar declinations in movement were observed on a poly(ethylene glycol) (PEG)-modified glass surface, but the declination rate was lowered. The slowing of molecular surface diffusion is correlated to the hydrophobicity of the surface and is likely caused by the adsorption of hydrophobic molecules from the air. A proposed sticky-spots model explains the decreasing apparent diffusion coefficient of the hydrophobi...}, number={20}, journal={JOURNAL OF PHYSICAL CHEMISTRY C}, author={Chen, Fang and Garcia-Lopez, Victor and Jin, Tao and Neupane, Bhanu and Chu, Pin-Lei E. and Tour, James and Wang, Gufeng}, year={2016}, month={May}, pages={10887–10894} }
 @article{neupane_chen_wei_fang_ligler_wang_2016, title={Nanosecond Time-Resolution Study of Gold Nanorod Rotation at the Liquid-Solid Interface}, volume={17}, ISSN={["1439-7641"]}, DOI={10.1002/cphc.201600174}, abstractNote={Abstract}, number={14}, journal={CHEMPHYSCHEM}, author={Neupane, Bhanu and Chen, Fang and Wei, Yanli and Fang, Ning and Ligler, Frances S. and Wang, Gufeng}, year={2016}, month={Jul}, pages={2218–2224} }
 @article{pacardo_neupane_rikard_lu_mo_mishra_tracy_wang_ligler_gu_2015, title={A dual wavelength-activatable gold nanorod complex for synergistic cancer treatment}, volume={7}, ISSN={["2040-3372"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000357805700034&KeyUID=WOS:000357805700034}, DOI={10.1039/c5nr01568e}, abstractNote={A multifunctional gold nanorod complex was formulated for synergistic anticancer treatment upon ultraviolet (UV) and infrared (IR) light dual irradiations.}, number={28}, journal={NANOSCALE}, author={Pacardo, Dennis B. and Neupane, Bhanu and Rikard, S. Michaela and Lu, Yue and Mo, Ran and Mishra, Sumeet R. and Tracy, Joseph B. and Wang, Gufeng and Ligler, Frances S. and Gu, Zhen}, year={2015}, pages={12096–12103} }
 @article{pacardo_neupane_wang_gu_walker_ligler_2015, title={A temperature microsensor for measuring laser-induced heating in gold nanorods}, volume={407}, ISSN={["1618-2650"]}, DOI={10.1007/s00216-014-8222-9}, abstractNote={Measuring temperature is an extensively explored field of analysis, but measuring a temperature change in a nanoparticle is a new challenge. Here, a microsensor is configured to measure temperature changes in gold nanorods in solution upon laser irradiation. The device consists of a silicon wafer coated with silicon nitride in which a microfabricated resistance temperature detector was embedded and attached to a digital multimeter. A polydimethylsiloxane mold served as a microcontainer for the sample attached on top of the silicon membrane. This enables laser irradiation of the gold nanorods and subsequent measurement of temperature changes. The results showed a temperature increase of 8 to 10 °C and good correlation with theoretical calculations and bulk sample direct temperature measurements. These results demonstrate the suitability of this simple temperature microsensor for determining laser-induced heating profiles of metallic nanomaterials; such measurements will be essential for optimizing therapeutic and catalytic applications.}, number={3}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Pacardo, Dennis B. and Neupane, Bhanu and Wang, Gufeng and Gu, Zhen and Walker, Glenn M. and Ligler, Frances S.}, year={2015}, month={Jan}, pages={719–725} }
 @article{neupane_jin_mellor_loboa_ligler_wang_2015, title={Continuous-wave stimulated emission depletion microscope for imaging actin cytoskeleton in fixed and live cells}, volume={15}, number={9}, journal={Sensors (Basel, Switzerland)}, author={Neupane, B. and Jin, T. and Mellor, L. F. and Loboa, E. G. and Ligler, F. S. and Wang, G. F.}, year={2015}, pages={24178–24190} }
 @misc{neupane_ligler_wang_2014, title={Review of recent developments in stimulated emission depletion microscopy: Applications on cell imaging}, volume={19}, number={8}, journal={Journal of Biomedical Optics}, author={Neupane, B. and Ligler, F. S. and Wang, G. F.}, year={2014} }
 @misc{stender_marchuk_liu_sander_meyer_smith_neupane_wang_li_cheng_et al._2013, title={Single Cell Optical Imaging and Spectroscopy}, volume={113}, ISSN={["1520-6890"]}, DOI={10.1021/cr300336e}, abstractNote={In his 1665 treatise, Micrographia, Robert Hooke described the many observations he had made using a microscope, including compartment-like structures in cork samples that he termed ‘cells’.1 In the three and a half centuries since Hooke’s day, both the microscope and our understanding of the cell have been vastly improved upon, and the current outlook suggests that the symbiotic relationship between the microscope and the cell will continue to flourish into the foreseeable future. The cell is a basic yet complicated ‘unit’ of interest to biology, just as the atom is to chemists. Ultimately, scientists want to ‘see to believe’ when it comes to an explanation of the complex inner workings of cells, but therein lies a complication. Seeing is not always a possibility in biological systems. Size, speed, sensitivity, and additional concerns plague the microscopist who wants to peek inside of a cell. Enter a variety of molecular and nanoparticle probes that are capable of tagging and pinpointing the location of biological components that would otherwise be invisible under the microscope. Advances in laser, camera, and imaging processing technologies have also played a crucial role in the burgeoning field of single cell imaging, because they have brought into view the fast processes that would normally escape the human eye. 
