scholarly journals Fibroblasts Accelerate Formation and Improve Reproducibility of 3D Cellular Structures Printed with Magnetic Assistance

Research ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Sarah Mishriki ◽  
Srivatsa Aithal ◽  
Tamaghna Gupta ◽  
Rakesh P. Sahu ◽  
Fei Geng ◽  
...  
Keyword(s):  
Cellular Structures ◽  
Gravitational Settling ◽  
Lab On Chip ◽  
A Cell ◽  
Paramagnetic Salt ◽  
On Chip ◽  
Nih 3T3 ◽  
Cell Medium ◽  
3D Cellular Structures

Fibroblasts (mouse, NIH/3T3) are combined with MDA-MB-231 cells to accelerate the formation and improve the reproducibility of 3D cellular structures printed with magnetic assistance. Fibroblasts and MDA-MB-231 cells are cocultured to produce 12.5 : 87.5, 25 : 75, and 50 : 50 total population mixtures. These mixtures are suspended in a cell medium containing a paramagnetic salt, Gd-DTPA, which increases the magnetic susceptibility of the medium with respect to the cells. A 3D monotypic MDA-MB-231 cellular structure is printed within 24 hours with magnetic assistance, whereas it takes 48 hours to form a similar structure through gravitational settling alone. The maximum projected areas and circularities, and cellular ATP levels of the printed structures are measured for 336 hours. Increasing the relative amounts of the fibroblasts mixed with the MDA-MB-231 cells decreases the time taken to form the structures and improves their reproducibility. Structures produced through gravitational settling have larger maximum projected areas and cellular ATP, but are deemed less reproducible. The distribution of individual cell lines in the cocultured 3D cellular structures shows that printing with magnetic assistance yields 3D cellular structures that resemble in vivo tumors more closely than those formed through gravitational settling. The results validate our hypothesis that (1) fibroblasts act as a “glue” that supports the formation of 3D cellular structures, and (2) the structures are produced more rapidly and with greater reproducibility with magnetically assisted printing than through gravitational settling alone. Printing of 3D cellular structures with magnetic assistance has applications relevant to drug discovery, lab-on-chip devices, and tissue engineering.

PDMS Surface Modification Using Biomachining Method for Biomedical Application

2016 ◽  
Vol 26 ◽  
pp. 66-72 ◽  
Author(s):  
Yudan Whulanza ◽  
Hanif Nadhif ◽  
Jos Istiyanto ◽  
Sugeng Supriadi ◽  
Boy Bachtiar
Keyword(s):  
Surface Roughness ◽  
Surface Modification ◽  
Cell Attachment ◽  
Biomedical Application ◽  
Hydrophobic Surface ◽  
Polydimethyl Siloxane ◽  
Lab On Chip ◽  
Pdms Surface ◽  
A Cell ◽  
On Chip

Engineering a cell-friendly material in a form of lab-on-chip is the main goal of this study. The chip was made of polydimethyl siloxane (PDMS) with a surface modification to realize a groovy structure on its surface. This groovy surface was naturally and randomly designed via biomachining process. This measure was aimed to improve the cell attachment on the PDMS surface that always known as hydrophobic surface. The biomachined surface of mold and also products were characterized as surface roughness and wettability. The result shows that the biomachining process were able to be characterized in three classes of roughness on the surface of PDMS.

scholarly journals Organ on a Chip (Kidney)

2019 ◽  
Vol 8 (12) ◽  
pp. 1424-1426
Keyword(s):  
Power Management ◽  
Porous Membrane ◽  
Artificial Organ ◽  
Silicon Membrane ◽  
Lab On Chip ◽  
Analog Part ◽  
Organ On A Chip ◽  
On Chip ◽  
Different Thickness

Organ on a chip (OOC) is called an artificial organ, and it is a multi-channel the purpose of the chip is to absence in vivo the chip consists of both digital and analog part digital part mainly dedicated to the communication protocol, it also includes power management with clock switches; silicon is a promising material due to its reliable and required features for making porous silicon membrane. OOC deals with the precise bioMEMS. Porous membrane is used in so many applications mostly in Biomes’, lab on chip and mems. This paper explains the effect of pressure through the silicon membrane based on the deflection different thickness of membranes and pore shapes in various levels of pressure applied on silicon membrane. 10nm thin silicon membrane was studied to be far superior to the 25nm silicon thin membrane being able to automatically survive the applied force up to 7-33kpa (55mhg)

scholarly journals A novel hanging spherical drop system for the generation of cellular spheroids and high throughput combinatorial drug screening

2015 ◽  
Vol 3 (4) ◽  
pp. 581-585 ◽  
Author(s):  
A. I. Neto ◽  
C. R. Correia ◽  
M. B. Oliveira ◽  
M. I. Rial-Hermida ◽  
C. Alvarez-Lorenzo ◽  
...  
Keyword(s):  
High Throughput ◽  
Drug Screening ◽  
Spherical Drop ◽  
Lab On Chip ◽  
Cellular Spheroids ◽  
On Chip ◽  
High Throughput Manner

A novel hanging spherical drop system based on the use of biomimetic superhydrophobic flat substrates allows one to generate arrays of independent spheroid bodies in a high throughput manner, in order to mimic in vivo tumour models on the lab-on-chip scale.

scholarly journals Electrophysiology Read-Out Tools for Brain-on-Chip Biotechnology

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 124
Author(s):  
Csaba Forro ◽  
Davide Caron ◽  
Gian Angotzi ◽  
Vincenzo Gallo ◽  
Luca Berdondini ◽  
...  
Keyword(s):  
Cell Biology ◽  
Brain Activity ◽  
Pharmaceutical Research ◽  
Brain Structures ◽  
Cell Culture Techniques ◽  
Lab On Chip ◽  
Culture Techniques ◽  
On Chip

