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Helmholtz Munich | IBMI

Nanomedicine & Biomarkers

Gujrati Lab

Our research is focused on advancing contrast enhancement, drug-delivery strategies and biomarker studies to deliver preclinical information using optical and optoacoustic imaging techniques.

Gujrati Lab

Our research is focused on advancing contrast enhancement, drug-delivery strategies and biomarker studies to deliver preclinical information using optical and optoacoustic imaging techniques.

About our Research

The Nanomedicine & Biomarkers team conducts interdisciplinary research at the biology, chemistry, and engineering interface. Within this collaborative environment, researchers are developing multifunctional nanotechnology tools using bio-inspired and synthetic materials that have the potential to map biomarkers and facilitate early and precise targeting of diseased cells for imaging and therapy. We are using nanotechnology and advanced imaging tools to investigate the molecular differences between metabolic disorders, cancer, and the microenvironment of healthy tissues. These studies offer insights into innovative approaches for disease diagnosis and treatment. Our research focuses on Optical and Optoacoustic Imaging, Bioengineering, Contrast Agents, Drug Delivery, and Pre-clinical application areas such as Cancer Imaging, Metabolic Imaging, Regenerative Therapy and Photo Therapy.

  • Contrast Enhancement and Drug Delivery: We are interested in the rational design and synthesis of bioengineered and synthetic nano-agents suitable for optoacoustic imaging,  near-infrared fluorescence imaging and drug delivery. Our ongoing research aims to develop multifunctional, activatable agents for contrast enhancement, disease monitoring and therapeutic response. For example, we are developing nano-agents from bio-engineered cells and synthetic (organic and inorganic) materials, studying their interactions with cells and tissues, and developing safe and effective nano-medicines by testing them in preclinical disease models. 
  • Metabolic and Vascular Imaging: We study preclinical disease models using state-of-the-art label-free Multi-spectral optoacoustic tomography (MSOT) imaging. MSOT allows us to visualise physiological parameters associated with metabolic processes and hemodynamics. In particular, changes in tissue oxygenation, gradients in oxygenated and deoxygenated hemoglobin, as well as imaging of blood vessels and tissue perfusion. MSOT-based molecular or biomarker imaging is particularly useful for predicting the disease state and therapy efficacy.
  • Phototherapy treatment monitoring:  Our developed nano-agents help in achieving efficient light-to-heat conversion or generation of oxygen radicals and precise disease targeting. When exposed to near-infrared (NIR) light in the region of interest, nano-agents cause local heating (Hyperthermia) or generate reactive oxygen species (Photodynamic therapy) due to enhanced optical absorption to trigger reactions in the tissue microenvironment and lead to targeted cell death. Our focus is on designing light-activatable nanoagents for targeted cell killing and understanding the biological mechanisms triggered by heat or reactive oxygen species through optoacoustic imaging technology- MSOT.

Our Focus

Smart Nanomedicines

In this project, our focus is on cell engineering and development of bio-inspired nanocarriers for theranostic applications.


Over the past decade, research on extracellular vesicles (EVs) has increased dramatically in various fields. Their importance stems from their presence in biological fluids, their natural packaging and the delivery of biomolecules such as lipids, proteins, and RNA. EVs are now emerging as biomarkers for diseases like cancer, neurological disorders, etc. Their ability to encapsulate biomolecules and cross biological barriers, together with their potential for bioengineering, maks them ideal candidates for targeted drug delivery and disease diagnosis.

Research focus

  • Engineering EVs for optoacoustic imaging
  • Tumor-specific EVs for improved detection and drug delivery
  • EVs-augmented optoacoustics-guided hyperthermia and immunotherapy

Contrast Agents

Exogenous synthetic contrast agents are required for contrast-enhanced imaging and functional analysis. We are focusing on the development of contrast agents with absorption in the NIR-I and NIR-II windows.


FDA-approved fluorescent dyes have wide clinical applications in fluorescence imaging. However, these contrast agents are unsuitable for longitudinal imaging due to poor photostability, low photothermal conversion, and inefficient optoacoustic generation. There is an ongoing need for novel synthetic approaches to develop contrast agents with improved photothermal and optoacoustic generation properties.