 
The purpose of this review is to highlight the key advances that have occurred in the past several years in the field of single cell optical imaging. It is not our intent to provide a comprehensive review of the types of experiments or the areas of cell research that are ongoing. Reviews with a distinctly biological flavor have been published recently, and these alternative reviews focus on specific details of the cell and the processes that occur within.2-7 Likewise, exceptional review papers that have discussed the full spectrum of nanoparticle probes and their properties have appeared recently.6-12 This review is designed to give an overview of the tools that are being specifically used to accomplish single cell imaging. As such, much of our emphasis in the first several sections of this paper is on imaging platforms, with a focus on design details that are important to single cell imaging experiments. Next we emphasize specific imaging experiments that highlight the types of findings that are possible at the nexus of microscopy, nanoprobes, and live cells. Particular attention is paid to the emerging orientation and rotational tracking of single probes linked to mechanistic functions and differentiated structures of biological interest. Finally, we provide a brief, yet rather complete, summary of single cell manipulation techniques.}, number={4}, journal={CHEMICAL REVIEWS}, author={Stender, Anthony S. and Marchuk, Kyle and Liu, Chang and Sander, Suzanne and Meyer, Matthew W. and Smith, Emily A. and Neupane, Bhanu and Wang, Gufeng and Li, Junjie and Cheng, Ji-Xin and et al.}, year={2013}, month={Apr}, pages={2469–2527} }
 @article{neupane_chen_sun_chiu_wang_2013, title={Tuning donut profile for spatial resolution in stimulated emission depletion microscopy}, volume={84}, number={4}, journal={Review of Scientific Instruments}, author={Neupane, B. and Chen, F. and Sun, W. and Chiu, D. T. and Wang, G. F.}, year={2013} }
 @article{neupane_zhao_wang_2013, title={Up-Conversion Luminescence of Gold Nanospheres When Excited at Nonsurface Plasmon Resonance Wavelength by a Continuous Wave Laser}, volume={13}, ISSN={["1530-6992"]}, DOI={10.1021/nl401505p}, abstractNote={We show that, when gold nanospheres are excited at the red side of the surface plasmon resonance (SPR) wavelength at 592 nm by a continuous wave (CW) laser, they give substantial up-converted luminescence in the SPR wavelength range. The luminescence intensity scales as a second-order function of the excitation power, with a quantum yield ~1/50 of down-conversion luminescence when illuminated at a power of 30 MW/cm(2). The luminescence spectrum is completely different than the SPR profile, indicating a new emission mechanism possibly involving interband transitions coupled with phonons or localized vibration of neighboring gold atoms. Such luminescence is also observed to be substantial for short gold nanorods with an aspect ratio of ~2 but weak for bulk gold. This study provides new insight to the understanding of gold nanoparticle luminescence and opens a new detection scheme for gold nanoparticle-based biological imaging.}, number={9}, journal={NANO LETTERS}, author={Neupane, Bhanu and Zhao, Luyang and Wang, Gufeng}, year={2013}, month={Sep}, pages={4087–4092} }