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Article
Publication date: 25 January 2008

Arvind Chandrasekaran and Muthukumaran Packirisamy

This paper proposes to examine a simple and cost‐effective method of integrating a reflector surface with a silicon‐based microfluidic channel for enhanced biosensing through the…

Abstract

Purpose

This paper proposes to examine a simple and cost‐effective method of integrating a reflector surface with a silicon‐based microfluidic channel for enhanced biosensing through the method of fluorescence in a microfluidics and nanofluidics‐based lab‐on‐a‐chip device.

Design/methodology/approach

Herein, the reflector is integrated with silicon‐based microfluidic channels and fluorescence measurements were carried out using alexafluor 647 particles. Two types of microfluidic channel surfaces were used, with and without reflector integration, for the experiments.

Findings

The experimental results prove that the proposed technique of partial reflector integration within microfluidic or nanofluidic channel surfaces is highly suitable for fluorescence‐based detection of single molecules and low concentration fluorophore‐tagged receptors.

Originality/value

It is believed that this is a novel work of integrating a reflector with a microfluidic channel surface for fluorescence‐based biodetection. This method will be very useful for fluorescence‐based biosensors in detecting low concentration fluorophores and single molecules.

Details

Sensor Review, vol. 28 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 11 September 2009

Dennis Patrick Webb, Benedikt Knauf, Chanqing Liu, David Hutt and Paul Conway

Microfluidic or “lab‐on‐a‐chip” technology is seen as a key enabler in the rapidly expanding market for medical point‐of‐care and other kinds of portable diagnostic device. The…

Abstract

Purpose

Microfluidic or “lab‐on‐a‐chip” technology is seen as a key enabler in the rapidly expanding market for medical point‐of‐care and other kinds of portable diagnostic device. The purpose of this paper is to discuss two proposed packaging processes for large‐scale manufacture of microfluidic systems.

Design/methodology/approach

In the first packaging process, polymer overmoulding of a microfluidic chip is used to form a fluidic manifold integrated with the device in a single step. The anticipated advantages of the proposed method of packaging are ease of assembly and low part count. The second process involves the use of low‐frequency induction heating (LFIH) for the sealing of polymer microfluidics. The method requires no chamber, and provides fast and selective heating to the interface to be joined.

Findings

Initial work with glass microfluidics demonstrates feasibility for overmoulding through two separate sealing principles. One uses the overmould as a physical support structure and providing sealing using a compliant ferrule. The other relies on adhesion between the material of the overmould and the microfluidic device to provide a seal. As regards LFIH work on selection and structuring of susceptor materials is reported, together with analysis of the dimensions of the heat‐affected zone. Acrylic plates are joined using a thin (<10 μm) nickel susceptor providing a fluid seal that withstands a pressure of 590 kPa.

Originality/value

Microfluidic chips have until now been produced in relatively small numbers. To scale‐up from laboratory systems to the production volumes required for mass markets, packaging methods need to be adapted to mass manufacture.

Details

Sensor Review, vol. 29 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 2 July 2018

Karol Malecha, Jan Macioszczyk, Piotr Slobodzian and Jacek Sobkow

This paper aims to focus on the application of low temperature co-fired ceramic (LTCC) technology in the fabrication of a microfluidic module with integrated microwave components…

Abstract

Purpose

This paper aims to focus on the application of low temperature co-fired ceramic (LTCC) technology in the fabrication of a microfluidic module with integrated microwave components. The design, technology and performance of such an LTCC-based module is investigated. The rapid heating of liquid samples on a microliter scale is shown to be possible with the use of microwaves.

Design/methodology/approach

The developed microwave-microfluidic module was fabricated using well-known LTCC technology. The finite element method was used to design the geometry of the microwave circuit. Various numerical simulations for different liquids were performed. Finally, the performance of the real LTCC-based microwave-microfluidic module was examined experimentally.

Findings

LTCC materials and technology can be used in the fabrication of microfluidic modules which use microwaves in the heating of the liquid sample. LTCC technology permits the fabrication of matching circuits with appropriate geometry, whereas microwave power can be used to heat up the liquid samples on a microliter scale.

Research limitations/implications

The main limitation of the presented work is found to be in conjunction with LTCC technology. The dimensions and shape of the deposited conductors (e.g. microstrip line, matching circuit) depend on the screen-printing process. A line with resolution lower than 75 µm with well-defined edges is difficult to obtain. This can have an effect on the high-frequency properties of the LTCC modules.

