Advances in Gold Nanoparticles-Based Colorimetric Aptasensors for the Detection of Antibiotics: An Overview of the Past Decade

Misuse of antibiotics has recently been considered a global issue because of its harmful effects on human health. Since conventional methods have numerous limitations, it is necessary to develop fast, simple, sensitive, and reproducible methods for the detection of antibiotics. Among numerous recently developed methods, aptasensors are fascinating because of their good specificity, sensitivity and selectivity. These kinds of biosensors combining aptamer with colorimetric applications of gold nanoparticles to recognize small molecules are becoming more popular owing to their advantageous features, for example, low cost, ease of use, on-site analysis ability using naked eye and no prerequisite for modern equipment. In this review, we have highlighted the recent advances and working principle of gold nanoparticles based colorimetric aptasensors as promising methods for antibiotics detection in different food and environmental samples (2011–2020). Furthermore, possible advantages and disadvantages have also been summarized for these methods. Finally, the recent challenges, outlook, and promising future perspectives for developing novel aptasensors are also considered.

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A Comparison of 2-part and 3-part Nanoparticle-Based Sensors

MRS Proceedings ◽

10.1557/proc-1138-ff01-05 ◽

2008 ◽

Vol 1138 ◽

Cited By ~ 1

Author(s):

Jorge Chavez ◽

Wanda J. Lyon ◽

Nancy Kelley-Loughnane ◽

Yaroslav G. Chushak ◽

Morley O. Stone

Keyword(s):

Gold Nanoparticles ◽

Interparticle Distance ◽

High Specificity ◽

Thiol Group ◽

Optical Signal ◽

Ease Of Use ◽

Short Oligonucleotide ◽

Advantages And Disadvantages ◽

Sensitivity And Selectivity ◽

Recognition Motifs

AbstractThere has long been a drive to produce sensors with ever-increasing sensitivity and selectivity, while also achieving robustness and ease of use. Nanoparticle-based sensing approaches have generated a great deal of attention and excitement, because they possess such qualities. For these assays to function properly, it requires the integration of molecular recognition motifs and materials with outstanding optical properties. Aptamers are DNA or RNA sequences that bind analytes with high specificity, which makes them a suitable choice as recognition elements. Changes in the surface plasmon resonance (SPR) of gold nanoparticles (AuNPS) as a function of interparticle distance, has been used as an optical signal to detect the presence of different species in solution by the naked eye. In this work, we coated gold nanoparticles with short oligonucleotides and aptamers for the design of sensors that can be used under different conditions, including salt concentration, pH and temperatures. Three aptamer sensors were developed using this approach 1) riboflavin, as a general indicator of biological activity, 2) ricin, a toxin that is of broad interest, and 3) theophylline, an adenosine antagonist. Our designs are based on two approaches, the first method consisted of the use of two sets of AuNPs, each coated with a short oligonucleotide complementary to a different part of the sequence of the aptamer of interest. Hybridization of the DNA-coated particles (DNA-AuNPs) with the free aptamer produced aggregates, i.e. 3-part design. The second approach consisted of the use of only two sets of DNA-AuNPs, one coated with an aptamer that contains a thiol group in its 5′ end, and the second set of AuNPs coated with a sequence complementary to part of the aptamer. Hybridization of these two sets of particles produced aggregates, i.e. 2-part design. In both cases, the presence of the analyte promoted a change in the conformation of the aptamer, which caused the dehybridization of the complementary sequences. This conformational change of the aptamer upon binding of the analyte produced the dissociation of the nanoparticle aggregates, which is translated into a change in the color of the suspensions from blue to red. In this presentation, we will compare the advantages and disadvantages associated with a 3-part versus a 2-part nanoparticle-oligonucleotide reporting assay.

