A low-cost thin layer coulometric microfluidic device based on an ion-selective membrane for calcium determination

The Analyst ◽  
2014 ◽  
Vol 139 (1) ◽  
pp. 48-51 ◽  
Author(s):  
Denis Dorokhin ◽  
Gastón A. Crespo ◽  
Majid Ghahraman Afshar ◽  
Eric Bakker
Keyword(s):  
Thin Layer ◽  
Microfluidic Device ◽  
Low Cost ◽  
Selective Membrane ◽  
Calcium Determination

Comparison of UV- and Derivative-Spectrophotometric and HPTLC UVDensitometric Methods for the Determination of Amrinone and Milrinone in Bulk Drugs

2020 ◽  
Vol 16 (3) ◽  
pp. 246-253
Author(s):  
Marcin Gackowski ◽  
Marcin Koba ◽  
Stefan Kruszewski
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
High Performance ◽  
Low Cost ◽  
Uv Spectra ◽  
Derivative Spectrophotometry ◽  
Therapeutic Monitoring ◽  
Bulk Drug ◽  
Layer Chromatography ◽  
Standard Solutions

Background: Spectrophotometry and thin layer chromatography have been commonly applied in pharmaceutical analysis for many years due to low cost, simplicity and short time of execution. Moreover, the latest modifications including automation of those methods have made them very effective and easy to perform, therefore, the new UV- and derivative spectrophotometry as well as high performance thin layer chromatography UV-densitometric (HPTLC) methods for the routine estimation of amrinone and milrinone in pharmaceutical formulation have been developed and compared in this work since European Pharmacopoeia 9.0 has yet incorporated in an analytical monograph a method for quantification of those compounds. Methods: For the first method the best conditions for quantification were achieved by measuring the lengths between two extrema (peak-to-peak amplitudes) 252 and 277 nm in UV spectra of standard solutions of amrinone and a signal at 288 nm of the first derivative spectra of standard solutions of milrinone. The linearity between D252-277 signal and concentration of amironone and 1D288 signal of milrinone in the same range of 5.0-25.0 μg ml/ml in DMSO:methanol (1:3 v/v) solutions presents the square correlation coefficient (r2) of 0,9997 and 0.9991, respectively. The second method was founded on HPTLC on silica plates, 1,4-dioxane:hexane (100:1.5) as a mobile phase and densitometric scanning at 252 nm for amrinone and at 271 nm for milrinone. Results: The assays were linear over the concentration range of 0,25-5.0 μg per spot (r2=0,9959) and 0,25-10.0 μg per spot (r2=0,9970) for amrinone and milrinone, respectively. The mean recoveries percentage were 99.81 and 100,34 for amrinone as well as 99,58 and 99.46 for milrinone, obtained with spectrophotometry and HPTLC, respectively. Conclusion: The comparison between two elaborated methods leads to the conclusion that UV and derivative spectrophotometry is more precise and gives better recovery, and that is why it should be applied for routine estimation of amrinone and milrinone in bulk drug, pharmaceutical forms and for therapeutic monitoring of the drug.

scholarly journals Design and Manufacturing of a Disposable, Cyclo-Olefin Copolymer, Microfluidic Device for a Biosensor †

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1178 ◽  
Author(s):  
Jorge Prada ◽  
Christina Cordes ◽  
Carsten Harms ◽  
Walter Lang
Keyword(s):  
Microfluidic Device ◽  
Heating Temperature ◽  
Low Cost ◽  
Reaction Chamber ◽  
Microfluidic System ◽  
Heating Process ◽  
Design And Manufacturing ◽  
On Chip ◽  
Working Parameters ◽  
Auto Fluorescence