Practical implications

The presented LTCC-based microfluidic module with integrated microwave circuits provides an opportunity for the further development of various micro-total analysis systems or lab-on-chips in which the rapid heating of liquid samples in low volumes is needed (e.g. miniature real-time polymerase chain reaction thermocycler).

Originality/value

Examples of the application of LTCC technology in the fabrication of microwave circuits and microfluidic systems can be found in the available literature. However, the LTCC-based module which combines microwave and microfluidic components has yet to have been reported. The preliminary work on the design, fabrication and properties of the LTCC microfluidic module with integrated microwave components is presented in this paper.

Details

Microelectronics International, vol. 35 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 3 August 2015

Karol Malecha, Elżbieta Remiszewska and Dorota G Pijanowska

The purpose of this paper is to focus on the technology and performance of the miniature microfluidic module for urea determination. The presented module was made using…

Abstract

Purpose

The purpose of this paper is to focus on the technology and performance of the miniature microfluidic module for urea determination. The presented module was made using low-temperature co-fired ceramics (LTCC). It shows the possibility for the integration of the bioreceptor layers with structures that have been fabricated using modern microelectronic technology.

Design/methodology/approach

The presented microfluidic module was fabricated using LTCC technology. The possibility for the fabrication of an enzymatic microreactor in a multilayer ceramic substrate, made of CeramTec glass ceramic (GC) material systems with an integrated thick-film heater, is studied. Different configurations of the LTCC/heater materials (gold, silvers and palladium-silver) are taken into account. The performance of the LTCC-based microfluidic module with the integrated heater and immobilized enzyme was examined experimentally.

Findings

A compatible material for the heater embedded in the CeramTec GC-based structures was found. The preliminary measurements made for the test solution containing various concentrations of urea have shown stability (for seven days of operation) and a relatively high signal-to-noise ratio (above 3 pH units) for the microreactor’s output signal.

Research limitations/implications

The presented research is a preliminary work which is focused on the fabrication of the LTCC-based microfluidic module, with an integrated heater and immobilized enzyme for urea determination. The device was positively tested using a model reaction of the hydrolysis of urea. However, urea concentration in real (biological) fluid should also be measured.

Practical implications

The development of the LTCC-based microfluidic module for urea determination provides opportunity for the construction of a lab-on-chip, or μTAS-type system, for fast medical diagnoses and the continuous monitoring of various biochemical parameters, e.g. for estimating the effectiveness of hemodialysis.

Originality/value

This paper shows the design, fabrication and performance of the novel microfluidic module for urea determination, made with LTCC technology.

Details

Microelectronics International, vol. 32 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 August 2016

Karol Malecha

This paper aims to present a research on utilization of an irreversible bonding between non-transparent low temperature co-fired ceramics (LTCC) and transparent…

Abstract

Purpose

This paper aims to present a research on utilization of an irreversible bonding between non-transparent low temperature co-fired ceramics (LTCC) and transparent poly(dimethylsiloxane) (PDMS). The research presented in this paper is focused on the technology and performance of the miniature microfluidic module for fluorescence measurement.

Design/methodology/approach

The chemical combination of both materials is achieved through surface modification using argon-oxygen dielectric barrier discharge (DBD) plasma. According to the performed spectroscopic analyses (X-ray photoelectron spectroscopy, XPS; attenuated total reflection-Fourier infrared spectroscopy, ATR-FTIR) and contact angle measurements, the LTCC and PDMS surfaces are oxidized during the process. The presented microfluidic module was fabricated using LTCC technology. The possibility for the fabrication of LTCC-PDMS microfluidic fluorescent sensor is studied. The performance of the sensor was examined experimentally.

Findings

As a result of DBD plasma oxidation, the LTCC and PDMS surfaces change in character from hydrophobic to hydrophilic and were permanently bonded. The presented LTCC-PDMS bonding technique was used to fabricate a microfluidic fluorescent sensor. The preliminary measurements of the sensor have proven that it is possible to observe the fluorescence of a liquid sample from a very small volume.

Research limitations/implications

The presented research is a preliminary work which is focused on the fabrication of the LTCC-PDMS fluorescent sensor. The microfluidic device was positively tested only for ethanolic fluorescein solutions. Therefore, fluorescence measurements should be performed for biological specimen (e.g. DNA).