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Overview on the Liquid Metal Battery for Grid-Level Large-Scale Energy Storage

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.723.572 ◽

2016 ◽

Vol 723 ◽

pp. 572-578

Author(s):

Li Fu ◽

Qi Chi Le ◽

Xi Bo Wang ◽

Xuan Liu ◽

Wei Tao Jia

Keyword(s):

Energy Storage ◽

Liquid Metal ◽

Large Scale ◽

Low Cost ◽

Advantages And Disadvantages ◽

Comprehensive Comparison ◽

Development And Utilization ◽

Working Principle ◽

Liquid Metal Battery ◽

Grid Level

In recent years, the development and utilization of renewable generation have attracted more and more attention, and the grid puts forward higher requirements to the energy storage technology, especially for security, stability and reliability. The liquid metal battery (LMB) consists of two liquid metal electrodes and a molten salt electrolyte, which will be segregated into three liquid layers naturally. Being low-cost and long-life, it is regarded as the best choice for grid-level large-scale energy storage. This paper describes the main structure and working principle of the LMB, analyzes the advantages and disadvantages of the LMB when compared with the traditional batteries, and explores the feasibility and economy when it is used as a kind of large-scale energy storage applied in the power grid. The paper also makes a comprehensive comparison on the performance of several LMBs, and points out the LMB’s research and development in the future.

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Design and Study of Hydroelectric Power Plant by Using Overshot and Undershot Waterwheels

International Journal of Energy Optimization and Engineering ◽

10.4018/ijeoe.2019100103 ◽

2019 ◽

Vol 8 (4) ◽

pp. 39-59

Author(s):

Jamal A. Hameed ◽

Amer T Saeed ◽

Mugdad H. Rajab

Keyword(s):

Rural Areas ◽

River Flow ◽

Low Cost ◽

Mechanical Energy ◽

Hydroelectric Power Plant ◽

Electrical Energy ◽

Hydroelectric Power ◽

Bridge Rectifier ◽

Working Principle ◽

Harmful Effects

This article gives an idea about the operative use of waterwheels in a river flow, which offers power generation with low cost. It also defines the working principle, calculations and design, challenges and applications beside the future scope of using Overshot and undershot waterwheels. In order to cover the enlarged demand for power in rural areas of Iraq, generated hydropower from waterwheels are one of the most promising solutions to produce electricity. Modern water wheels are made from steel which promising no harmful effects on the environment. In this research, two types of water wheels (Overshot and Undershot) are used to produce the electricity through fastening the waterwheel to a generator with the support of a belt and pulley arrangement, so the electrical energy resulted from mechanical energy. The full bridge rectifier is used to transfer electricity in its most effectual form while the regulator is used to adjust the current.

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REVIEW OF SATELLITE-FREE NAVIGATION SYSTEMS

Issues of radio electronics ◽

10.21778/2218-5453-2018-11-20-24 ◽

2018 ◽

pp. 20-24

Author(s):

M. K. Savkin ◽

A. R. Filatov

Keyword(s):

Satellite Navigation ◽

Navigation Systems ◽

Military Operations ◽

Advantages And Disadvantages ◽

Working Principle ◽

Satellite Signal ◽

Satellite Navigation Systems ◽

Insufficient Number

Nowadays majority of navigation methods, used in unmanned flying vehicles, are based on satellite navigation systems, such as GPS or GLONASS, or are amplified with them. But hardware, that uses such systems, can’t work in difficult conditions, for example causes by relief: with insufficient number of satellites or at low satellite signal. Satellite navigation systems are vulnerable for methods of radio defense: satellite signal can be deadened or replaced. That is why such systems usage is unacceptable while critical missions during military operations, emergency or reconnaissance. The article briefly describes components used for building alternative satellite-free navigation systems for flying vehicles. For each component its purpose and brief description of working principle are given, advantages and disadvantages are considered.

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Reinforcement of Recycled Aggregate by Microbial-Induced Mineralization and Deposition of Calcium Carbonate—Influencing Factors, Mechanism and Effect of Reinforcement

Crystals ◽

10.3390/cryst11080887 ◽

2021 ◽

Vol 11 (8) ◽

pp. 887

Author(s):

Chunhua Feng ◽

Buwen Cui ◽

Haidong Ge ◽

Yihong Huang ◽

Wenyan Zhang ◽

...

