Detection of trace arsenic in drinking water: challenges and opportunities for microfluidics

2015 ◽  
Vol 1 (4) ◽  
pp. 426-447 ◽  
Author(s):  
Nevetha Yogarajah ◽  
Scott S. H. Tsai
Keyword(s):  
Drinking Water ◽  
Sample Preparation ◽  
Signal Acquisition ◽  
Sample Analysis ◽  
Arsenic Detection ◽  
Challenges And Opportunities ◽  
Total Analytical System ◽  
Analytical System

Conception of a micro total analytical system (μTAS), capable of sample preparation, sample analysis, and signal acquisition, for portable trace arsenic detection.

scholarly journals Detection of trace arsenic in drinking water: challenges and opportunities for microfluidics

2021 ◽  
Author(s):  
Nevetha Yogarajah ◽  
Scott S. H. Tsai
Keyword(s):  
Drinking Water ◽  
World Health Organisation ◽  
Arsenic Contamination ◽  
Ease Of Use ◽  
World Health ◽  
Arsenic Detection ◽  
Routine Monitoring ◽  
Challenges And Opportunities ◽  
Sensitivity And Selectivity ◽  
Economic Constraints

Arsenic contamination of drinking water is a major global problem, with contamination in Bangladesh deemed most serious. Although the current World Health Organisation (WHO) maximum contamination limit (MCL) for arsenic in drinking water is 10 μg L−1, due to practical and economic constraints, the standard limit in Bangladesh and many other developing nations is 50 μg L−1. We propose that an ideal arsenic sensor, designed for routine monitoring, will have five essential qualities: sensitivity and selectivity for arsenic; speed and reliability; portability and robustness; reduced health and environmental risks; and affordability and ease of use for local technicians. It is our opinion that many of these characteristics can be accentuated by microfluidic systems. We describe candidate colorimetric, electrochemical, biological, electrophoretic, surface-sensing, and spectroscopic methods for arsenic detection; and comment on their potential for portable microfluidic adaptation. We also describe existing developments in the literature towards the ultimate creation of microfluidic total analysis systems (μTASs) for arsenic detection. The fundamental purpose of this review is to highlight the need for better portable arsenic contamination detection, and describe how microfluidic technology may be developed to address this need.

scholarly journals Detection of trace arsenic in drinking water: challenges and opportunities for microfluidics

2021 ◽  
Author(s):  
Nevetha Yogarajah ◽  
Scott S. H. Tsai
Keyword(s):  
Drinking Water ◽  
World Health Organisation ◽  
Arsenic Contamination ◽  
Ease Of Use ◽  
World Health ◽  
Arsenic Detection ◽  
Routine Monitoring ◽  
Challenges And Opportunities ◽  
Sensitivity And Selectivity ◽  
Economic Constraints

Arsenic contamination of drinking water is a major global problem, with contamination in Bangladesh deemed most serious. Although the current World Health Organisation (WHO) maximum contamination limit (MCL) for arsenic in drinking water is 10 μg L−1, due to practical and economic constraints, the standard limit in Bangladesh and many other developing nations is 50 μg L−1. We propose that an ideal arsenic sensor, designed for routine monitoring, will have five essential qualities: sensitivity and selectivity for arsenic; speed and reliability; portability and robustness; reduced health and environmental risks; and affordability and ease of use for local technicians. It is our opinion that many of these characteristics can be accentuated by microfluidic systems. We describe candidate colorimetric, electrochemical, biological, electrophoretic, surface-sensing, and spectroscopic methods for arsenic detection; and comment on their potential for portable microfluidic adaptation. We also describe existing developments in the literature towards the ultimate creation of microfluidic total analysis systems (μTASs) for arsenic detection. The fundamental purpose of this review is to highlight the need for better portable arsenic contamination detection, and describe how microfluidic technology may be developed to address this need.