Practical implications

The LTCC-PDMS bonding technology combines the advantages of both materials. One the one hand, transparent PDMS with precise, transparent three-dimensional structures can be fabricated using hot embossing, soft lithography or laser ablation. On the other hand, rigid LTCC substrate consisting of microfluidic structures, electric interconnections, heaters and optoelectronic components can be fabricated. The development of the LTCC-PDMS microfluidic modules provides opportunity for the construction of a lab-on-chip, or micro-total analysis systems-type system, for analytical chemistry and fast medical diagnoses.

Originality/value

This paper shows utilization of the PDMS-LTCC bonding technology for microfluidics. Moreover, the design, fabrication and performance of the PDMS-LTCC fluorescent sensor are presented.

Details

Microelectronics International, vol. 33 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 2 July 2018

Darko Belavic, Andraž Bradeško and Hana Uršič

The purpose of this study is to design, fabricate and investigate low-temperature co-fired ceramic (LTCC) structures with integrated microfluidic elements. Special attention is…

Abstract

Purpose

The purpose of this study is to design, fabricate and investigate low-temperature co-fired ceramic (LTCC) structures with integrated microfluidic elements. Special attention is paid to the study of fluid properties of micro-channels and microvalves, which are important constitutive parts of both, microfluidic systems and individual microfluidic devices.

Design/methodology/approach

Several test patterns of fluid channels with different geometry and different types of valves were designed and realized in LTCC technology. All test structures were tested under the flow of two fluids (liquids): water and isopropyl alcohol. Flow rates at different applied pressure were measured and hydrodynamic resistance and diode effect were calculated.

Findings

The investigation of the channels showed that viscosity of fluidic media has significant influence on the hydrodynamic resistance in channels with rectangular cross-section, while this effect is small on channels with square cross-section. The viscosity also has a decisive influence on the diode effect of different shape of valves, and therefore, it is important in the selection of the valve in practical applications.

Research limitations/implications

In this work, the investigation of hydrodynamic resistance of channels and diode effect of passive valves is limited on selected geometry and only on two fluidic media and two applied pressures. All these and some other parameters have a significant influence on fluidic properties, but this will be the topic of the next research work, which will be supported by numerical modelling.

Practical implications

The presented results are useful in the future designing process of LTCC-based microfluidic devices and systems.

Originality/value

Microfluidic in the LTCC structures is an unconventional use of this technology. Therefore, the fluid properties are relatively unsearched. On the other hand, the global use of microfluidic devices and systems is growing rapidly in various applications. They are mostly made by polymer materials, however, in more demanding applications; ceramic is a useful alternative.

Details

Microelectronics International, vol. 35 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 16 March 2015

Amin TermehYousefi, Samira Bagheri and Nahrizul Adib

Biotechnology is closely associated to microfluidics. During the last decade, designs of microfluidic devices such as geometries and scales have been modified and improved…

1304

Abstract

Purpose

Biotechnology is closely associated to microfluidics. During the last decade, designs of microfluidic devices such as geometries and scales have been modified and improved according to the applications for better performance. Numerous sensor technologies existing in the industry has potential use for clinical applications. Fabrication techniques of microfluidics initially rooted from the electromechanical systems (EMS) technology.

Design/methodology/approach

In this review, we emphasized on the most available manufacture approaches to fabricate microchannels, their applications and the properties which make them unique components in biological studies.

Findings

Major fundamental and technological advances demonstrate the enhancing of capabilities and improving the reliability of biosensors based on microfluidic. Several researchers have been reported verity of methods to fabricate different devices based on EMS technology due to the electroconductivity properties and their small size of them. Therefore, controlled fabrication method of MEMS plays an important role to design and fabricate a highly selective detection of medical devices in a variety of biological fluids. Stable, tight and reliable monitoring devices for biological components still remains a massive challenge and several studies focused on MEMS to fabricate simple and easy monitoring devices.

Originality/value

This paper is not submitted or under review in any other journal.

Details

Sensor Review, vol. 35 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 15 August 2019

Arivarasi A. and Anand Kumar

The purpose of this paper is to describe, review, classify and analyze the current challenges in three-dimensional printing processes for combined electrochemical and microfluidic

Abstract

Purpose

The purpose of this paper is to describe, review, classify and analyze the current challenges in three-dimensional printing processes for combined electrochemical and microfluidic fabrication areas, which include printing devices and sensors in specified areas.

Design/methodology/approach

A systematic review of the literature focusing on existing challenges is carried out. Focused toward sensors and devices in electrochemical and microfluidic areas, the challenges are oriented for a discussion exploring the suitability of printing varied geometries in an accurate manner. Classifications on challenges are based on four key categories such as process, material, size and application as the printer designs are mostly based on these parameters.

