One-Step Polylactic Acid Screen-Printing Microfluidic Paper-Based Analytical Device: Application for Simultaneous Detection of Nitrite and Nitrate in Food Samples

In this work, we report a one-step approach for fabricating screened-printed microfluidic paper-based analytical devices (μPADs) using polylactic acid as a new hydrophobic material. A polylactic acid solution was screen printed onto chromatography papers to create hydrophobic patterns for fluidic channels. The optimal polylactic acid concentration for successful device fabrication is 9% w/v. The μPADs were fabricated within 2 min and provided high reproducibility and stability. The utility of polylactic acid screen-printing was demonstrated for the simultaneous detection of nitrite and nitrate using colorimetric detection. Under optimized experimental conditions, the detection limits and the linear ranges, respectively, were 1.2 mg L−1 and 2–10 mg L−1 for nitrite and 3.6 mg L−1 and 10–50 mg L−1 for nitrate. The detection times for both ions were found to be within 12 min. The developed μPAD was applied for the simultaneous determination of these ions in food samples, and no significant differences in the analytical results were observed compared to those of the reference method. The polylactic acid screen-printing approach presented here provides a simple, rapid, and cost-effective alternative fabrication method for fabricating μPADs.

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Simultaneous Detection of Four Foodborne Viruses in Food Samples Using a One-Step Multiplex Reverse Transcription PCR

Journal of Microbiology and Biotechnology ◽

10.4014/jmb.1710.10008 ◽

2018 ◽

Vol 28 (2) ◽

pp. 210-217 ◽

Cited By ~ 2

Author(s):

Shin-Young Lee ◽

Mi-Ju Kim ◽

Hyun-Joong Kim ◽

KwangCheol Casey Jeong ◽

Hae-Yeong Kim

Keyword(s):

Reverse Transcription ◽

Simultaneous Detection ◽

Food Samples ◽

Foodborne Viruses ◽

Reverse Transcription Pcr ◽

One Step

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Direct Spectrophotometric Determination of Cefuroxime Axetil in Pure Form and Pharmaceutical Dosage Forms.

JOURNAL OF ADVANCES IN CHEMISTRY ◽

10.24297/jac.v15i2.7878 ◽

2018 ◽

Vol 15 (2) ◽

pp. 6282-6295

Author(s):

Abdul Aziz Ramadan ◽

Marwa Bakdash

Keyword(s):

Reference Method ◽

Cost Effective ◽

Bromothymol Blue ◽

Cefuroxime Axetil ◽

Dosage Forms ◽

Experimental Conditions ◽

Pharmaceutical Dosage Forms ◽

Tablet Dosage ◽

Good Agreement

A simple, direct and cost-effective spectrophotometric method for determination of cefuroxime axetil (CRXA) in pure and tablet dosage forms was applied. This method is based on formation of ion-pair complex ([CRXA]:[BTB]) between CRXA and bromothymol blue (BTB) in chloroform. Beer’s law in the optimum experimental conditions using [CRXA]:[BTB] complex is valid within a concentration range of 2.00-50.00 ?M (1.021–25.524 ?g.mL-1). The developed method is applied for the determination of CRXA in pure and its commercial tablets without any interference from excipients with average assay of 96.8 to 101.6% and the results are in good agreement with those obtained by the HPLC reference method. Associated drugs (sulbactam and linesolid) with cefuroxime axetil are considered to be interfere, while metronidazole can be considered as non-interfere.

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Paper-Based Multiplexed Colorimetric Device for the Simultaneous Detection of Salivary Biomarkers

Biosensors ◽

10.3390/bios11110443 ◽

2021 ◽

Vol 11 (11) ◽

pp. 443

Author(s):

Tania Pomili ◽

Paolo Donati ◽

Pier Paolo Pompa

Keyword(s):

Color Change ◽

Colorimetric Detection ◽

Simultaneous Detection ◽

Spectral Shift ◽

Fully Integrated ◽

Salivary Biomarkers ◽

Colorimetric Response ◽

Test Zone ◽

One Step ◽

Pre Treatment

In this study, we describe a monolithic and fully integrated paper-based device for the simultaneous detection of three prognostic biomarkers in saliva. The pattern of the proposed multiplexed device is designed with a central sample deposition zone and three identical arms, each containing a pre-treatment and test zone. Its one-step fabrication is realized by CO2 laser cutting, providing remarkable parallelization and rapidity (ca. 5 s/device). The colorimetric detection is based on the sensitive and selective target-induced reshaping of plasmonic multibranched gold nanoparticles, which exhibit a clear spectral shift (and blue-to-pink color change) in case of non-physiological concentrations of the three salivary biomarkers. A rapid and multiplexed naked-eye or smartphone-based readout of the colorimetric response is achieved within 10 min. A prototype kit for POCT testing is also reported, providing robustness and easy handling of the device.

