document

Acoustic Fresnel lens to focus ultrasound for in vitro neuromodulation

Savundranayagam, Reka (author)

In vitro neuromodulation studies play a crucial role in understanding the underlying interaction mechanisms between cells and ultrasound, which is important in the development of new therapies for various neurological disorders. Acoustic focusing, the ability to focus ultrasound at a specific focal length with high spatial resolution, provides a...

master thesis 2023

document

Manufacturing of the fully inkjet-printed dielectric elastomer actuator

Wu, Yantong (author)

This thesis aims to solve the problems and fabricate fully inkjet-printed dielectric elastomer actuators with silver electrodes and a PDMS middle layer. First, a conductive silver electrode is printed on a coated PET substrate, followed by a printing of the dielectric elastomer middle layer to cover the bottom electrode. Then, the top silver...

master thesis 2022

document

Characterization and Processing of Elastomers for Organ-on-Chip Applications

Schoonhoven, Jilian (author)

The current standard for organ-on-chip substrate materials is polydimethylsiloxane (PDMS). PDMS has many beneficial properties such as biocompatibility, transparency, elasticity, and easy prototyping. The main disadvantages of PDMS are its hydrophobicity (reducing cell attachment and cell proliferation), quick hydrophobic recovery (within a few...

master thesis 2022

document

Rapid Prototyping of Organ-on-a-Chip Devices Using Maskless Photolithography

Kasi, D.G. (author), de Graaf, M.N.S. (author), Motreuil-Ragot, P.A. (author), Frimat, Jean-Phillipe M. S. (author), Ferrari, Michel D. (author), Sarro, Pasqualina M (author), Mastrangeli, Massimo (author), van den Maagdenberg, Arn M.J.M. (author), Mummery, Christine (author), Orlova, Valeria (author)

Organ-on-a-chip (OoC) and microfluidic devices are conventionally produced using microfabrication procedures that require cleanrooms, silicon wafers, and photomasks. The prototyping stage often requires multiple iterations of design steps. A simplified prototyping process could therefore offer major advantages. Here, we describe a rapid and...

journal article 2022

document

High-Frequency Surface Dynamics at an Electroactive Polymer Producing Underwater Soundwaves

Visschers, Fabian L.L. (author), Massaad Mouawad, J.M. (author), van Neer, P.L.M.J. (author), Verweij, M.D. (author), Liu, Danqing (author), Broer, Dirk J. (author)

Coatings with dynamic surface structures are appealing to many applications like haptics and soft robotics. Restrictively, the speed of the surface dynamics in these coatings is often limited to frequencies below 1 kHz, which makes them unsuitable for applications like acoustics and communication optics. This work describes a method to create...

journal article 2022

document

Inkjet printing of a low actuation voltage dielectric elastomer actuator

Elschot, Sanne (author)

Dielectric elastomer actuators (DEAs) are a type of soft actuators that consist of a dielectric elastomer membrane, covered with an electrode on the top and the bottom. When applying a potential, the opposite charges on the electrodes induce an electrostatic force which squeezes the elastomer, causing it to expand. This expansion can be used as...

master thesis 2021

document

Low-cost Benchtop Equipment and Procedures for Organ-on-Chip Prototyping

Aalbers, Sarah (author)

The Organ on Chip (OoC) market is fast-growing and has the promise to drastically reduce the cost of developing drugs and the need for animal testing. However, the growth could be obstructed by the difficulties of scaling up production of developed prototypes. Most OoC prototypes are not suited for mass production because of the material used,...

master thesis 2021

document

MEMS Solutions For More Than Illumination

Li, X. (author)

The development of solid state lighting (SSL) has been involving with improving the luminaire efficiency and integrating non-luminous functions, also known as More than Illumination. The objective of this thesis is to investigate different solutions for the concept of More than Illumination for SSL applications, to combine general lighting with...

doctoral thesis 2020

document

Towards a Microfabricated Flexible Graphene-Based Active Implant for Tissue Monitoring During Optogenetic Spinal Cord Stimulation

Velea, A. (author), Vollebregt, S. (author), Hosman, T.B. (author), Pak, A. (author), Giagka, Vasiliki (author)

This work aims to develop a smart neural interface with transparent electrodes to allow for electrical monitoring of the site of interest during optogenetic stimulation of the spinal cord. In this paper, a microfabrication process for the wafer-level development of such a compact, active, transparent and flexible implant is presented. Graphene...

conference paper 2020

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Long-term encapsulation of platinum metallization using a HfO2 ALD - PDMS bilayer for non-hermetic active implants

Nanbakhsh, K. (author), Ritasalo, R. (author), Serdijn, W.A. (author), Giagka, Vasiliki (author)

In this work, we investigate the insulating performance of an atomic layer deposited (ALD) HfO2 - polymer bilayer for platinum (Pt) metallization. As test vehicles, Pt interdigitated comb structures (IDC) were designed and fabricated on SiO2/Si substrates. The IDCs were first coated with a 100 nm thin HfO2 ALD layer. A group of samples was...