This contribution outlines the design and manufacturing of a microfluidic device implemented as a biosensor for retrieval and detection of bacteria RNA. The device is fully made of Cyclo-Olefin Copolymer (COC), which features low auto-fluorescence, biocompatibility and manufacturability by hot-embossing. The RNA retrieval was carried on after bacteria heat-lysis by an on-chip micro-heater, whose function was characterized at different working parameters. Carbon resistive temperature sensors were tested, characterized and printed on the biochip sealing film to monitor the heating process. Off-chip and on-chip processed RNA were hybridized with capture probes on the reaction chamber surface and identification was achieved by detection of fluorescence tags. The application of the mentioned techniques and materials proved to allow the development of low-cost, disposable albeit multi-functional microfluidic system, performing heating, temperature sensing and chemical reaction processes in the same device. By proving its effectiveness, this device contributes a reference to show the integration potential of fully thermoplastic devices in biosensor systems.

scholarly journals Negative Pressure Provides Simple and Stable Droplet Generation in a Flow-Focusing Microfluidic Device

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 662
Author(s):  
Nikita A. Filatov ◽  
Anatoly A. Evstrapov ◽  
Anton S. Bukatin
Keyword(s):  
Microfluidic Device ◽  
Negative Pressure ◽  
Low Cost ◽  
Control Valve ◽  
Droplet Microfluidics ◽  
Droplet Generation ◽  
Electric Signal ◽  
Absolute Pressure ◽  
Flow Focusing ◽  
Wide Range

Droplet microfluidics is an extremely useful and powerful tool for industrial, environmental, and biotechnological applications, due to advantages such as the small volume of reagents required, ultrahigh-throughput, precise control, and independent manipulations of each droplet. For the generation of monodisperse water-in-oil droplets, usually T-junction and flow-focusing microfluidic devices connected to syringe pumps or pressure controllers are used. Here, we investigated droplet-generation regimes in a flow-focusing microfluidic device induced by the negative pressure in the outlet reservoir, generated by a low-cost mini diaphragm vacuum pump. During the study, we compared two ways of adjusting the negative pressure using a compact electro-pneumatic regulator and a manual airflow control valve. The results showed that both types of regulators are suitable for the stable generation of monodisperse droplets for at least 4 h, with variations in diameter less than 1 µm. Droplet diameters at high levels of negative pressure were mainly determined by the hydrodynamic resistances of the inlet microchannels, although the absolute pressure value defined the generation frequency; however, the electro-pneumatic regulator is preferable and convenient for the accurate control of the pressure by an external electric signal, providing more stable pressure, and a wide range of droplet diameters and generation frequencies. The method of droplet generation suggested here is a simple, stable, reliable, and portable way of high-throughput production of relatively large volumes of monodisperse emulsions for biomedical applications.

scholarly journals Micropipette-Based Microfluidic Device for Monodisperse Microbubbles Generation

Micromachines ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 387
Author(s):  
Carlos Toshiyuki Matsumi ◽  
Wilson José da Silva ◽  
Fábio Kurt Schneider ◽  
Joaquim Miguel Maia ◽  
Rigoberto E. M. Morales ◽  
...  
Keyword(s):  
Electric Fields ◽  
Microfluidic Device ◽  
Soft Lithography ◽  
Low Cost ◽  
Characteristic Curve ◽  
Microfluidic Devices ◽  
Average Diameter ◽  
Internal Diameter ◽  
Medical Diagnostic ◽  
Average Size

Microbubbles have various applications including their use as carrier agents for localized delivery of genes and drugs and in medical diagnostic imagery. Various techniques are used for the production of monodisperse microbubbles including the Gyratory, the coaxial electro-hydrodynamic atomization (CEHDA), the sonication methods, and the use of microfluidic devices. Some of these techniques require safety procedures during the application of intense electric fields (e.g., CEHDA) or soft lithography equipment for the production of microfluidic devices. This study presents a hybrid manufacturing process using micropipettes and 3D printing for the construction of a T-Junction microfluidic device resulting in simple and low cost generation of monodisperse microbubbles. In this work, microbubbles with an average size of 16.6 to 57.7 μm and a polydispersity index (PDI) between 0.47% and 1.06% were generated. When the device is used at higher bubble production rate, the average diameter was 42.8 μm with increased PDI of 3.13%. In addition, a second-order polynomial characteristic curve useful to estimate micropipette internal diameter necessary to generate a desired microbubble size is presented and a linear relationship between the ratio of gaseous and liquid phases flows and the ratio of microbubble and micropipette diameters (i.e., Qg/Ql and Db/Dp) was found.