Keyword(s):

Calcium Carbonate ◽

Global Economy ◽

Low Cost ◽

High Water ◽

Strengthening Mechanism ◽

Recycled Aggregate ◽

Strengthening Effect ◽

Calcium Carbonate Precipitation ◽

Environmental Friendliness ◽

Advantages And Disadvantages

Recycled aggregate is aggregate prepared from construction waste. With the development of a global economy and people’s attention to sustainable development, recycled aggregate has shown advantages in replacing natural aggregate in the production of concrete due to its environmental friendliness, low energy consumption, and low cost. Recycled aggregate exhibits high water absorption and a multi-interface transition zone, which limits its application scope. Researchers have used various methods to improve the properties of recycled aggregate, such as microbially induced calcium carbonate precipitation (MICP) technology. In this paper, the results of recent studies on the reinforcement of recycled aggregate by MICP technology are synthesized, and the factors affecting the strengthening effect of recycled aggregate are reviewed. Moreover, the strengthening mechanism, advantages and disadvantages of MICP technology are summarized. After the modified treatment, the aggregate performance is significantly improved. Regardless of whether the aggregate was used in mortar or concrete, the mechanical properties of the specimens were clearly improved. However, there are some issues regarding the application of MICP technology, such as the use of an expensive culture medium, a long modification cycle, and untargeted mineralization deposition. These difficulties need to be overcome in the future for the industrialization of regenerated aggregate materials via MICP technology.

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Imaging in Propeller Flap Surgery

Seminars in Plastic Surgery ◽

10.1055/s-0040-1715159 ◽

2020 ◽

Vol 34 (03) ◽

pp. 145-151

Author(s):

Shimpei Ono ◽

Hiroyuki Ohi ◽

Rei Ogawa

Keyword(s):

Low Cost ◽

Three Dimensional ◽

Duplex Sonography ◽

Computed Tomographic Angiography ◽

Ease Of Use ◽

Computed Tomographic ◽

Imaging Tool ◽

Preoperative Mapping ◽

Flap Design ◽

Tomographic Angiography

AbstractSince propeller flaps are elevated as island flaps and most often nourished by a single perforator nearby the defect, it is challenging to change the flap design intraoperatively when a reliable perforator cannot be found where expected to exist. Thus, accurate preoperative mapping of perforators is essential in the safe planning of propeller flaps. Various methods have been reported so far: (1) handheld acoustic Doppler sonography (ADS), (2) color duplex sonography (CDS), (3) perforator computed tomographic angiography (P-CTA), and (4) magnetic resonance angiography (MRA). To facilitate the preoperative perforator assessment, P-CTA is currently considered as the gold standard imaging tool in revealing the three-dimensional anatomical details of perforators precisely. Nevertheless, ADS remains the most widely used tool due to its low cost, faster learning, and ease of use despite an undesirable number of false-positive results. CDS can provide hemodynamic characteristics of the perforator and is a valid and safer alternative particularly in patients in whom ionizing radiation and/or contrast exposure should be limited. Although MRA is less accurate in detecting smaller perforators of caliber less than 1.0 mm and the intramuscular course of perforators at the present time, MRA is expected to improve in the future due to the recent developments in technology, making it as accurate as P-CTA. Moreover, it provides the advantage of being radiation-free with fewer contrast reactions.

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Liquid marble based digital microfluidics – fundamentals and applications

Lab on a Chip ◽

10.1039/d0lc01290d ◽

2021 ◽

Author(s):

Chin Hong Ooi ◽

Raja Vadivelu ◽

Jing Jin ◽

Sreejith Kamalalayam Rajan ◽

Pradip Singha ◽

...

