Nino Läubli

Last Name

Läubli

First Name

Nino

ORCID

0000-0003-2894-2385

Show all metadata

Search Results

Publications 1 - 10 of 19

A microrobotic system for simultaneous measurement of turgor pressure and cell-wall elasticity of individual growing plant cells
Burri, Jan T.; Vogler, Hannes; Munglani, Gautam; et al. (2019)
IEEE Robotics and Automation Letters
Neutrophil-inspired propulsion in a combined acoustic and magnetic field
Ahmed, Daniel; Baasch, Thierry; Blondel, Nicolas; et al. (2017)
Nature Communications
Systems capable of precise motion in the vasculature can offer exciting possibilities for applications in targeted therapeutics and non-invasive surgery. So far, the majority of the work analysed propulsion in a two-dimensional setting with limited controllability near boundaries. Here we show bio-inspired rolling motion by introducing superparamagnetic particles in magnetic and acoustic fields, inspired by a neutrophil rolling on a wall. The particles self-assemble due to dipole–dipole interaction in the presence of a rotating magnetic field. The aggregate migrates towards the wall of the channel due to the radiation force of an acoustic field. By combining both fields, we achieved a rolling-type motion along the boundaries. The use of both acoustic and magnetic fields has matured in clinical settings. The combination of both fields is capable of overcoming the limitations encountered by single actuation techniques. We believe our method will have far-reaching implications in targeted therapeutics.
3D mechanical characterization of single cells and small organisms using acoustic manipulation and force microscopy
Läubli, Nino; Burri, Jan T.; Marquard, Julian; et al. (2021)
Nature Communications
Quantitative micromechanical characterization of single cells and multicellular tissues or organisms is of fundamental importance to the study of cellular growth, morphogenesis, and cell-cell interactions. However, due to limited manipulation capabilities at the microscale, systems used for mechanical characterizations struggle to provide complete three-dimensional coverage of individual specimens. Here, we combine an acoustically driven manipulation device with a micro-force sensor to freely rotate biological samples and quantify mechanical properties at multiple regions of interest within a specimen. The versatility of this tool is demonstrated through the analysis of single Lilium longiflorum pollen grains, in combination with numerical simulations, and individual Caenorhabditis elegans nematodes. It reveals local variations in apparent stiffness for single specimens, providing previously inaccessible information and datasets on mechanical properties that serve as the basis for biophysical modelling and allow deeper insights into the biomechanics of these living systems.
High Aspect Ratio Nanoscale Pores through BCP-Based Metal Oxide Masks and Advanced Dry Etching
Paiva, Aislan Esmeraldo; Gerlt, Michael S.; Läubli, Nino; et al. (2023)
ACS Applied Materials & Interfaces
The reliable and regular modification of the surface properties of substrates plays a crucial role in material research and the development of functional surfaces. A key aspect of this is the development of the surface pores and topographies. These can confer specific advantages such as high surface area as well as specific functions such as hydrophobic properties. Here, we introduce a combination of nanoscale self-assembled block-copolymer-based metal oxide masks with optimized deep reactive ion etching (DRIE) of silicon to permit the fabrication of porous topographies with aspect ratios of up to 50. Following the evaluation of our procedure and involved parameters using various techniques, such as AFM or SEM, the suitability of our features for applications relying on high light absorption as well as efficient thermal management is explored and discussed in further detail.
Investigation of Cells and Organisms through Acoustic Manipulation
Läubli, Nino (2020)
Reduced Etch Lag and High Aspect Ratios by Deep Reactive Ion Etching (DRIE)
Gerlt, Michael S.; Läubli, Nino; Manser, Michel; et al. (2021)
Micromachines
Deep reactive ion etching (DRIE) with the Bosch process is one of the key procedures used to manufacture micron-sized structures for MEMS and microfluidic applications in silicon and, hence, of increasing importance for miniaturisation in biomedical research. While guaranteeing high aspect ratio structures and providing high design flexibility, the etching procedure suffers from reactive ion etching lag and often relies on complex oxide masks to enable deep etching. The reactive ion etching lag, leading to reduced etch depths for features exceeding an aspect ratio of 1:1, typically causes a height difference of above 10% for structures with aspect ratios ranging from 2.5:1 to 10:1, and, therefore, can significantly influence subsequent device functionality. In this work, we introduce an optimised two-step Bosch process that reduces the etch lag to below 1.5%. Furthermore, we demonstrate an improved three-step Bosch process, allowing the fabrication of structures with 6 µm width at depths up to 180 µm while maintaining their stability.
Feeling the force: how pollen tubes deal with obstacles
Burri, Jan T.; Vogler, Hannes; Läubli, Nino; et al. (2018)
New Phytologist
Fabrication of PDMS-based Acoustofluidic Devices for 3D Access to Single Cells and Small Organisms
Läubli, Nino; Nelson, Bradley (2021)
Protocol Exchange
Acoustofluidic manipulation has demonstrated significant potential for the investigation and handling of small organisms. In this protocol, we describe the steps required for the fabrication of a PDMS-based device with 150 um high structures to be used for the rotational manipulation of single cells and small organisms.
Mechanical factors contributing to the Venus flytrap's rate-dependent response to stimuli
Saikia, Eashan; Läubli, Nino; Vogler, Hannes; et al. (2021)
Biomechanics and Modeling in Mechanobiology
The sensory hairs of the Venus flytrap (Dionaea muscipula Ellis) detect mechanical stimuli imparted by their prey and fire bursts of electrical signals called action potentials (APs). APs are elicited when the hairs are sufficiently stimulated and two consecutive APs can trigger closure of the trap. Earlier experiments have identified thresholds for the relevant stimulus parameters, namely the angular displacement theta and angular velocity omega. However, these experiments could not trace the deformation of the trigger hair's sensory cells, which are known to transduce the mechanical stimulus. To understand the kinematics at the cellular level, we investigate the role of two relevant mechanical phenomena: viscoelasticity and intercellular fluid transport using a multi-scale numerical model of the sensory hair. We hypothesize that the combined influence of these two phenomena and omega contribute to the flytrap's rate-dependent response to stimuli. In this study, we firstly perform sustained deflection tests on the hair to estimate the viscoelastic material properties of the tissue. Thereafter, through simulations of hair deflection tests at different loading rates, we were able to establish a multi-scale kinematic link between omega and the cell wall stretch delta. Furthermore, we find that the rate at which delta evolves during a stimulus is also proportional to omega. This suggests that mechanosensitive ion channels, expected to be stretch-activated and localized in the plasma membrane of the sensory cells, could be additionally sensitive to the rate at which stretch is applied.
A single touch can provide sufficient mechanical stimulation to trigger Venus flytrap closure
Burri, Jan T.; Saikia, Eashan; Läubli, Nino; et al. (2020)
PLoS Biology
The carnivorous Venus flytrap catches prey by an ingenious snapping mechanism. Based on work over nearly 200 years, it has become generally accepted that two touches of the trap’s sensory hairs within 30 s, each one generating an action potential, are required to trigger closure of the trap. We developed an electromechanical model, which, however, suggests that under certain circumstances one touch is sufficient to generate two action potentials. Using a force-sensing microrobotic system, we precisely quantified the sensory-hair deflection parameters necessary to trigger trap closure and correlated them with the elicited action potentials in vivo. Our results confirm the model’s predictions, suggesting that the Venus flytrap may be adapted to a wider range of prey movements than previously assumed.

Publications 1 - 10 of 19

Nino Läubli

Last Name

First Name

ORCID

Organisational unit

Filters

Search Results