Cooperations

Department of Biophysics

Research

The Biophysics Department conducts interdisciplinary research at the interface of biomolecular function, physical chemistry and radiochemistry. The activities contribute to the Helmholtz Research Programmes Nuclear Safety and Cancer Research in the Helmholtz-Association. We are member of the Cluster of Excellence "Physics of Life" (PoL) in Dresden.

We are particularly interested in:

structural and dynamic aspects of biomembranes
conformational transitions in membrane proteins
interactions between (radio)metals and biomolecules
effects of metals and radionuclides on the metabolism of microorganisms (Televised MDR report)

Education

The Biophysics department participates in the Dresden International Graduate School for Biomedicine and Bioengineering (DIGS-BB) supported by the Excellence Initiative of the German federal and state governments.

Practicals on Molecular Spectroscopy and Calorimetry are offered. The following lectures are held at the technische Universität Dresden and are elgible for the Master Specialization "Soft Condensed Matter and Biological Physics":

Biological Thermodynamics (English, summer semester)
Biophysical Methods (German, winter semester)

Seminar lectures for the International BIOTEC-Master Programme,

Vibrational Spectroscopy (English)
Absorption and Fluorescence Spectroscopy (English)

Experimental Methods

Fourier transform infrared spectroscopy
Circular dichroism
Static and time-resolved fluorescence spectroscopy
Calorimetry
Mass-Spectroscopy

Spectroscopic data are evaluated in combination with Density Functional Theory to understand photochemoical and photophysical properties of organic complexes of actinides.

Latest publication

Macrocyclic and Hydroxamate Ligands for ²²⁵Ac Radiopharmaceuticals: Evaluating SSTR2-Targeting Potential

Tsushima, S.; Seal, A.; Samsonov, S. A.; Fahmy, K.; Takao, K.

Abstract

The development of effective radiopharmaceuticals requires careful consideration of chelator properties and their impact on target receptor interactions. This study comprehensively investigated the molecular interactions between various 225Ac radiopharmaceuticals, differing in chelator structure, and somatostatin receptor 2 (SSTR2). The results indicate that 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetra(methylene)phosphonic acid (DOTP) represents a promising alternative to the commonly used 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), likely due to its higher negative charge. Incorporation of a polyethylene glycol linker (PEG4) between the chelator and the peptide moiety of the ligand significantly enhanced receptor activation. Density functional theory calculations identified hydroxamate ligands as potential alternatives to macrocyclic chelators, prompting the synthesis and characterization of a siderophore ligand, N1-[5-(Acetylhydroxyamino)pentyl]-N26-(5-aminopentyl)-N26,5,16-trihydroxy-4,12,15,23-tetraoxo-5,11,16,22-tetraazahexacosanediamide (DFO*), and its complexation with La3+ (a model for Ac3+) was confirmed by 1H and 139La NMR spectroscopy. While DFO* demonstrated high chelating ability and receptor recognition, its flexibility induced significant fluctuations atop the receptor. In contrast, the deoxy variant of the well-studied 3,4,3-LI(1,2-HOPO) ligand was identified as a structurally suitable chelating agent for 225Ac radiopharmaceuticals.

Inorganic Chemistry 65(2026)14, 7592-7602
DOI: 10.1021/acs.inorgchem.5c04349

Permalink: https://www.hzdr.de/publications/Publ-42125

More publications

Team

Name	Bld./Office	+49 351 260	Email
Head
Prof. Dr. Karim Fahmy	801/P301	2952 3601	k.fahmyhzdr.de
Employees
Name	Bld./Office	+49 351 260	Email
Dr. Björn Drobot	801/P302	2978	b.drobothzdr.de
Prof. Dr. Satoru Tsushima	801/P302	2978	s.tsushimahzdr.de
Other employees
Name	Bld./Office	+49 351 260	Email
Dr. Charlotte Kielar	801/P303	3247 3892	c.kielarhzdr.de

Physical Chemistry of Biomolecular Condensates

Name	Bld./Office	+49 351 260	Email
Head
Dr. Ellen Adams	801/P301	2911	e.adamshzdr.de
Employees
Name	Bld./Office	+49 351 260	Email
Likhitha Chakra Priya Pulibandla	801/P303	3375	l.pulibandlahzdr.de
Manthan Raj	801/P303	3375	m.rajhzdr.de