Research focus

  • Design and synthesis of dyes for NIR-I and NIR-II optoacoustic imaging
  • Photo-transformable (photoactivation, photoswitching and photoconversion) dyes for in vivo biomolecule tracking
  • pH-sensitive optoacoustic dyes for sensitive visualisation of the tumor microenvironment
  • Multifunctional theranostics for imaging and phototherapy

Multi-Spectral Optoacoustic Tomography (MSOT):

MSOT captures images at different wavelengths and resolves spectral signatures, which helps to visualise and quantify optoacoustic signals from across the body due to different chromophores in tissue.


MSOT produces an anatomical and functional image at a specific wavelength using photo-absorbers such as oxy- and deoxyhemoglobin, melanin, fat, collagen, water, and various natural or introduced contrast agents. This provides translatable information and valuable insight into organ function in healthy and diseased states. Taking advantage of the real-time, high-resolution and sensitive imaging capability of MSOT, we are studying various diseases using preclinical cells and mouse models by visualising and quantifying optoacoustic signals from the organs at a depth of several centimetres.

Research focus

  • In vivo MSOT imaging of cancer, including Glioblastoma, Breast cancer, and Colon cancer
  • Gain new insights into diseases such as inflammation,  neurological disorders, ischaemia, fibrosis, etc.
  • Investigate the biodistribution of the optoacoustic agents in healthy and diseased mouse models
  • Investigate the biological barriers and implications for the delivery of nano-medicines
  • Monitor the drug delivery and therapeutic response by volumetric mapping of the tissues

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Brain Tomography



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Metabolic Imaging

Metabolic imaging provides valuable information about tissue function, disease state, and response to therapy by directly sensing metabolites or measuring metabolic processes in healthy and diseased states.


MSOT is used for non-invasive monitoring of metabolism and metabolic processes without the use of non-ionising radiations. MSOT enables the label-free measurement of oxygenated and deoxygenated hemoglobin and, thus, the tissue oxygenation state, or oxygen utilisation, which indicates the rate of metabolic processes.

Research focus

  • MSOT-based assessment of tissue oxygenated to deoxygenated hemoglobin gradients.
  • Monitoring metabolic changes in activated mouse adipose tissues.
  • Monitoring of metabolic changes in exercise and disease states, mitochondrial dysfunction, lipid metabolism, and cancer.


Hyperthermia and Photodynamic therapy: Optical materials can convert near-infrared (NIR) light into heat (hyperthermia or photothermal therapy), reactive oxygen species (photodynamic therapy), or UV/ visible photons (using upconversion nanomaterial) to produce cytotoxic effects or controlled drug release.


NIR light enables phototherapy with minimal toxic side effects and high penetration into the biological tissues. Importantly, the dose of NIR light can be regulated or improved for different aspects. In NIR-based phototherapy, the cytotoxic effects are mainly observed due to the direct cellular damage, increased vascular permeability or damage, immune response, and controlled drug delivery.

Research focus

  • Cancer treatment with hyperthermia
  • Photodynamic cancer therapy
  • Monitoring of photoimmunotherapy using MSOT
  • MSOT-based monitoring of phototherapy effects on the tissue microenvironment
  • Monitoring targeted drug delivery and therapeutic response using photoactivatable agents.

Our Researchers

Tianshou Cao

Ph.D student

Panhang Liu

Ph.D. Student
Ajay Kesharwani

Dr. Ajay Kesharwani

Porträt Divyesh Shelar

Dr. Divyesh Shelar


Our Topic

We develop nanoagents that are safe, non-toxic, have enhanced optical absorption, efficient optoacoustic generation, and effective light-to-heat conversion.  We use these smart nanoagents for precise disease targeting and controlled theranostic applications.

