A Low-Cost, Rapidly Integrated Debubbler (RID) Module for Microfluidic Cell Culture Applications

AbstractMicrofluidic platforms use controlled fluid flow to provide physiologically relevant biochemical and biophysical cues to cultured cells in a well-defined and reproducible manner. In these systems, undisturbed flows are critical and air bubbles entering microfluidic channels can result in device delamination or cell damage. To prevent bubble entry, we report a low-cost, Rapidly Integrated Debubbler (RID) module that is simple to fabricate, inexpensive, and easily combined with existing experimental systems. We demonstrate successful removal of air bubbles spanning three orders of magnitude with a maximum removal rate (dV/dt)max = 1.5 mL min−1, at flow rates corresponding to physiological fluid-induced wall shear stresses (WSS) needed for biophysical stimulation studies on cultured mammalian cell populations.

Download Full-text

Piezoresistive Conductive Microfluidic Membranes for Low-Cost On-Chip Pressure and Flow Sensing

10.20944/preprints202112.0410.v1 ◽

2021 ◽

Author(s):

Md Nazibul Islam ◽

Steven M Doria ◽

Zachary R Gagnon

Keyword(s):

Time Pressure ◽

Low Cost ◽

Fluid Pressure ◽

Fluid Flows ◽

Microfluidic Devices ◽

Microfluidic Channels ◽

Impedance Change ◽

Conductive Membranes ◽

Chip Fabrication ◽

On Chip

Over the last two decades, microfluidics has received significant attention from both academia and industry, and researchers report thousands of new prototype devices each year for use in a broad range of environmental, pharmaceutical, and biomedical engineering applications. While lab-on-a-chip fabrication costs have continued to decrease, the hardware required for monitoring fluid flows within microfluidic devices themselves remains expensive and often cost prohibitive for researchers interested in starting a microfluidics project. As microfluidic devices become capable of handling complex fluidic systems, low-cost, precise and real time pressure and flow rate measurement capabilities has become increasingly important. While many labs use commercial platforms and sensor, these solutions can often cost thousands of dollars and can be too bulky for on-chip use. Here we present a new inexpensive and easy -to-use piezoresistive pressure and flow sensor that can be easily integrated into existing on-chip microfluidic channels. The sensor consists of PDMS-Carbon black conductive membranes and uses an impedance analyzer to measure impedance change due fluid pressure. The sensor costs several orders of magnitude less than existing commercial platforms and can monitor local fluid pressures and calculate flow rates based on pressure gradient.

Download Full-text

Piezoresistive Conductive Microfluidic Membranes for Low-Cost On-Chip Pressure and Flow Sensing

10.20944/preprints202112.0410.v2 ◽

2022 ◽

Author(s):

Md Nazibul Islam ◽

Steven M Doria ◽

Zachary R Gagnon ◽

Xiaotong Fu

Keyword(s):

Time Pressure ◽

Low Cost ◽

Fluid Pressure ◽

Fluid Flows ◽

Microfluidic Devices ◽

Microfluidic Channels ◽

Impedance Change ◽

Conductive Membranes ◽

Chip Fabrication ◽

On Chip

Over the last two decades, microfluidics has received significant attention from both academia and industry, and researchers report thousands of new prototype devices each year for use in a broad range of environmental, pharmaceutical, and biomedical engineering applications. While lab-on-a-chip fabrication costs have continued to decrease, the hardware required for monitoring fluid flows within microfluidic devices themselves remains expensive and often cost prohibitive for researchers interested in starting a microfluidics project. As microfluidic devices become capable of handling complex fluidic systems, low-cost, precise and real time pressure and flow rate measurement capabilities has become increasingly important. While many labs use commercial platforms and sensor, these solutions can often cost thousands of dollars and can be too bulky for on-chip use. Here we present a new inexpensive and easy -to-use piezoresistive pressure and flow sensor that can be easily integrated into existing on-chip microfluidic channels. The sensor consists of PDMS-Carbon black conductive membranes and uses an impedance analyzer to measure impedance change due fluid pressure. The sensor costs several orders of magnitude less than existing commercial platforms and can monitor local fluid pressures and calculate flow rates based on pressure gradient.