conference paper 2020

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Low-Impedance PEDOT:PSS MEA Integrated in a Stretchable Organ-on-Chip Device

Waafi, Affan K. (author), Gaio, N. (author), Quiros Solano, W.F. (author), Dijkstra, Paul (author), Sarro, Pasqualina M (author), Dekker, R. (author)

We present the first Organ-on-Chip equipped with a low-impedance Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) MicroElectrode Array (MEA). The novel device allows simultaneous mechanical stimulation with a stretchable PDMS membrane and electrical monitoring via the PEDOT:PSS MEA of multiple in vitro cell cultures. The...

journal article 2020

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Design and Fabrication of a Dielectric Elastomer Actuator for Organ-on-Chips Platforms

Zhang, Chuqian (author)

Cell behavior in vitro can be regulated by mechanical stimulation. Cytostretch is an Organ-on-Chip (OOC) platform that allows cyclic stretching tissue in culture. Its pneumatic actuation can hinder it from microfluidic systems integration. A dielectric elastomer actuator (DEA) was developed and fabricated in this thesis for Cytostretch as an...

master thesis 2019

document

Monolithic integration of silicon and polymer microstructures for Organ-on-Chip applications

Quiros Solano, W.F. (author)

Drug development is a complex, time-consuming (10 - 15 years) and expensive process. For a new medicine to reach the market, the net expenses covered by the pharmaceutical industry have been estimated to be around $2.6 billion. Nevertheless, the risk of finding adverse effects or toxicity cases once the drug is already on the market is still...

doctoral thesis 2019

document

Optimization of microporous PDMS membranes for Organ-on-Chip devices

Kootte, Bart (author)

Organ-on-chip (OOC) devices are micro-engineered three-dimensional (3D) biomimetic systems that can be used to create in vitro models of human tissue. They provide an alternative for conventional cell culture tools in pharmaceutical R&D. Moreover, these devices can contribute in research focused on understanding complex disease processes....

master thesis 2019

document

Inverted pyramidally-textured PDMS antireflective foils for perovskite/silicon tandem solar cells with flat top cell

Hou, Fuhua (author), Han, C. (author), Isabella, O. (author), Yan, Lingling (author), Shi, Biao (author), Chen, Junfan (author), An, Sichong (author), Zeman, M. (author)

Perovskite/silicon tandem solar cells (TSCs) have the potential to achieve power conversion efficiency exceeding 30%. To be compatible with high-efficiency solution-deposited perovskite top cell, a planar front surface for silicon bottom cell is generally required. However, flat front surfaces result in large light reflection losses and thus...

journal article 2019

document

Metal and Polymeric Strain Gauges for Si-based, Monolithically Fabricated Organs-on-Chips

Quiros Solano, W.F. (author), Gaio, N. (author), Silvestri, C. (author), Pandraud, G. (author), Dekker, R. (author), Sarro, Pasqualina M (author)

Organ-on-chip (OOC) is becoming the alternative tool to conventional in vitro screening. Heart-on-chip devices including microstructures for mechanical and electrical stimulation have been demonstrated to be advantageous to study structural organization and maturation of heart cells. This paper presents the development of metal and polymeric...

journal article 2019

document

PDMS Microlenses for Focusing Light in Narrow Band Imaging Diagnostics

Costa, Adriana C. (author), Pimenta, Sara (author), Ribeiro, João F. (author), Silva, Manuel F. (author), Wolffenbuttel, R.F. (author), Dong, Tao (author), Yang, Zhaochu (author), Correia, José H. (author)

Minimally invasive medical devices can greatly benefit from Narrow Band Imaging (NBI) diagnostic capabilities, as different wavelengths allow penetration of distinct layers of the gastrointestinal tract mucosa, improving diagnostic accuracy and targeting different pathologies. An important performance parameter is the light intensity at a...

journal article 2019

document

Compliant Fluidic Control Structures: Concept and synthesis approach

Kumar, P. (author), Fanzio, P. (author), Sasso, L. (author), Langelaar, M. (author)

The concept and synthesis approach for planar Compliant Fluidic Control Structures (CFCSs), monolithic flexible continua with embedded functional pores, is presented in this manuscript. Such structures are envisioned to find application in biomedicine as tunable microfluidic devices for drug/nutrient delivery. The functional pores enlarge and...

journal article 2019

document

A CMOS process compatible charge-modulated FGFET based ion sensor for integration into Organ-on-Chip platforms

Sinha, Rajarshi (author)

Drug development is an entire area of research that partly exploits the developments from biomedical research. Understanding the diseases that affect humanity fatally is critical to our existence. Researchers have studied various molecules and genetic compounds that are responsible for the proliferation of these diseases in the human body. For...

master thesis 2018

document

Free standing interconnects for stretchable electronics

Joshi, S. (author)

Advancements in stretchable electronic systems have changed the way modern electronics interact with their target systems, by their conformability to more complex shapes as compared to conventional rigid or flexible electronics. By utilizing this, limitless applications in the field of healthcare can be realized, such as wearable and implantable...

doctoral thesis 2018