नमस्कार | שלום | Hallo | Bonjour | Mabuhay | 你好
नमस्कार | שלום | Hallo | Bonjour | Mabuhay | 你好
Present Affiliation:
Postdoctoral fellow at the Laboratory of Physical Epigenetics (Prof. Yuval Ebenstein), School of Chemistry, Faculty of Exact Sciences, Tel Aviv University, Israel
Educational Qualifications
Ph.D. Chemistry: School of Chemical Sciences, Indian Institute of Technology (IIT) Mandi, Kamand, Mandi, Himachal Pradesh - 175005, India
(Ph.D. Thesis [Outstanding]: Tuning Fluorescence Blinking in Quantum Dots for Room Temperature Single Photon Emission and Super Resolution Microscopy, from the lab of Prof. Chayan Kanti Nandi: Website)
M.Sc. Chemistry: School of Basic Sciences, Indian Institute of Technology (IIT) Mandi, Kamand, Mandi, Himachal Pradesh - 175005, India
(M.Sc. Thesis: Fluorescence Correlation Spectroscopy on Carbon Dots Systems)
B.Sc. (H) Chemistry: Department of Chemistry, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi - 110025, India
XII: Kendriya Vidyalaya Keshav Puram, Lawrence Road, New Delhi - 110035, India [CBSE]
X: Kendriya Vidyalaya Keshav Puram, Lawrence Road, New Delhi - 110035, India [CBSE]
Broad Research Areas
Single-Molecule Optical Genome Mapping | Epigenetics | Nanofluidics | Single-Molecule Spectroscopy | Super-Resolution Microscopy | Quantum Dot Photophysics
Short Professional Bio
I am a postdoctoral fellow in the Laboratory of Physical Epigenetics of Prof. Yuval Ebenstein at Tel Aviv University, where I work on single-molecule optical genome mapping and epigenetic profiling. My current work spans the full experimental chain, from the design and fabrication of nanoslit devices that stretch individual DNA molecules to the imaging and analysis pipeline that converts these images into genomic and epigenetic read-outs. I recently presented this work, “Investigation of Single-Molecule Short DNA-RNA Polymers in Nanochannels”, as an oral presentation at the LMI Annual Retreat (Ein Gedi, September 2026).
I completed my Ph.D. in Chemistry at IIT Mandi in July 2025 under Prof. Chayan Kanti Nandi, with a thesis rated Outstanding: “Tuning Fluorescence Blinking in Quantum Dots for Room Temperature Single Photon Emission and Super Resolution Microscopy”. Using ensemble and single-particle spectroscopy together, I identified an excitation-wavelength-dependent dark fraction that lowers the quantum yield of CdTe quantum dots (QDs). I also elucidated the mechanism of room-temperature single-photon emission in CdTeSe QDs, and I tuned QD blinking through protein conjugation to make the dots suitable for localisation-based super-resolution imaging of lysosomes.
My expertise lies in building optical setups for single-molecule spectroscopy and super-resolution microscopy (STORM and SRRF), photon-counting measurements (TCSPC, FLIM, FCS and Hanbury Brown–Twiss antibunching), and writing batch-analysis tools in ImageJ macro, MATLAB and Python. My work has resulted in 25 peer-reviewed articles and one granted patent.
Research Areas
Optical Genome Mapping
Nanoslit device: DNA enters the microchannel as random coils and is linearised under nanoconfinement, so labels along each molecule can be resolved.
From single molecules to read-out: labelling, stretching and imaging, U-Net reconstruction, barcode extraction and alignment to the reference genome.
In the Ebenstein lab, I work on single-molecule optical genome mapping, in which individual DNA molecules are fluorescently labelled, linearised in nanoconfined channels, and imaged to read out genomic and epigenetic information directly from single molecules. Confinement in nanoslits stretches DNA well beyond its coiled conformation in solution, so that the spatial pattern of labels along each molecule, its optical barcode, can be resolved and aligned to a reference genome.
My work spans this full chain. I design and fabricate nanoslit devices by photolithography, reactive-ion etching (RIE), multilayer alignment and glass bonding, and I work with the downstream imaging and analysis pipeline, from deep-learning (U-Net) reconstruction of raw fields of view to barcode read-out. I recently presented part of this work, “Investigation of Single-Molecule Short DNA-RNA Polymers in Nanochannels”, as an oral presentation at the LMI Annual Retreat (Ein Gedi, September 2026).