Our research interest:

  • Optoacoustic imaging
  • Contrast agents
  • Bioengineering and Biomaterials
  • Drug Delivery
  • Diagnosis and therapy monitoring
  • Cancer
  • Metabolic Diseases
  • Phototherapy (Hyperthermia and Photodynamic therapy)
  • Regenerative Therapy
  • Immunotherapy


2023 Cancer Nanotechnology

Liu N, Gujrati V*, Werner JPF, Mishra K, Anzenhofer P, Stiel AC, Mettenleiter G, Feuchtinger A, Walch A, Ntziachristos V*. Bacterial outer membrane vesicles as cationic dye carriers for optoacoustics-guided phototherapy of cancer.

2022 Nanophotonics

Liu N, O’Connor P, Gujrati V*, Anzenhofer P, Klemm U, Kleigrewe K, Sattler M, Plettenburg O, Ntziachristos V* Multifunctional croconaine nanoparticles for efficient optoacoustic imaging of deep tumors and photothermal therapy.

2022 Journal of Biomedical Optics

Madasamy A, Gujrati V, Ntziachristos V, Prakash J. Deep learning methods hold promise for light fluence compensation in three-dimensional optoacoustic imaging.

2021 Scientific Reports

Yun M, You SK, Nguyen VH, Prakash J, Glasl S, Gujrati V, Choy HE, Stiel AC, Min JJ, Ntziachristos V. Reporter gene-based optoacoustic imaging of E. coli targeted colon cancer in vivo.

2021 Photoacoustics

Liu N, Gujrati V, Najafabadi JM, Werner JPF, Klemm U, Tang L, Chen Z, Prakash J, Huang Y, Stiel A, Mettenleiter G, Aichler M, Blutke A, Walch A, Kleigrewe K, Razansky D, Sattler M, Ntziachristos V. Croconaine-based nanoparticles enable efficient optoacoustic imaging of murine brain tumors.

2021 Advanced Healthcare Materials

Liu, N., O'Connor, P., Gujrati, V*, Gorpas, D., Glasl, S., Blutke, A., Walch, A., Kleigrewe, K., Sattler, M., Plettenburg, O., Ntziachristos, V., Facile Synthesis of a Croconaine-Based Nanoformulation for Optoacoustic Imaging and Photothermal Therapy.

2021 Photons Plus Ultrasound: Imaging and Sensing

Prakash J, Seyedebrahimi MM, Ghazaryan A, Najafabadi JM, Gujrati V, Ntziachristos V. Cooled infrared optoacoustic spectroscopy (CIROAS) for accurate sensing based on water muting.

2021 Methods in Enzymology

Gujrati V, Ntziachristos V. Bioengineered bacterial vesicles for optoacoustics-guided phototherapy.

2020 Science Advances

Mishra K, Stankevych M, Werner JPF, Grassmann S, Gujrati V, Huang Y, Klemm U, Buchholz VR, Ntziachristos V, Stie ACl. Multiplexed whole-animal imaging with reversibly switchable optoacoustic proteins.

2020 Light: Science & Applications

Li J, Chekkoury A, Prakash J, Glasl S, Vetschera P, Koberstein-Schwarz B, Olefir I, Gujrati V, Omar M, Ntziachristos V. Spatial heterogeneity of oxygenation and haemodynamics in breast cancer resolved in vivo by conical multispectral optoacoustic mesoscopy.

2020 Proceedings of the National Academy of Sciences

Prakash J, Seyedebrahimi MM, Ghazaryan A, Najafabadi JM, Gujrati V, Ntziachristos V. Short-wavelength optoacoustic spectroscopy based on water muting.

2019 Biomedical Optics Express

Chen Z, Deán-Ben XL, Liu N, Gujrati V, Gottschalk S, Ntziachristos V, Razansky D. Concurrent fluorescence and volumetric optoacoustic tomography of nanoagent perfusion and bio-distribution in solid tumors.

2019 Nature Communications

Gujrati V, Prakash J, Najafabadi JM, Stiel AC, Klemm U, Mettenleiter G, Aichler M, Walch A, Ntziachristos V. Bioengineered bacterial vesicles as biological nano-heaters for optoacoustic imaging.

2019 Chemical Communications

Gujrati V, Mishra A, Ntziachristos V. Molecular imaging probes for multi-spectral optoacoustic tomography.

Nanomedicine & Biomarkers: Contact

Dr. Vipul Gujrati

Group Leader