Daniel Havelka

Institute of Photonics and Electronics (IPE) | IPE · Bioelectrodynamics

Technologies based on pulsed electric field (PEF) are increasingly pervasive in medical and industrial applications. However, the detailed understanding of how PEF acts on biosamples including proteins at the molecular level is missing. There are indications that PEF might act on biomolecules via electrogenerated reactive oxygen species (ROS). Howe...

Pulsed electric field (PEF) technology is promising for the manipulation of biomolecular components and has potential applications in biomedicine and bionanotechnology. Microtubules, nanoscopic tubular structures self-assembled from protein tubulin, serve as important components in basic cellular processes as well as in engineered biomolecular nano...

Modulation of the structure and function of biomaterials is essential for advancing bio-nanotechnology and biomedicine. Microtubules (MTs) are self-assembled protein polymers that are essential for fundamental cellular processes and key model compounds for the design of active bio-nanomaterials. In this in silico study, a 0.5 μs-long all-atom molec...

Self-assembly is at the heart of many promising nanoscience technologies as well as at the core of life processes. Tubulin proteins self-assemble into microtubules, tube-like structures that are essential in cellular functions such as cell division and intracellular transport and also a major target in cancer therapies. Therefore, it is crucial to...

Remodeling of nanoscopic structures is not just crucial for cell biology, but it is also at the core of bioinspired materials. While the microtubule cytoskeleton in cells undergoes fast adaptation, adaptive materials still face this remodeling challenge. Moreover, the guided reorganization of the microtubule network and the correction of its abnorm...

Nanosecond pulsed electric field offers novel opportunities in bionanotechnology and biomedicine enabling ultrafast physical control of membrane, and protein‐based processes for the development of novel bionanomaterials and biomedical theranostic methods. However, the mechanisms of nanosecond pulsed electric field action at the nano‐ and molecular...

Microtubules are abundant natural subcellar nano-structures belonging to a class of cytoskeletal fibers responsible for key cell functions. In order to monitor the polymerization state of microtubules in vitro we developed a two-port wideband microfluidic chip based on coplanar waveguide transmission line with a narrows central conductor to provide...

Tubulin self‐assembly into microtubule is one of the most fascinating and inspiring processes in nature. In article number 1903636, Djamel Eddine Chafai, Michal Cifra, and co‐workers introduce a novel strategy based on nanosecond pulsed electric fields acting on the tubulin conformational state, leading to control over the self‐assembly process and...

Tubulin self‐assembly into microtubules is a fascinating natural phenomenon. Its importance is not just crucial for functional and structural biological processes, but it also serves as an inspiration for synthetic nanomaterial innovations. The modulation of the tubulin self‐assembly process without introducing additional chemical inhibitors/promot...

Intense pulsed electric fields are known to act at the cell membrane level and are already being exploited in biomedical and biotechnological applications. However, it is not clear if electric pulses within biomedically-attainable parameters could directly influence intra-cellular components such as cytoskeletal proteins. If so, a molecular mechani...

Intense pulsed electric fields are known to act at the cell membrane level and are already being exploited in biomedical and biotechnological applications. However, it is not clear if intra-cellular components such as cytoskeletal proteins could be directly influenced by electric pulses within biomedically-attainable parameters. If so, a molecular...

[This corrects the article DOI: 10.1371/journal.pone.0086501.].

To develop and reliably use diagnostic and therapeutic methods employing microwaves, we need to have an accurate knowledge of biological dielectric properties. Traditionally, dielectric properties of biosamples are determined experimentally. However, such measurements require dedicated hardware and physical availability of sufficient volume of biol...

Knowledge of electromagnetic properties of biomolecules is essential for a fundamental understanding of electric field interaction with biosystems and for development of novel biomedical diagnostic and therapeutic methods. To enable systematic analysis of the dielectric properties of biomolecule solutions we presented here a method for a rational d...

This roadmap outlines the role semiconductor-based materials play in understanding the complex biophysical dynamics at multiple length scales, as well as the design and implementation of next-generation electronic, optoelectronic, and mechanical devices for biointerfaces. The roadmap emphasizes the advantages of semiconductor building blocks in int...

The mechanical properties of microtubules are of great importance for understanding their biological function and for applications in artificial devices. Although microtubule mechanics has been extensively studied both theoretically and experimentally, the relation to its molecular structure is understood only partially. Here, we report on the stru...

There has been extensive study on the vibration dynamics and fluctuations of microtubules in the quest for understanding the relation between microtubule material properties and their ability to carry out several functions in cells. While experimental fluctuation analysis of microtubules has provided an important piece of knowledge about microtubul...