Brain-on-Chip (BoC) biotechnology is emerging as a promising tool for biomedical and pharmaceutical research applied to the neurosciences. At the convergence between lab-on-chip and cell biology, BoC couples in vitro three-dimensional brain-like systems to an engineered microfluidics platform designed to provide an in vivo-like extrinsic microenvironment with the aim of replicating tissue- or organ-level physiological functions. BoC therefore offers the advantage of an in vitro reproduction of brain structures that is more faithful to the native correlate than what is obtained with conventional cell culture techniques. As brain function ultimately results in the generation of electrical signals, electrophysiology techniques are paramount for studying brain activity in health and disease. However, as BoC is still in its infancy, the availability of combined BoC–electrophysiology platforms is still limited. Here, we summarize the available biological substrates for BoC, starting with a historical perspective. We then describe the available tools enabling BoC electrophysiology studies, detailing their fabrication process and technical features, along with their advantages and limitations. We discuss the current and future applications of BoC electrophysiology, also expanding to complementary approaches. We conclude with an evaluation of the potential translational applications and prospective technology developments.

scholarly journals Estimation Algorithm for a Hybrid PDE–ODE Model Inspired by Immunocompetent Cancer-on-Chip Experiment

Axioms ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 243
Author(s):  
Gabriella Bretti ◽  
Adele De De Ninno ◽  
Roberto Natalini ◽  
Daniele Peri ◽  
Nicole Roselli
Keyword(s):  
Immune Cells ◽  
Immune Cell ◽  
Spline Interpolation ◽  
Estimation Algorithm ◽  
Model Parameters ◽  
Ode Model ◽  
Lab On Chip ◽  
Chip Experiment ◽  
On Chip

The present work is motivated by the development of a mathematical model mimicking the mechanisms observed in lab-on-chip experiments, made to reproduce on microfluidic chips the in vivo reality. Here we consider the Cancer-on-Chip experiment where tumor cells are treated with chemotherapy drug and secrete chemical signals in the environment attracting multiple immune cell species. The in silico model here proposed goes towards the construction of a “digital twin” of the experimental immune cells in the chip environment to better understand the complex mechanisms of immunosurveillance. To this aim, we develop a tumor-immune microfluidic hybrid PDE–ODE model to describe the concentration of chemicals in the Cancer-on-Chip environment and immune cells migration. The development of a trustable simulation algorithm, able to reproduce the immunocompetent dynamics observed in the chip, requires an efficient tool for the calibration of the model parameters. In this respect, the present paper represents a first methodological work to test the feasibility and the soundness of the calibration technique here proposed, based on a multidimensional spline interpolation technique for the time-varying velocity field surfaces obtained from cell trajectories.

Digital nanoliter to milliliter flow rate sensor with in vivo demonstration for continuous sweat rate measurement

Lab on a Chip ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 178-185 ◽  
Author(s):  
Jessica Francis ◽  
Isaac Stamper ◽  
Jason Heikenfeld ◽  
Eliot F. Gomez
Keyword(s):  
Dynamic Range ◽  
Limit Of Detection ◽  
Sweat Rate ◽  
Rate Measurement ◽  
Wide Dynamic Range ◽  
Lab On Chip ◽  
Sensing Systems ◽  
On Chip ◽  
Rate Sensor

A digital flowmetry sensor is fabricated with low limit of detection and wide dynamic range, that is suitable for lab-on-chip or wearable sweat sensing systems.

scholarly journals Novel Fabrication Approach of a Porous Silicon Biocompatible Membrane Evaluated within a Alveolar Coculture Model

2021 ◽  
Author(s):  
Marcus A. C. Williams ◽  
Cooper Wiens ◽  
Adam Hamilton ◽  
Sophie Mancha ◽  
Madeline Stalder ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Gas Exchange ◽  
Model Systems ◽  
Human Anatomy ◽  
Blood Gas ◽  
Lab On Chip ◽  
Chip Technology ◽  
On Chip ◽  
Tissue Interfaces

The use of conventional in vitro and preclinical animal models often fail to properly recapitulate the complex nature of human diseases and hamper the success of translational therapies in humans [1-3] Consequently, research has moved towards organ-on-chip technology to better mimic human tissue interfaces and organ functionality. Herein, we describe a novel approach for the fabrication of a biocompatible membrane made of porous silicon (PSi) for use in organ-on-chip technology that provides key advantages when modeling complex tissue interfaces seen in vivo. By combining well-established methods in the semiconductor industry with organ-on-chip technology, we have developed a novel way of producing thin (25 μm) freestanding PSi biocompatible membranes with both nano (~15.5 nm diameter pores) and macroporous (~0.5 μm diameter pores) structures. To validate the proposed novel membrane, we chose to recapitulate the dynamic environment of the alveolar blood gas exchange interface in alveolar co-culture. Viability assays and immunofluorescence imaging indicate that human pulmonary cells remain viable on the PSi membrane during long-term culture (14 days). Interestingly, it was observed that macrophages can significantly remodel and degrade the PSi membrane substrate in culture. This degradation will allow for more intimate physiological cellular contact between cells, mimicking a true blood-gas exchange interface as observed in vivo. Broadly, we believe that this novel PSi membrane may be used in more complex organ-on-chip and lab-on-chip model systems to accurately recapitulate human anatomy and physiology to provide further insight into human disease pathology and pre-clinical response to therapeutics.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

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