scholarly journals Low Cost Micro Milling Machine for Prototyping Plastic Microfluidic Devices

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 707 ◽  
Author(s):  
Md Mubarak Hossain ◽  
Tanzilur Rahman
Keyword(s):  
Developing Countries ◽  
Microfluidic Device ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Micro Milling ◽  
Biological Research ◽  
Milling Machine ◽  
Plastic Materials ◽  
Milling Machines

Micro-milling is one of the commonly used methods of fabrication of microfluidic devices necessary for cell biological research and application. Commercial micro-milling machines are expensive, and researchers in developing countries can’t afford them. Here, we report the design and the development of a low-cost (<130 USD) micro milling machine and asses the prototyping capabilities of microfeatures in plastic materials. We demonstrate that the developed machine can be used in fabricating the plastic based microfluidic device.

An Integrated PDMS Microfluidic Device for Dielectrophoretic Separation of Malignant Cells

2005 ◽  
Author(s):  
Thirukumaran T. Kanagasabapathi ◽  
Colin Dalton ◽  
Karan V. I. S. Kaler
Keyword(s):  
Microfluidic Device ◽  
Low Cost ◽  
Polystyrene Latex ◽  
Yeast Cells ◽  
Microfluidic Channels ◽  
Non Invasive ◽  
Latex Beads ◽  
Planar Electrodes ◽  
And Performance ◽  
Cancerous Cells

Dielectrophoresis (DEP) has been successfully applied and demonstrated to provide novel and non-invasive means for characterizing, manipulating, trapping, separating and isolating microscopic sized particles, including biological cells. In this article, we report on the design, fabrication and performance of a novel, low cost, integrated Poly(dimethylsiloxane) (PDMS)/DEP microfluidic device capable of controlled manipulation of microscopic sized cells and particles that can be simultaneously utilized both for DEP spectral analysis and cell sorting. We have prototyped microfluidic channels, with DEP microelectrodes incorporated within PDMS channels. Previously, we have evaluated the operation and performance of a prototype device using various dielectric and biological particles, including yeast cells and polystyrene latex beads. In this paper, we report initial experimental observations on malignant cancerous cells. Non-viable cells, due to positive DEP, were attracted to the planar electrodes at frequencies between 200–600 kHz and were clearly repelled from the electrodes, due to negative DEP, at frequencies above 10 MHz.

scholarly journals IR-Live: fabrication of a low-cost plastic microfluidic device for infrared spectromicroscopy of living cells

Lab on a Chip ◽  
2016 ◽  
Vol 16 (9) ◽  
pp. 1644-1651 ◽  
Author(s):  
G. Birarda ◽  
A. Ravasio ◽  
M. Suryana ◽  
S. Maniam ◽  
H.-Y. N. Holman ◽  
...  
Keyword(s):  
Microfluidic Device ◽  
Biological Samples ◽  
Low Cost ◽  
Living Cells ◽  
Production Costs ◽  
Minimal Access ◽  
Micro Fabrication ◽  
New Approach ◽  
Lower Production

We report an innovative and simple way to fabricate plastic devices with infrared transparent view-ports enabling infrared spectromicroscopy of living biological samples. The main advantages of this new approach include lower production costs and a minimal access to a micro-fabrication facility.

Determination of Escherichia coli in urine using a low-cost foil-based microfluidic device

Talanta ◽  
2017 ◽  
Vol 170 ◽  
pp. 36-40
Author(s):  
Tereza Mašková ◽  
Lenka Hárendarčíková ◽  
Jan Petr
Keyword(s):  
Escherichia Coli ◽  
Microfluidic Device ◽  
Low Cost
Sign in / Sign up

Export Citation Format

Share Document