The Biomin Research Group investigates biocrystallization processes in microalgae, particularly in dinoflagellates. We aim to understand how these single-celled organisms form highly ordered mineral structures and organic crystals such as calcium carbonate and guanine, and how these processes contribute to the cycling of elements in aquatic ecosystems.
To better understand the mechanisms of crystal formation and structural organization, we combine controlled cultivation experiments with modern spectroscopic and imaging methods. Furthermore, we use these biological structures as inspiration for the development of functional bio-based materials.
Biomineralization explores the formation of mineral structures by organisms, thus providing a central key to understanding the interactions between the biosphere and geosphere. It investigates the mechanisms by which living organisms produce inorganic-organic hybrid materials such as calcium carbonate or silicates to adapt to changing environmental conditions, form protective structures, or develop functional properties. Biominerals not only document biological processes but also serve as archives of past environmental and climatic conditions.
For approximately 500 million years, algae, in particular, have shaped our planet’s environment by sequestering CO₂ through the precipitation of minerals. These processes lead to an impressive diversity of complex architectures with exceptional morphological properties. A prominent example is the highly ordered, porous calcareous structures of single-celled dinoflagellates, whose regular organization cannot yet be reproduced with current technological methods. The study of such systems allows for the deciphering of fundamental principles of structural formation and, at the same time, provides insights into past environmental conditions.
While the biochemical foundations of biomineral formation in model organisms such as diatoms or coccolithophores are already comparatively well understood, the underlying mechanisms in dinoflagellates remain largely unclear. It is particularly noteworthy that mineral formation does not occur in strictly controlled intracellular compartments but in an extracellular space, the so-called outer matrix. This peculiarity makes dinoflagellates a promising model system – both for a fundamental understanding of biological structural formation and for the development of biomimetic materials. Biologically produced mesoporous structures represent a particularly attractive class of materials, as they combine complex functionality with high biocompatibility.
Biomineralization is thus at the center of an interdisciplinary research field that connects biology, chemistry, geosciences, and materials science. Through close collaborations with adjacent disciplines, a broad, analytically oriented, and application-focused research and teaching profile is created. Practical laboratory work forms an essential basis, especially in dealing with modern analytical procedures for characterizing biological systems and hydrated, amorphous substances.
Students who wish to specialize in this area acquire a profound understanding of the processes at the interface of animate and inanimate nature. This knowledge opens up diverse career prospects, for example, in environmental and climate research, material development, biogeochemical analytics, or academic research. Corresponding qualifications can be acquired within the geoscientific study programs (B.Sc. and M.Sc.) with appropriate specialization, as well as through a doctorate.
- The unusual genome of dinoflagellates: Sequencing of the calcifying microalga L. granifera)
- Raman spectroscopic analysis of biomass in speleothems: A spectral fingerprint of past changes in vegetation?
- DINOMAT (JA2659/3-1):
Understanding Biocrystallization in Dinoflagellates:
From Biological Pathways to Functionalized Hybrid Materials
- DinoLight (SAB 100503468):
Recruiting unicellular algae for the mass production of nano-structured perovskites
in collaboration with Prof. I. Zlotnikov and Prof. M. Schlierf, BCUBE Dresden
MSc and BSc Students
Alumni
- Dr. Amina Alizade (PhD student from 2021-2025)
X-ray Diffractometry
Many materials – from natural rocks to modern high-tech materials – consist of tiny crystals. Such structures are investigated using X-ray powder diffractometry (XRD or PXRD), a central method in geo- and materials sciences. It enables the identification and characterization of crystalline substances (phases) as well as their qualitative and quantitative determination and also allows conclusions to be drawn about the atomic structure.
Financed with support from Core4U 
Installation in Q3/2026
Contact Person: Jun.-Prof. Dr. A. Jantschke
Many materials – from natural rocks to modern high-tech materials – consist of tiny crystals. Such structures are investigated using X-ray powder diffractometry (XRD or PXRD), a central method in geo- and materials sciences. It enables the identification and characterization of crystalline substances (phases) as well as their qualitative and quantitative determination and also allows conclusions to be drawn about the atomic structure.