Download Full-text

Platforms for Production of Protein-Based Vaccines: From Classical to Next-Generation Strategies

Biomolecules ◽

10.3390/biom11081072 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1072

Author(s):

Raquel Cid ◽

Jorge Bolívar

Keyword(s):

Infectious Diseases ◽

Mammalian Cells ◽

Vaccine Development ◽

Low Cost ◽

Cost Effective ◽

Insect Larvae ◽

Subunit Vaccines ◽

Effective Strategies ◽

Alternative Systems ◽

Inactivated Vaccines

To date, vaccination has become one of the most effective strategies to control and reduce infectious diseases, preventing millions of deaths worldwide. The earliest vaccines were developed as live-attenuated or inactivated pathogens, and, although they still represent the most extended human vaccine types, they also face some issues, such as the potential to revert to a pathogenic form of live-attenuated formulations or the weaker immune response associated with inactivated vaccines. Advances in genetic engineering have enabled improvements in vaccine design and strategies, such as recombinant subunit vaccines, have emerged, expanding the number of diseases that can be prevented. Moreover, antigen display systems such as VLPs or those designed by nanotechnology have improved the efficacy of subunit vaccines. Platforms for the production of recombinant vaccines have also evolved from the first hosts, Escherichia coli and Saccharomyces cerevisiae, to insect or mammalian cells. Traditional bacterial and yeast systems have been improved by engineering and new systems based on plants or insect larvae have emerged as alternative, low-cost platforms. Vaccine development is still time-consuming and costly, and alternative systems that can offer cost-effective and faster processes are demanding to address infectious diseases that still do not have a treatment and to face possible future pandemics.

Download Full-text

Itaconate Alters Succinate and Coenzyme A Metabolism via Inhibition of Mitochondrial Complex II and Methylmalonyl-CoA Mutase

Metabolites ◽

10.3390/metabo11020117 ◽

2021 ◽

Vol 11 (2) ◽

pp. 117

Author(s):

Thekla Cordes ◽

Christian M. Metallo

Keyword(s):

Amino Acid ◽

Metabolic Pathways ◽

Mammalian Cells ◽

Coenzyme A ◽

Cultured Cells ◽

Tca Cycle ◽

Regulatory Function ◽

Reversible Inhibitor ◽

Complex Ii ◽

Branched Chain

Itaconate is a small molecule metabolite that is endogenously produced by cis-aconitate decarboxylase-1 (ACOD1) in mammalian cells and influences numerous cellular processes. The metabolic consequences of itaconate in cells are diverse and contribute to its regulatory function. Here, we have applied isotope tracing and mass spectrometry approaches to explore how itaconate impacts various metabolic pathways in cultured cells. Itaconate is a competitive and reversible inhibitor of Complex II/succinate dehydrogenase (SDH) that alters tricarboxylic acid (TCA) cycle metabolism leading to succinate accumulation. Upon activation with coenzyme A (CoA), itaconyl-CoA inhibits adenosylcobalamin-mediated methylmalonyl-CoA (MUT) activity and, thus, indirectly impacts branched-chain amino acid (BCAA) metabolism and fatty acid diversity. Itaconate, therefore, alters the balance of CoA species in mitochondria through its impacts on TCA, amino acid, vitamin B12, and CoA metabolism. Our results highlight the diverse metabolic pathways regulated by itaconate and provide a roadmap to link these metabolites to potential downstream biological functions.

Download Full-text

Preparation and Characterization of High-Efficiency Magnetic Heavy Metal Capture Flocculants

Water ◽

10.3390/w13131732 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1732

Author(s):

Yuanyuan Yu ◽

Yongjun Sun ◽

Jun Zhou ◽

Aowen Chen ◽

Kinjal J. Shah

Keyword(s):