Single Molecule/Particle Spectroscopy
Single particles or molecules often exhibit inconsistent fluorescence emission as a function of time, a phenomenon known as blinking or intermittency
Single-particle/molecule spectroscopy is a technique that focuses on studying individual particle or molecule rather than examining a large ensemble of many particles. This approach eliminates the averaging effects found in ensemble measurements, leading to a clearer understanding of the sample. By using single molecule/particle technique, we understand the deeper insights onto the photophysical properties and their spectral heterogeneity in the sample. In our lab, we have developed a custom-built single molecule/particle spectroscopy setup to study the photophysics of quantum and nanomaterials at the single-particle level. We also utilize fluorescence correlation spectroscopy (FCS), a unique diffusion-based technique to further understand the fluorescence properties of the materials.
The fluorescence spectroscopic analysis of single particles revealed some exciting phenomena that were previously unknown at the bulk level. The single molecule/particle technique also help in understanding the fluorescence blinking or intermittency, which plays an important role in deciding the fate of the fluorescent material for their optoelectronic applications (also shown in above figure).
Using the combination of ensemble and single particle fluorescence spectroscopy, I was able to unveil the existence of excitation wavelength dependent dark fractions in water dispersible CdTe quantum dots. In another work, i tuned the single quantum dot's fluorescence blinking to utilise them in super resolution micrsocopy (localisation based).
Notable publications
Nanoscale, 2025, 17, 7, 3919-3929. https://doi.org/10.1039/D4NR04344H
ChemNanoMat. 2022, 8, 10, e202200235. https://doi.org/10.1002/cnma.202200235
Super Resolution Microscopy
Improvement in the lysosomal spatial resolution using the Super Resolution Imaging using STORM and SRRF
Light microscopy encounters limitations due to Abbe's diffraction limit, which arises from the wave nature of light. This limit restricts the resolution of structures smaller than 300 nm, posing significant challenges in studying sub-cellular organelles in detail. To explore these smaller structures, researchers often turn to techniques such as near-field microscopy and TEM. However, these methods have their own drawbacks, particularly in the context of live-cell microscopy and the study of subcellular dynamics.
Super-resolution microscopy techniques have been developed to achieve resolution beyond the diffraction limit using light microscopy. We have developed a home-built setup which is both utilised for single molecule/particle spectroscopy as well as the super resolution microscopy. However for utilising the localisation based super resolution microscopy (SMLM or STORM), the fluorescence marker needs to follow few set of rules
This setup contains 4 lasers (405, 488, 532, 639 nm) directed to a 2 mirror setup for easy alignemet. all lasers are combined using high pass dichroic filters. then the beam profile is tuned by focusing the combined beam to a 50 um pinhole. the diffracted pattern obtained via pinhole is then expanded using 2 x 4x beam expanders. the beam is then focused to the back focal plane of the Nikon Ti eclipse inverted microscope's 100x oil immersion objective.
Notable publication
ChemNanoMat. 2022, 8, 10, e202200235. https://doi.org/10.1002/cnma.202200235
The Journal of Physical Chemistry Letters, 2025, 16, 23, 5868-5877. https://doi.org/10.1021/acs.jpclett.5c00884
Optical setups in the lab of Prof. Nandi
Room-Temperature Single Photon Emission
Hanbury-Brown and Twiss (HBT) Setup: Experimental setup to determine the purity of single photon emission
Quantum technologies have the potential to revolutionize various fields, including computing, information processing, sensing, metrology, imaging, cryptography, and communication. These technologies rely on quantum bits, or qubits, which are the quantum analogues of classical bits. Qubits can be implemented using different two-level physical systems, such as superconducting qubits, trapped ion qubits, and photonic qubits. Superconducting qubits use superconducting circuits, trapped ion qubits use atoms or ions, and photonic qubits utilize photons with different colors, phases, or polarizations of photons for qubit generation. Photonic qubits offer several advantages over other types. They can be easily transmitted through optical fibers, are less susceptible to decoherence due to minimal contact with environmental factors, and are a promising candidate for operation at non-zero temperature. In the context of photonic qubits, photons serve as qubits, and single photons are necessary for implementing quantum logic gates and communication protocols.
To realize a photonic qubit, a single photon source is required. A single photon source must generate highly pure single photons on demand with deterministic emission. In our lab, we have utilised colloidal quantum dots to generate single photons with ultra-high purity at room temperature. I was also curious to understand the mechanism of Single Photon Emission from the colloidal quantum dots by utilising various spectroscopic tools at ensemble and single particle level. This detailed understanding can help design and engineer the single photon sources at room temperature.
Notable publication
The Journal of Physical Chemistry Letters, 2025, 16, 23, 5868-5877. https://doi.org/10.1021/acs.jpclett.5c00884