Keyword(s):

Low Cost ◽

Digital Microfluidics ◽

Ease Of Use ◽

Liquid Marbles ◽

Liquid Marble

Liquid marbles are droplets with volume typically on the order of microliters coated with hydrophobic powder. The versatility, ease of use and low cost make liquid marbles an attractive platform...

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Molecularly Imprinted Polymers Combined with Electrochemical Sensors for Food Contaminants Analysis

Molecules ◽

10.3390/molecules26154607 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4607

Author(s):

Dounia Elfadil ◽

Abderrahman Lamaoui ◽

Flavio Della Pelle ◽

Aziz Amine ◽

Dario Compagnone

Keyword(s):

Food Safety ◽

Molecularly Imprinted Polymers ◽

Electrochemical Sensors ◽

Low Cost ◽

Electrochemical Analysis ◽

Ease Of Use ◽

Electrochemical Sensing ◽

Food Contaminants ◽

Molecularly Imprinted ◽

Imprinted Polymers

Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given.

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Review of Electrochemical DNA Biosensors for Detecting Food Borne Pathogens

Sensors ◽

10.3390/s19224916 ◽

2019 ◽

Vol 19 (22) ◽

pp. 4916 ◽

Cited By ~ 4

Author(s):

Qiaoyun Wu ◽

Yunzhe Zhang ◽

Qian Yang ◽

Ning Yuan ◽

Wei Zhang

Keyword(s):

Pathogen Detection ◽

Low Cost ◽

Electrochemical Techniques ◽

Ease Of Use ◽

Detection Methods ◽

Future Research ◽

Dna Biosensors ◽

Food Borne Pathogens ◽

Chip Technology ◽

Food Borne

The vital importance of rapid and accurate detection of food borne pathogens has driven the development of biosensor to prevent food borne illness outbreaks. Electrochemical DNA biosensors offer such merits as rapid response, high sensitivity, low cost, and ease of use. This review covers the following three aspects: food borne pathogens and conventional detection methods, the design and fabrication of electrochemical DNA biosensors and several techniques for improving sensitivity of biosensors. We highlight the main bioreceptors and immobilizing methods on sensing interface, electrochemical techniques, electrochemical indicators, nanotechnology, and nucleic acid-based amplification. Finally, in view of the existing shortcomings of electrochemical DNA biosensors in the field of food borne pathogen detection, we also predict and prospect future research focuses from the following five aspects: specific bioreceptors (improving specificity), nanomaterials (enhancing sensitivity), microfluidic chip technology (realizing automate operation), paper-based biosensors (reducing detection cost), and smartphones or other mobile devices (simplifying signal reading devices).

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Review on stationary phases and coating methods of MEMs gas chromatography columns

Reviews in Analytical Chemistry ◽

10.1515/revac-2020-0102 ◽

2020 ◽

Vol 39 (1) ◽

pp. 247-259

Author(s):

Liu Yang ◽

Molin Qin ◽

Junchao Yang ◽

Genwei Zhang ◽

Jiana Wei

Keyword(s):

Gas Chromatography ◽

Microelectromechanical Systems ◽

Stationary Phases ◽

Preparation Methods ◽

Site Analysis ◽

Advantages And Disadvantages ◽

Coating Methods ◽

On Line ◽

Inorganic Adsorbents ◽

Gas Chromatography Columns

Abstract Gas chromatography (GC) is an important and widely used technique for separation and analysis in the field of analytical chemistry. Micro gas chromatography has been developed in response to the requirement for on-line analysis and on-site analysis. At the core of micro gas chromatography, microelectromechanical systems (MEMs) have the advantages of small size and low power consumption. This article introduces the stationary phases of micro columns in recent years, including polymer, carbon materials, silica, gold nanoparticles, inorganic adsorbents and ionic liquids. Preparation techniques ranging from classical coating to unusual sputtering of stationary phases are reviewed. The advantages and disadvantages of different preparation methods are analyzed. The paper introduces the separation characteristics and application progress of MEMs columns and discusses possible developments.

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