ZAWACKA PROGRAMME – Dr. Karolina Zajdel

NAWA Zawacka Programme – Outgoing Mobility Call 2026/2027 – China

The programme supports international academic mobility and the development of research cooperation between Poland and partner countries.

As part of the programme, the applicant will undertake a four-month research internship at Tongji University, China, under the supervision of Prof. Dr. Zhenyue Chen at the Institute of Precision Optical Engineering Technology, School of Physics and Engineering.

The aim of the proposed research stay is to develop and investigate luminescent upconversion nanoparticles (UCNPs) for applications in innovative multimodal biomedical imaging. The project will focus on the rational design, synthesis, and surface functionalization of UCNP-based nanoplatforms, together with their implementation in advanced photoacoustic imaging (PAI) systems.

Upconversion nanoparticles constitute an emerging class of luminescent nanomaterials capable of converting near-infrared (NIR) excitation into higher-energy visible (VIS) or ultraviolet (UV) emission through nonlinear optical processes. This unique optical behaviour enables deep-tissue excitation with minimal autofluorescence and reduced photodamage, making UCNPs highly suitable for biological imaging. Their low cytotoxicity, excellent photostability, and resistance to photobleaching further enhance their potential as robust imaging probes.

Additionally, UCNPs exhibit natural luminescence which, when combined with photoacoustic imaging, enables dual-modality imaging and allows mutual validation of signals obtained from different imaging techniques. The ease of nanoparticle surface functionalization further expands their application potential by enabling the conjugation of targeting ligands, such as antibodies or peptides, for precise subcellular imaging and theranostic applications.

These characteristics make UCNPs particularly valuable in preclinical studies, where they have been successfully applied in tumour imaging, vascular mapping, and monitoring of drug delivery in animal models. Photoacoustic imaging combines the advantages of optical excitation and ultrasonic detection, enabling highly sensitive visualization of optical probes through the detection of ultrasound waves generated by pulsed laser irradiation.

Owing to these properties, UCNPs represent a promising class of contrast agents for photoacoustic imaging. Compared with conventional organic dyes and metallic nanostructures, UCNP-based systems offer improved optical tunability, enhanced stability, and multifunctionality. Their integration with photoacoustic imaging enables the development of dual-modal platforms that combine the high sensitivity of optical methods with the superior spatial resolution and penetration depth of acoustic detection.

The choice of Tongji University as the host institution is motivated by its internationally recognized expertise in biomedical imaging and nanotechnology. The research group led by Prof. Chen is actively engaged in the development of innovative photoacoustic imaging technologies and multimodal imaging systems and provides access to advanced instrumentation and specialized infrastructure that are not available at the applicant’s home institution.

The integration of expertise in UCNP synthesis and functionalization with state-of-the-art photoacoustic imaging technologies represents a highly innovative research direction. This collaboration will enable the development of advanced UCNP-based nanoplatforms for biomedical imaging with enhanced sensitivity, specificity, and multifunctionality.

To date, only a limited number of studies have explored the application of UCNPs in photoacoustic imaging, particularly in the context of neuroimaging and related biomedical applications. Therefore, the proposed research addresses an important gap in the current state of the art and has the potential to contribute significantly to the advancement of multimodal imaging technologies.

The project supports the development of luminescent UCNPs as advanced nanosensors for multimodal biomedical imaging. The application of UCNPs in PAI will enable the development of more sensitive and precise diagnostic tools. Properly designed, safe, and photostable nanoplatforms have the potential to improve the quality of imaging diagnostics, reduce the invasiveness of procedures, and facilitate earlier detection of pathological changes in patients.

Submission deadline 29.01.2026; accepted on 14.07.2026.

Budget for 4 months: 18 000 PLN

Time frame: 15.02.2027 – 15.06.2027

Link to the website:

https://nawa.gov.pl/en/international-cooperation-and-exchange/zawacka-nawa