The Seifert X-ray diffractometer XRD 3000 TT for phase analysis of crystalline materials is designed as a full-protection device. The X-ray generator can be operated in the range of 2 to 60 kV and 2 to 80 mA (max. 3.5 KW). The goniometer in Bragg-Brentano geometry has an angular resolution of 0.0005° 2Θ and operates with a fixed sample holder. The device features an automatic divergence slit, a sample changer with sample rotation, and a secondary monochromator. A scintillation detector is used to record the X-ray reflections. For high resolution, a primary monochromator can be adapted.
Contact Persons: Jun.-Prof. Dr. A. Jantschke, Ralf Meffert
The XRD Mill McCrone was specifically developed for sample preparation in X-ray diffractometry. Its high efficiency is based on a unique grinding principle: 48 cylindrical grinding bodies are moved frictionally in a tumbling grinding bowl on a circular path, reducing the starting material from grain sizes < 0.5 mm to the lower micrometer range (typically < 10 µm). This results in short grinding times, minimal material loss, and a very narrow particle size distribution.
This gentle comminution leads to peak-shaped signals with a narrow half-width in the X-ray diffractogram, thus enabling precise phase analysis. At the same time, the crystal lattice structure is largely preserved, as hardly any crystal defects occur – a crucial prerequisite for meaningful XRD data.
The XRD Mill McCrone is suitable for both wet and dry grinding.
Contact Person: Jun.-Prof. Dr. A. Jantschke
Cell Culture Laboratory (photosynthetic microalgae)
In the Biomin Research Group, photosynthetic microalgae are cultivated in both marine and freshwater under controlled conditions, with a particular focus on dinoflagellates. The current collection includes 33 species cultivated in 10 media.
Taxonomically, dinoflagellates (13 strains) dominate, supplemented by diatoms (7), green algae (5), cryptophyceae (3), cyanobacteria (2), synurales (2), and haptophytes.
Contact Person: Jun.-Prof. Dr. A. Jantschke
The PLG 400 is a climate chamber for the controlled cultivation of plants and microorganisms under defined environmental conditions. Temperature, light intensity, and day/night cycles can be precisely adjusted to ensure reproducible growth conditions.
Contact Person: Jun.-Prof. Dr. A. Jantschke
For sterile work, an autoclave (Systec V-95) and a laminar flow workbench (SafeFAST Classic) are used. The autoclave enables the sterilization of media, solutions, and equipment using saturated steam under pressure. The sterile bench ensures a particle-free working environment through HEPA-filtered laminar flow, allowing cultures and samples to be processed under aseptic conditions.
Contact Person: Jun.-Prof. Dr. A. Jantschke
The Olympus IX70 is an inverted fluorescence microscope for examining samples in transmitted light and epifluorescence modes. Due to its inverted design, it is particularly suitable for the analysis of samples in liquids or cell cultures. The system features modular filter cubes for epifluorescence and the possibility to integrate polarization filters, allowing for the investigation of anisotropic material properties in addition to fluorescently labeled structures.
Contact Person: Jun.-Prof. Dr. A. Jantschke
The LUNA-FL is an automated fluorescence cell counter from Logos Biosystems for rapid and reproducible determination of cell count and cell viability. The system combines microscopic image acquisition with integrated software analysis and enables both brightfield and fluorescence measurements.
Contact Person: Jun.-Prof. Dr. A. Jantschke
The automatic titrator Mettler Toledo DL58 is a microprocessor-controlled analysis system for precise and reproducible execution of various titrations. It enables, among other things, potentiometric, photometric, amperometric, and pH-stat titrations and offers flexible method creation through freely programmable procedures.
In the Biomin Research Group, the system is used for the controlled synthesis of amorphous calcium carbonate (ACC) to precisely control reaction parameters such as pH value and titration rate. Through automated, incremental addition of reagents and continuous monitoring of the solution (e.g., pH or potential), supersaturation and nucleation can be specifically regulated, enabling reproducible and controlled ACC formation.
Contact Persons: Jun.-Prof. Dr. A. Jantschke, C. Liedgens
Cryo-Electron Microscopy
Cryo-electron microscopy (Cryo-EM) is a method for examining samples in a near-native state. Samples are shock-frozen so that water vitrifies, preserving the structure without dehydration or artifacts.