Heavy Metal ◽

Reaction Time ◽

High Efficiency ◽

Removal Rate ◽

Low Cost ◽

Monomer Concentration ◽

Synthesis Process ◽

Response Surface Optimization ◽

Metal Capture ◽

Total Monomer Concentration

In this study, a high-efficiency magnetic heavy metal flocculant MF@AA was prepared based on carboxymethyl chitosan and magnetic Fe3O4. It was characterized by SEM, FTIR, XPS, XRD and VSM, and the Cu(II) removal rate was used as the evaluation basis for the preparation process. The effects of AMPS content, total monomer concentration, photoinitiator concentration and reaction time on the performance of MF@AA flocculation to remove Cu(II) were studied. The characterization results show that MF@AA has been successfully prepared and exhibits good magnetic induction characteristics. The synthesis results show that under the conditions of 10% AMPS content, 35% total monomer concentration, 0.04% photoinitiator concentration, and 1.5 h reaction time, the best yield of MF@AA is 77.69%. The best removal rate is 87.65%. In addition, the response surface optimization of the synthesis process of MF@AA was performed. The optimal synthesis ratio was finally determined as iron content 6.5%, CMFS: 29.5%, AM: 53.9%, AMPS: 10.1%. High-efficiency magnetic heavy metal flocculant MF@AA shows excellent flocculation performance in removing Cu(II). This research provides guidance and ideas for the development of efficient and low-cost flocculation technology to remove Cu(II) in wastewater.

Download Full-text

Visualization of Surface Acoustic Waves in Thin Liquid Films

Scientific Reports ◽

10.1038/srep21980 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 20

Author(s):

R. W. Rambach ◽

J. Taiber ◽

C. M. L. Scheck ◽

C. Meyer ◽

J. Reboud ◽

...

Keyword(s):

Liquid Film ◽

Acoustic Waves ◽

Low Cost ◽

Thin Liquid Film ◽

Surface Acoustic Waves ◽

Liquid Films ◽

Theoretical Description ◽

Propagation Path ◽

Microfluidic Channels ◽

Potential Applications

Abstract We demonstrate that the propagation path of a surface acoustic wave (SAW), excited with an interdigitated transducer (IDT), can be visualized using a thin liquid film dispensed onto a lithium niobate (LiNbO3) substrate. The practical advantages of this visualization method are its rapid and simple implementation, with many potential applications including in characterising acoustic pumping within microfluidic channels. It also enables low-cost characterisation of IDT designs thereby allowing the determination of anisotropy and orientation of the piezoelectric substrate without the requirement for sophisticated and expensive equipment. Here, we show that the optical visibility of the sound path critically depends on the physical properties of the liquid film and identify heptane and methanol as most contrast rich solvents for visualization of SAW. We also provide a detailed theoretical description of this effect.

Download Full-text

Adsorption of copper ions on Magnolia officinalis residues after solid-phase fermentation with Phanerochaete chrysosporium

Open Chemistry ◽

10.1515/chem-2019-0111 ◽

2019 ◽

Vol 17 (1) ◽

pp. 1173-1184 ◽

Cited By ~ 2

Author(s):

Fengyun Tao ◽

Yangping Liu ◽

Junliang Chen ◽

Peng Wang ◽

Qing Huo

Keyword(s):

Chinese Medicine ◽

Phanerochaete Chrysosporium ◽

Solid Phase ◽

Copper Ions ◽

Removal Rate ◽

Low Cost ◽

Preparation Technique ◽

Adsorption Enthalpy ◽

Pseudo Second Order ◽

Magnolia Officinalis

AbstractThe disposal of residues while manufacturing Chinese medicine has always been an issue that concerns pharmaceutical factories. Phanerochaete chrysosporium was inoculated into the residues of Magnolia officinalis for solid-phase fermentation to enzymatically hydrolyze the lignin in the residues and thus to improve the efficiency of removal of the copper ions from residues for the utilization of residues from Chinese medicine. With the increase in activities of lignin-degrading enzymes, especially during the fermentation days 6 to 9, the removal rate of copper ions using M. officinalis residues increased dramatically. The rate of removal reached the maximum on the 14th day and was 3.15 times higher than the initial value. The rate of adsorption of copper ions on the fermentation-modified M. officinalis residues followed the pseudo-second-order kinetics. The adsorption isotherms were consistent with the Freundlich models. The adsorption enthalpy was positive, indicating that it was endothermic and elevation in temperature was favorable to this adsorption process. The adsorption free energy was negative, implying the spontaneity of the process. The copper ions adsorbed could be effectively recovered using 0.2 M hydrochloric acid solution. After five successive cycles of adsorption-regeneration, the fermentation-modified M. officinalis residues exhibited a stable adsorption capacity and greater reusability. The M. officinalis residues fermented with P. chrysosporium are low-cost and environmentally friendly copper ions adsorbent, and this preparation technique realizes the optimum utilization of Chinese medicine residues.