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A Multiplex PCR for Rapid Identification of Shiga-Like Toxin-Producing Escherichia coli O157:H7 Isolated from Foods‡

Journal of Food Protection ◽

10.4315/0362-028x-59.6.570 ◽

1996 ◽

Vol 59 (6) ◽

pp. 570-576 ◽

Cited By ~ 23

Author(s):

MING Y. DENG ◽

PINA M. FRATAMICO

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Dna Sequences ◽

Bacterial Species ◽

Colorimetric Detection ◽

Food Samples ◽

Enterohemorrhagic Escherichia Coli ◽

Experimental Conditions ◽

Serological Tests ◽

E Coli

For rapid and specific identification of enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 isolated from food samples, experimental conditions for a multiplex polymerase chain reaction (PCR) were optimized and a multiple digoxigenin (DIG)-labeled oligonucleotide probe hybridization (DLOPH) assay was developed. A suspect colony from MacConkey sorbitol agar containing 5-bromo-4-chloro-3-indoxyl-β-d-glucuronide (MSA-BCIG) was used for the multiplex PCR. Three different DNA sequences of E. coli O157:H7 were amplified simultaneously in the PCR: a specific fragment of an attaching and effacing gene (eae gene), conserved sequences of Shiga-like toxins (SLT) I and II, and a fragment of the 60-MDa plasmid. The identities of PCR products were confirmed by hybridization using DIG-labeled internal oligonucleotide probes and colorimetric detection with anti-DIG Fab fragments conjugated to alkaline phosphatase. This method yielded positive results with all reference strains of EHEC serogroup O157, including serotypes O157:H7, O157:NM, and O157:H−, and negative results were obtained with all strains of nontoxigenic E. coli serogroup O157, other serotypes of E. coli, and other bacterial species. The detection limit of the method was 65 colony-forming units (CFU) of E. coli O157:H7. All 29 cultures of EHEC O157:H7 isolated from meat samples and identified by biochemical and serological tests were positive in the multiplex PCR. EHEC O157:H7 was identified from all of 70 experimentally inoculated ground beef and milk samples which had initial inocula of 4 to 9 CFU/g (ml) and were subjected to a 6-h enrichment culturing. The multiplex PCR procedure could be very useful for routine examinations of food samples for the presence of EHEC O157.

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Faculty Opinions recommendation of One-step, multiplex, real-time PCR assay with molecular beacon probes for simultaneous detection, differentiation, and quantification of human T-cell leukemia virus types 1, 2, and 3.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.713998082.789502847 ◽

2012 ◽

Author(s):

Sanjay Tyagi

Keyword(s):

T Cell ◽

Real Time Pcr ◽

Molecular Beacon ◽

Leukemia Virus ◽

Simultaneous Detection ◽

Cell Leukemia ◽

Pcr Assay ◽

Human T Cell ◽

T Cell Leukemia Virus ◽

One Step

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Calorimetric Sensor for Ethanol Using Ni2+-nitrilotriacetic Acid (NTA) Resin Immobilized Alcohol Dehydrogenase (ADH)

Current Analytical Chemistry ◽

10.2174/1573411015666190617110233 ◽

2020 ◽

Vol 16 (6) ◽

pp. 795-799

Author(s):

YongJin Li

Keyword(s):