Guidelines for submitting commentsPolicy: Comments that contribute to the discussion of the article will be posted within approximately three business days. We do not accept anonymous comments. Please include your email address; the address will not be displayed in the posted comment. Cell Press Editors will screen the comments to ensure that they...

Electromagnetic activity of cells (>100 kHz) beyond the conventional frequency region of electrophysiology is poorly explored, yet it offers opportunities for new diagnostic and therapeutic methods in bioelectronic medicine and may provide insights into new general mechanism in cellular signalling. Here, we describe electromagnetic properties of mi...

Microtubules are known to be involved in intracellular signaling. Here, we show in silico that electrically polar collective vibration modes of microtubules form electric oscillating potential which is quasi-periodic both in space and in time. While single mode microtubule vibration excites an electric field with spatially stationary local minima a...

Paper deals with a description of research activities in the field of Microwave Medical Diagnostics and Treatment done at the Dept. of EM Field, Czech Technical University (CTU) in Prague. History of these activities goes to year 1981, when the first apparatus for microwave hyperthermia cancer treatment has been developed at CTU and one year later...

The regulation of chromosome separation during mitosis is not fully understood yet. Microtubules forming mitotic spindles are targets of treatment strategies which are aimed at (i) the triggering of the apoptosis or (ii) the interruption of uncontrolled cell division. Despite these facts, only few physical models relating to the dynamics of mitotic...

Physical processes in living cells were not taken into consideration among the essentials of biological activity, regardless of the fact that they establish a state far from thermodynamic equilibrium. In biological system chemical energy is transformed into the work of physical forces for various biological functions. The energy transformation path...

Spontaneous mechanical oscillations were predicted and experimentally proven on almost every level of cellular structure. Besides morphogenetic potential of oscillatory mechanical force, oscillations may drive vibrations of electrically polar structures or these structures themselves may oscillate on their own natural frequencies. Vibrations of ele...

Field of microwave applications is expanding very rapidly and it already encompasses very wide spectrum of common and well developed medical and industrial procedures. It is very important for further research that there are reliable means of analyzing effects of electromagnetic field on various materials in real-time. In this paper we present our...

The cytoskeleton, especially microtubules, is potential source of electrodynamic field of living eukaryote cells. Microtubule network is a very dynamic structure which is composed of highly polar molecules - tubulin heterodimers. Microtubules have their eigenmode vibrations in frequency range from kHz to GHz. We approximated electrical properties o...

Microtubules are electrically polar structures fulfilling prerequisites for generation of oscillatory electric field in the kHz to GHz region. Energy supply for excitation of elasto-electrical vibrations in microtubules may be provided from GTP-hydrolysis; motor protein-microtubule interactions; and energy efflux from mitochondria. It recently was...

Microtubules are important structures in the cytoskeleton, which organizes the cell. Since microtubules are electrically polar, certain microtubule normal vibration modes efficiently generate oscillating electric field. This oscillating field may be important for the intracellular organization and intercellular interaction. There are experiments wh...

Medical applications of microwaves (i.e., a possibility to use microwave energy and/or microwave technique and technology for therapeutical purposes) are a quite new and a very rapidly developing field. Microwave thermotherapy is being used in medicine for the cancer treatment and treatment of some other diseases since early eighties. In this contr...

Microtubules are important organizing structures of eukaroytic cells. They are electrically polar and have collective vibration modes from kHz to low THz region. In approximation of microtubule subunits (tubulin molecules) as rigid particles, we calculate electric field generated by optical branch of axial longitudinal vibration modes of microtubul...

Certain structures in a living cell may generate electric oscillations. Microtubules, which form a part of a cellular skeleton, belong to this class of structures and fulfill all conditions for generation of electric oscillations in kHz÷GHz band. We present selected results from calculations of the oscillatory electric field generated by higher vib...

Microtubules are electrically polar structures fulfilling prerequisites for generation of oscillatory electric field in the kHz to GHz region. Energy supply for excitation of elasto-electrical vibrations in microtubules may be provided from GTP-hydrolysis; motor protein-microtubule interactions; and energy efflux from mitochondria. We calculated el...

Microtubules are important structures in cytoskeleton which organizes the cell. Single microtubule is composed of electrically polar structures, tubulin heterodimers, which have strong electric dipole moment. Vibrations are expected to be generated in microtubules, thus tubulin heterodimers as electric dipoles are oscillating. This gives rise to el...

Under physiological conditions, supramolecular biological structures undergo nanoscale mechanical vibrations. Since proteins, which form building units of these structures, are usually highly electrically polar, mechanical oscillations will be accompanied by oscillating electric field. However, molecular modeling methods are not yet able to perform...