Findings

A key three-dimensional printing process methodologies have their unique advantages compared to conventional printing methods, still having the challenges to be addressed, in terms of parameters such as cost, performance, speed, quality, accuracy and resolution. Three-dimensional printing is yet to be applied for consumer usable products, which will boost the manufacturing sector. To be specific, the resolution of printing in desktop printers needs improvement. Printing scientific products are halted with prototyping stages. Challenges in three-dimensional printing sensors and devices have to be addressed by forming integrated processes.

Research limitations/implications

The research is underway to define an integrated process-based on three-dimensional Printing. The detailed technical details are not shared for scientific output. The literature is focused to define the challenges.

Practical implications

The research can provide ideas to business on innovative designs. Research studies have scope for improvement ideas.

Social implications

Review is focused on to have an integrated three-dimensional printer combining processes. This is a cost-oriented approach saving much of space reducing complexity.

Originality/value

To date, no other publication reviews the varied three-dimensional printing challenges by classifying according to process, material, size and application aspects. Study on resolution based data is performed and analyzed for improvements. Addressing the challenges will be the solution to identify an integrated process methodology with a cost-effective approach for printing macro/micro/nano objects and devices.

Details

Rapid Prototyping Journal, vol. 25 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 12 January 2023

Supriya Yadav, Kulwant Singh, Anmol Gupta, Mahesh Kumar, Niti Nipun Sharma and Jamil Akhtar

The purpose of this paper is to predict a suitable paper substrate which has high capillary pressure with the tendency of subsequent fluid wrenching in onward direction for the…

Abstract

Purpose

The purpose of this paper is to predict a suitable paper substrate which has high capillary pressure with the tendency of subsequent fluid wrenching in onward direction for the fabrication of microfluidics device application.

Design/methodology/approach

The experiment has been done on the WhatmanTM grade 1, WhatmanTM chromatography and nitrocellulose paper samples which are made by GE Healthcare Life Sciences. The structural characterization of paper samples for surface properties has been done by scanning electron microscope and ImageJ software. Identification of functional groups on the surface of samples has been done by Fourier transform infrared analysis. A finite elemental analysis has also been performed by using the “Multiphase Flow in Porous Media” module of the COMSOL Multiphysics tool which combines Darcy’s law and Phase Transport in Porous Media interface.

Findings

Experimentally, it has been concluded that the paper substrate for flexible microfluidic device application must have large number of internal (intra- and interfiber) pores with fewer void spaces (external pores) that have high capillary pressure to propel the fluid in onward direction with narrow paper fiber channel.

Originality/value

Surface structure has a dynamic impact in paper substrate utilization in multiple applications such as paper manufacturing, printing process and microfluidics applications.

Details

Microelectronics International, vol. 41 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Open Access
Article
Publication date: 29 June 2021

C. Ahamed Saleel, Saad Ayed Alshahrani, Asif Afzal, Maughal Ahmed Ali Baig, Sarfaraz Kamangar and T.M. Yunus Khan

Joule heating effect is a pervasive phenomenon in electro-osmotic flow because of the applied electric field and fluid electrical resistivity across the microchannels. Its effect…

594

Abstract

Purpose

Joule heating effect is a pervasive phenomenon in electro-osmotic flow because of the applied electric field and fluid electrical resistivity across the microchannels. Its effect in electro-osmotic flow field is an important mechanism to control the flow inside the microchannels and it includes numerous applications.

Design/methodology/approach

This research article details the numerical investigation on alterations in the profile of stream wise velocity of simple Couette-electroosmotic flow and pressure driven electro-osmotic Couette flow by the dynamic viscosity variations happened due to the Joule heating effect throughout the dielectric fluid usually observed in various microfluidic devices.

Findings

The advantages of the Joule heating effect are not only to control the velocity in microchannels but also to act as an active method to enhance the mixing efficiency. The results of numerical investigations reveal that the thermal field due to Joule heating effect causes considerable variation of dynamic viscosity across the microchannel to initiate a shear flow when EDL (Electrical Double Layer) thickness is increased and is being varied across the channel.

Originality/value

This research work suggest how joule heating can be used as en effective mechanism for flow control in microfluidic devices.

Details

Frontiers in Engineering and Built Environment, vol. 1 no. 2
Type: Research Article
ISSN: 2634-2499

Keywords

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