Cost Effective ◽

Nitrilotriacetic Acid ◽

Repeated Measurements ◽

Great Promise ◽

Calorimetric Sensor ◽

Controlled Pore Glass ◽

Pore Glass ◽

One Step ◽

Immobilization Matrix ◽

Enzyme Thermistor

Background: A simple, fast and economic analytical method for the determination of ethanol is important for clinical, biological, forensic and physico-legal purposes. Methods: Ni2+-NTA resin was used as an immobilization matrix for the simple one-step purification/ immobilization of his6-tagged ADH. Different alcohols with a concentration range of 0.5-50% V/V, namely methanol, ethanol and propanol were measured using prepared ADH enzyme thermistor. The ethanol content of Tsingtao beer was tested as a real sample containing alcohol. Reproducibility and stability of prepared ADH enzyme thermistor were also investigated by repeated measurements. Results: In comparison to the controlled pore glass (a common used support for the immobilization of enzyme) used in thermal biosensor, the use of Ni2+-NTA resin not only led to simple one-step purification/ immobilization by his6-tagged ADH binding to Ni2+-NTA resin, but also made the immobilizing supports reusable. The prepared biosensor can be used to determine ethanol and methanol by the calorimetric measurement. A linear range of 1 -32% (V/V) and 2-20% (V/V) was observed for ethanol and methanol, respectively. The detection limits were 0.3% (V/V) and 1% (V/V) for ethanol and methanol, respectively. The tested ethanol concentration of Tsingtao beer was 4.5% V/V, which is comparable with the labeled alcohol by volume (ABV) 4.80%. Conclusion: Ni2+-NTA resin, as an immobilization matrix in ET sensor, provides a simple one-step purification/immobilization for His6-tagged recombinase and a reusable immobilization matrix. The prepared biosensor exhibits good repeatability and stability. Such a new biosensor shows great promise for rapid, simple, and cost-effective analysis of ethanol and methanol, both in qualitative and in quantitative tests.

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Manufacturing Processes of Solid Oxide Fuel Cell Components

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.498 ◽

2007 ◽

Vol 336-338 ◽

pp. 498-501

Author(s):

Xian Feng Jiang ◽

Min Fang Han ◽

Su Ping Peng

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Screen Printing ◽

Sol Gel ◽

Tape Casting ◽

Solid Oxide ◽

Oxide Fuel ◽

Cell Components ◽

One Step ◽

Made In

The all processes for manufacturing materials parts of solid oxide fuel cell (SOFC) are discussed in the paper. The films are made in one step by the ways of APS, VPS, EVD, which are usually used to produce the electrolyte and interconnect. The films are thin and good gas-resistance, but with relatively high cost. All parts of SOFC are made by the following ways, such as sol-gel, tape casting, tape calendaring and screen printing, which are suitable for manufacturing samples in industry with the cheapest process by co-sintered together ways.

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Chitosan-based enzyme ink for screen-printed bioanodes

RSC Advances ◽

10.1039/d1ra03277a ◽

2021 ◽

Vol 11 (33) ◽

pp. 20550-20556

Author(s):

Isao Shitanda ◽

Kanako Oda ◽

Noya Loew ◽

Hikari Watanabe ◽

Masayuki Itagaki ◽

...

Keyword(s):

Magnesium Oxide ◽

Mesoporous Carbon ◽

Screen Printing ◽

Printing Process ◽

One Step ◽

Screen Printed

Bio-composite inks based on magnesium oxide (MgO)-templated mesoporous carbon (MgOC) and chitosan cross-linked with genipin for one-step screen-printing process.

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3D Printed Microfluidic Devices for Drug Release Assays

Pharmaceutics ◽

10.3390/pharmaceutics13010013 ◽

2020 ◽

Vol 13 (1) ◽

pp. 13

Author(s):

Benzion Amoyav ◽

Yoel Goldstein ◽

Eliana Steinberg ◽

Ofra Benny

Keyword(s):

3D Printing ◽

Drug Release ◽

Particle Production ◽

Cost Effective ◽

Drug Dissolution ◽

Cytotoxicity Test ◽

High Durability ◽

One Step ◽

Cost Effective Alternative ◽

Multiple Recycling

Microfluidics research for various applications, including drug delivery, cell-based assays and biomedical research has grown exponentially. Despite this technology’s enormous potential, drawbacks include the need for multistep fabrication, typically with lithography. We present a one-step fabrication process of a microfluidic chip for drug dissolution assays based on a 3D printing technology. Doxorubicin porous and non-porous microspheres, with a mean diameter of 250µm, were fabricated using a conventional “batch” or microfluidic method, based on an optimized solid-in-oil-in-water protocol. Microspheres fabricated with microfluidics system exhibited higher encapsulation efficiency and drug content as compared with batch formulations. We determined drug release profiles of microspheres in varying pH conditions using two distinct dissolution devices that differed in their mechanical barrier structures. The release profile of the “V” shape barrier was similar to that of the dialysis sac test and differed from the “basket” barrier design. Importantly, a cytotoxicity test confirmed biocompatibility of the printed resin. Finally, the chip exhibited high durability and stability, enabling multiple recycling sessions. We show how the combination of microfluidics and 3D printing can reduce costs and time, providing an efficient platform for particle production while offering a feasible cost-effective alternative to clean-room facility polydimethylsiloxane-based chip microfabrication.

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