An important technique is the freeze-fracture method: Frozen samples are fractured, creating fracture surfaces along membranes or structural weak points. These surfaces can then be examined under the electron microscope, providing detailed insights into the organization of cell membranes and their proteins. Cryo-EM is therefore primarily used to analyze biological structures – especially membranes and large biomolecules – at high resolution.
At the Institute for Geosciences at JGU, all necessary equipment for Cryo-SEM analyses, including freeze-fracture, is available.
The Leica EM VCM (Vacuum Cryo Mounting) and the Leica EM VCT500 (Vacuum Cryo Transfer) together form a cryo-workflow system for electron microscopy: While the VCM serves as a workspace for preparing, loading, and manipulating samples under vacuum and cryogenic conditions, the VCT500 enables the subsequent contamination-free transfer of samples between preparation devices and the microscope, without interrupting the cryo and vacuum conditions.
Contact Person for Cryo-Preparation: Jun.-Prof. Dr. A. Jantschke
Cryo-electron microscopy (Cryo-EM) is a method for examining samples in a near-native state. Samples are shock-frozen so that water vitrifies, preserving the structure without dehydration or artifacts.
An important technique is the freeze-fracture method: Frozen samples are fractured, creating fracture surfaces along membranes or structural weak points. These surfaces can then be examined under the electron microscope, providing detailed insights into the organization of cell membranes and their proteins. Cryo-EM is therefore primarily used to analyze biological structures – especially membranes and large biomolecules – at high resolution.
At the Institute for Geosciences at JGU, all necessary equipment for Cryo-SEM analyses, including freeze-fracture, is available.
The Leica EM ACE600 is used for the deposition of ultrathin conductive layers (metal or carbon) on samples for SEM/TEM. In the cryo-configuration, it enables coating under cryogenic conditions, including cryo-stage, freeze-fracture option, and interface for cryo-transfer.
Contact Person for Cryo-Preparation: Jun.-Prof. Dr. A. Jantschke
Cryo-electron microscopy (Cryo-EM) is a method for examining samples in a near-native state. Samples are shock-frozen so that water vitrifies, preserving the structure without dehydration or artifacts.
An important technique is the freeze-fracture method: Frozen samples are fractured, creating fracture surfaces along membranes or structural weak points. These surfaces can then be examined under the electron microscope, providing detailed insights into the organization of cell membranes and their proteins. Cryo-EM is therefore primarily used to analyze biological structures – especially membranes and large biomolecules – at high resolution.
At the Institute for Geosciences at JGU, all necessary equipment for Cryo-SEM analyses, including freeze-fracture, is available.
The Leica EM TIC 3X is an ion beam preparation system that enables the precise production of cross-sections and surfaces using a triple ion beam. With the cryo-option (cooling stage down to approx. −160 °C and cryo-sample holder), temperature-sensitive or frozen samples can be prepared under cryogenic conditions, without structural changes or thawing.
Contact Person for Cryo-Preparation: Jun.-Prof. Dr. A. Jantschke
Cryo-electron microscopy (Cryo-EM) is a method for examining samples in a near-native state. Samples are shock-frozen so that water vitrifies, preserving the structure without dehydration or artifacts.
An important technique is the freeze-fracture method: Frozen samples are fractured, creating fracture surfaces along membranes or structural weak points. These surfaces can then be examined under the electron microscope, providing detailed insights into the organization of cell membranes and their proteins. Cryo-EM is therefore primarily used to analyze biological structures – especially membranes and large biomolecules – at high resolution.
At the Institute for Geosciences at JGU, all necessary equipment for Cryo-SEM analyses, including freeze-fracture, is available.
The Leica Slush Freezer generates a cold nitrogen “slush” phase to freeze (especially larger) samples very quickly and uniformly, thus preserving the native structure before further processing or analysis. With the help of the Leica Cryo Saw, frozen samples can be cut into defined cross-sections or smaller pieces without being damaged by warming or mechanical deformation – important for subsequent analysis in the electron microscope.
Contact Person for Cryo-Preparation: Jun.-Prof. Dr. A. Jantschke
Interested in BSc/MSc theses? Please contact us. Your own proposals are welcome.
ORCID: 0000-0003-1257-8830 / Google Scholar