Download Full-text

Integrated Process for Textile Cotton Waste (TCW) Valorization: Waste-to-Energy and Wastewater Decontamination

Volume 6B: Energy ◽

10.1115/imece2016-66706 ◽

2016 ◽

Author(s):

A. Ribeiro ◽

C. Vilarinho ◽

J. Araújo ◽

J. Carvalho

Keyword(s):

Raw Materials ◽

Removal Rate ◽

Low Cost ◽

Calorific Value ◽

Waste To Energy ◽

Synthetic Wastewater ◽

Small Scale ◽

World Population ◽

Cotton Waste ◽

Textile Industries

The increasing of world population, industrialization and global consuming, existing market products existed in the along with diversification of raw materials, are responsible for an exponential increase of wastes. This scenario represents loss of resources and ultimately causes air, soils and water pollution. Therefore, proper waste management is currently one of the major challenges faced by modern societies. Textile industries represents, in Portugal, almost 10% of total productive transforming sector and 19% of total employments in the sector composed by almost 7.000 companies. One of the main environmental problems of textile industries is the production of significant quantities of wastes from its different processing steps. According to the Portuguese Institute of Statistics (INE) these industries produce almost 500.000 tons of wastes each year, with the textile cotton waste (TCW) being the most expressive. It was estimated that 4.000 tons of TCW are produced each year in Portugal. In this work an integrated TCW valorisation procedure was evaluated, firstly by its thermal and energetic valorisation with slow pyrolysis followed by the utilization of biochar by-product, in lead and chromium synthetic wastewater decontamination. Pyrolysis experiments were conducted in a small scale rotating pyrolysis reactor with 0.1 m3 of total capacity. Results of pyrolysis experiments showed the formation of 0,241 m3 of biogas for each kilogram of TCW. Results also demonstrated that the biogas is mostly composed by hydrogen (22%), methane (14 %), carbon monoxide (20%) and carbon dioxide (12%), which represents a total high calorific value of 12.3 MJ/Nm3. Regarding biochar, results of elemental analysis demonstrated a high percentage of carbon driving its use as low cost adsorbent. Adsorption experiments were conducted with lead and chromium synthetic wastewaters (25, 50 and 100 mg L−1) in batch vessels with controlled pH. It was evaluated the behaviour of adsorption capacity and removal rate of each metal during 120 minutes of contact time using 5, 10 and 50 g L−1 of adsorbent dosage. Results indicated high affinity of adsorbent with each tested metal with 78% of removal rate in chromium and 95% in lead experiments. This suggests that biochar from TCW pyrolysis may be appropriated to wastewaters treatment, with high contents of heavy metals and it can be an effective alternative to activated carbon.

Download Full-text

Acoustic trapping in bubble-bounded micro-cavities

Optofluidics Microfluidics and Nanofluidics ◽

10.1515/optof-2016-0003 ◽

2016 ◽

Vol 3 (1) ◽

Author(s):

P. O’Mahoney ◽

C. McDougall ◽

P. Glynne-Jones ◽

M. P. MacDonald

Keyword(s):

Lower Order ◽

Cavity Mode ◽

Microfluidic Channels ◽

Air Bubbles ◽

Longitudinal Acoustic ◽

Lateral Mode ◽

Micro Cavity ◽

Trapping Sites

AbstractWe present a method for controllably producing longitudinal acoustic trapping sites inside microfluidic channels. Air bubbles are injected into a micro-capillary to create bubble-bounded ‘micro-cavities’. A cavity mode is formed that shows controlled longitudinal acoustic trapping between the two air/water interfaces along with the levitation to the centre of the channel that one would expect from a lower order lateral mode. 7 μm and 10 μm microspheres are trapped at the discrete acoustic trapping sites in these micro-cavities.We show this for several lengths of micro-cavity.

Download Full-text