Urban water supply in India: status, reform options and possible lessons

Water Policy ◽  
2009 ◽  
Vol 11 (4) ◽  
pp. 442-460 ◽  
Author(s):  
David McKenzie ◽  
Isha Ray
Keyword(s):  
Drinking Water ◽  
Low Income ◽  
Urban Areas ◽  
Family Health ◽  
Urban Water ◽  
Water Sector ◽  
Metropolitan Regions ◽  
Secondary Sources ◽  
Human Needs ◽  
Challenges And Opportunities

Large numbers of households in cities around the developing world do not have access to one of the most basic of human needs–a safe and reliable supply of drinking water. This paper uses the experience of India as a lens through which to view the problems of access to water in urban areas and the various options available for reform. Using two sets of data from the National Family Health Survey, as well as published and unpublished secondary sources, the paper presents the status of access to drinking water in urban India, the performance of India's urban water sector compared to other Asian metropolitan regions and the reform efforts that are under way in several Indian cities. A review of these ongoing reforms illustrates some of the political economy challenges involved in reforming the water sector. Based on this analysis, we draw out directions for more effective research, data collection and policy reform. While each country faces unique challenges and opportunities, the scope and range of the Indian experience provides insights and caveats for many low-income nations.

scholarly journals Micropollutants in wastewater and their degradation by ferrates (VI)

2018 ◽  
Vol 11 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Emília Kubiňáková ◽  
Lucia Fašková ◽  
Eva Králiková ◽  
Ján Híveša ◽  
Tomáš Mackuľak
Keyword(s):  
Drinking Water ◽  
High Performance ◽  
Advanced Oxidation Processes ◽  
Wastewater Treatment Plants ◽  
Water Sources ◽  
Potassium Ferrate ◽  
Organic Micropollutants ◽  
Sample Analysis ◽  
Inorganic Pollutants ◽  
Removal Processes

Abstract In recent years, the occurrence of micropollutants (MPs) in sewage-, surface-, ground- and drinking water, and their removal processes are widely discussed. The content of various chemical organic/inorganic pollutants (pharmaceuticals, drugs, pesticides, hormones, heavy metals etc.) has increased over the years. Most of these compounds are not eliminated or biotransformed in traditional wastewater treatment plants. Several advanced oxidation processes (AOPs) for the removal of resistant micropollutants from water sources have been studied. Ferrate (VI) has aroused interest as an alternative oxidizing agent in drinking water preoxidation treatment. Electrochemically prepared potassium ferrate was used to remove the studied organic micropollutants. The effect of ferrate on two widely occurring organic micropollutants in water sources, carbamazepine and caffeine, was investigated. High performance liquid chromatography (HPLC) was used for sample analysis.

scholarly journals Ultrastructure expansion microscopy in Trypanosoma brucei

Open Biology ◽  
2021 ◽  
Vol 11 (10) ◽  
Author(s):  
Ana Kalichava ◽  
Torsten Ochsenreiter
Keyword(s):  
Endoplasmic Reticulum ◽  
Sample Preparation ◽  
Trypanosoma Brucei ◽  
Basal Body ◽  
Microscopic Imaging ◽  
Future Studies ◽  
Challenges And Opportunities ◽  
A Cell ◽  
Isotropic Expansion ◽  
Physical Expansion

The recently developed ultrastructure expansion microscopy (U-ExM) technique allows us to increase the spatial resolution within a cell or tissue for microscopic imaging through the physical expansion of the sample. In this study, we validate the use of U-ExM in Trypanosoma brucei measuring the expansion factors of several different compartments/organelles and thus verify the isotropic expansion of the cell. We furthermore demonstrate the use of this sample preparation protocol for future studies by visualizing the nucleus and kDNA, as well as proteins of the cytoskeleton, the basal body, the mitochondrion and the endoplasmic reticulum. Lastly, we discuss the challenges and opportunities of U-ExM.

Automated Urease-Chromous Method for Determining Nitrogen in Fertilizers

1979 ◽  
Vol 62 (3) ◽  
pp. 503-508 ◽  
Author(s):  
Larry L Wall ◽  
Charles W Gehrke
Keyword(s):  
Sample Preparation ◽  
Sampling Rate ◽  
Screening Method ◽  
Colorimetric Method ◽  
Diammonium Phosphate ◽  
Automated Method ◽  
Relative Standard ◽  
Single Method ◽  
Analytical System ◽  
And Control

Abstract An automated urease-chromous colorimetric method (AUCM) has been developed for determining nitrogen in fertilizers. The method is applicable to fertilizer samples that contain only ammoniacal, nitrate, and urea nitrogen. The concept of this method, combining nitrate reduction and enzymatic urea hydrolysis to produce a single method for total nitrogen, is new. The AUCM is an almost totally automated method with only an acidic dissolution step as the manual sample preparation. The urea is hydrolyzed to ammonia and carbon dioxide with urease, and the nitrate is reduced to ammonia with chromous ion within the continuous flow analytical system. The final step, also within the analytical system, is the spectrophotometric measurement of the ammonia, employing the ammonia-salicylate-hypochlorite chemistry. The sampling rate is 30 samples/hr. The method is not applicable to fertilizer samples containing refractory organic nitrogen forms, water-insoluble nitrogen, or significant levels of biuret. The average per cent nitrogen recovery by the AUCM for ammonium nitrate-diammonium phosphate bulk-blended fertilizer samples was 99.7, suspensions and liquids 99.7, urea fertilizers 97.8, and urea-diammonium phosphate bulk blends 98. The relative standard deviation for the analytical system was 0.40%, and for the method, 0.70%. The sample preparation is short and simple. This method offers many advantages as a screening method for fertilizer industry and control laboratories.

Measurement of nitrogen monoxide levels in gas flows with a micro total analytical system based on LTCC

2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000152-000158
Author(s):  
Thomas Geiling ◽  
Tilo Welker ◽  
Heike Bartsch ◽  
Jens Müller
Keyword(s):  
Nitrogen Monoxide ◽  
Life Time ◽  
Gas Flows ◽  
Atmospheric Concentration ◽  
Chemiluminescent Reaction ◽  
Total Analytical System ◽  
Analytical System ◽  
High Degree ◽  
Concentration Levels ◽  
The Ideal

The measurement of nitrogen monoxide (NO) concentration levels is a vital aspect of environmental analysis and the so called CHNS analysis. The chemiluminescent reaction with ozone in the gas phase is a well-established method for the measurement of atmospheric concentration levels in the range from 4 ppb up to 100 ppm. In this contribution we present the design of a so called micro total analytical system (μTAS) for NO measurements designed in ceramic. Low temperature co-fired ceramics (LTCC) have proven to be the ideal technology, since they offer high chemical and thermal stability as well as high degree of freedom of design. The article gives an overview of the design process with emphasis on manufacture of the components and technological challenges regarding life-time.

Factors Affecting the Genotoxicity of Drinking Water

2012 ◽  
Vol 518-523 ◽  
pp. 922-927
Author(s):  
Zhi Zhen Xu ◽  
Dong Sheng Wang ◽  
Rong Zhang ◽  
Shi Chuan Tang
Keyword(s):  
Drinking Water ◽  
Sample Preparation ◽  
Acid Solution ◽  
Aquatic Ecosystem ◽  
Ammonia Nitrogen ◽  
Solution Ph ◽  
Factors Affecting ◽  
Chlorine Disinfection ◽  
Umu Test ◽  
Genotoxic Compounds

The genotoxicity of drinking water have received increased attention in recent years to assess aquatic ecosystem safety. The factors affecting the genotoxicity of drinking water, including sample preparation, the concentration of bromide and ammonia nitrogen (NH3-N), were investigated using umu test. The result showed that sample preparation and bromide could significantly influence the genotoxicity of drinking water. During sample preparation, 1 and 2 L waters concentrated were suitable for umu test and the highest yield for genotoxic compounds was obtained from acid solution (pH 2) when ethyl acetate served as the eluant. Bromide could substantially increase the genotoxicity of drinking water after chlorine disinfection. The genotoxicity of drinking water could not be increased with increasing NH3-N concentration.

Sign in / Sign up

Export Citation Format

Share Document