Mobile-phone-based colourimetric analysis for determining nitrite content in water

2018 ◽  
Vol 15 (7) ◽  
pp. 403 ◽  
Author(s):  
Chanida Puangpila ◽  
Jaroon Jakmunee ◽  
Somkid Pencharee ◽  
Wipada Pensrisirikul
Keyword(s):  
Mobile Phone ◽  
Water Samples ◽  
Diazonium Salt ◽  
Field Measurements ◽  
Cost Effective ◽  
Environmental Water ◽  
Sulfanilic Acid ◽  
Calibration Graph ◽  
Nitrite Ion ◽  
Griess Reaction

Environmental contextA widespread pollutant in groundwater, rivers and lakes is nitrite, which is commonly determined batchwise by using colourimetry. The batchwise method, however, requires relatively large and expensive instrumentation, and hence is unsuitable for in-field measurements. This work introduces a simple and portable colourimetric analyser based on a mobile-phone camera for monitoring nitrite concentrations in environmental water samples. AbstractA cost-effective and portable colourimetric analyser installed on a mobile phone was used to measure nitrite in water samples in Chiang Mai City, Thailand. The colourimetric detection was based on the Griess reaction, in which nitrite ion reacts with sulfanilic acid under acidic conditions to produce a diazonium salt that further reacts with N-(1-naphthyl)-ethylenediamine dihydrochloride to form a red–violet azo dye. Under controlled conditions using a light-tight box with LED flash lights, images of the red–violet solution were captured using a built-in camera and further analysed by a program, Panalysis, on the mobile phone. The calibration graph was created by measuring the red colour intensity of a series of standard nitrite solutions from 0.09–1.8 mg N L−1. The calibration equation was then automatically stored for nitrite analysis. The results demonstrated good performance of the mobile phone analyser as an analytical instrument. The accuracy (RE <4%) and precision (RSD ≤ 1%, intra- and inter-day) were also obtained with a detection limit of 0.03 mg N L−1 and a sample throughput of 40 samples per hour. Our results establish this simple, inexpensive and portable device as a reliable in-field monitor of nitrite in environmental waters.

On-Site Monitoring of Steroid Hormones in Environmental Waters with a Low-Cost, Integrated Polymer Lab-on-Chip Device

2013 ◽  
Vol 448-453 ◽  
pp. 396-401
Author(s):  
Nuno Miguel Matos Pires ◽  
Tao Dong
Keyword(s):  
Steroid Hormones ◽  
Optical Sensors ◽  
Water Samples ◽  
Low Cost ◽  
Cost Effective ◽  
Environmental Water ◽  
Lab On Chip ◽  
Gold Thin Film ◽  
Site Monitoring ◽  
On Chip

Routine analysis of steroid hormones in environmental water samples demands for cost-effective tools that can detect multiple targets simultaneously. This study reports a high-throughput polymer platform integrated to polymer optical sensors for on-site monitoring of hormones in water. This opto-microfluidic device concept is fully compatible to low-cost fabrication methods. A competitive chemiluminescence immunoassay was performed onto gold thin film coated chambers, and a detection resolution of roughly 0.2 ng/mL was obtained using 17β-estradiol as the model target. Furthermore, the integrated polymer platform showed good recovery for the estradiol target when spiked in surface water samples.

Hollow-fiber ultrafiltration ofCryptosporidium parvumoocysts from a wide variety of 10-L surface water samples

2002 ◽  
Vol 48 (6) ◽  
pp. 542-549 ◽  
Author(s):  
Ryan C Kuhn ◽  
Kevin H Oshima
Keyword(s):  
Surface Water ◽  
Hollow Fiber ◽  
Water Samples ◽  
Cost Effective ◽  
Environmental Water ◽  
Cryptosporidium Oocysts ◽  
Cost Effective Alternative ◽  
High Turbidity ◽  
Surface Water Samples ◽  
Better Than

An optimized hollow-fiber ultrafiltration system (50 000 MWCO) was developed to concentrate Cryptosporidium oocysts from 10-L samples of environmental water. Seeded experiments were conducted using a number of surface-water samples from the southwestern U.S.A. and source water from four water districts with histories of poor oocyst recovery. Ultrafiltration produced a mean recovery of 47.9% from 19 water samples (55.3% from 39 individual tests). We also compared oocyst recoveries using the hollow-fiber ultrafiltration system with those using the Envirochek filter. In limited comparison tests, the hollow-fiber ultrafiltration system produced recoveries similar to those of the Envirochek filter (hollow fiber, 74.1% (SD = 2.8); Envirochek, 71.9% (SD = 5.2)) in low-turbidity (3.9 NTU) samples and performed better than the Envirochek filter in high-turbidity (159.0 NTU) samples (hollow fiber, 27.5%; Envirochek, 0.4%). These results indicate that hollow-fiber ultrafiltration can efficiently recover oocysts from a wide variety of surface waters and may be a cost-effective alternative for concentrating Cryptosporidium from water, given the reusable nature of the filter.Key words: Cryptosporidium, ultrafiltration, oocyst.

Studies evaluating the applicability of utilising the same concentration techniques for the detection of protozoan parasites and viruses in water

1995 ◽  
Vol 31 (5-6) ◽  
pp. 417-423 ◽  
Author(s):  
R. Kfir ◽  
C. Hilner ◽  
M. du Preez ◽  
B. Bateman
Keyword(s):  
Water Samples ◽  
Tap Water ◽  
Cost Effective ◽  
Environmental Water ◽  
Similar Efficacy ◽  
Sample Volume ◽  
Water Recovery ◽  
Protozoan Parasites ◽  
Cartridge Filter ◽  
Giardia Muris

In this study concentration techniques regularly used for viral detection, i.e. flat-bed ultrafiltration and Filterite cartridge filtration, were evaluated for their efficacies in the recovery of protozoan parasites from water. Recovery of cysts was studied using tap water seeded with Giardia muris cysts and compared to methods designed for the detection of protozoan parasites. Recovery of cysts utilizing 1.2µm membrane filters was 11.1% (4.5-23%) compared to 11.6% (2.7-25.5%) with ultrafiltration (pore size 46-50 Å, with a molecular cut off of 50 000 daltons). Comparison of these methods for the isolation of Giardia cysts and Cryptosporidium oocysts from environmental water samples also indicated a similar efficacy. The recovery of cysts from 1001 of seeded samples using a Cuno wynd cartridge filter was 12.2% (1.6-46%) compared to 13.4% (5-24.2%) using a Filterite cartridge filter. Although the results indicated similar recovery efficacies for these two methods, use of Filterite resulted in a more consistent recovery rate. This study also indicated that the use of cartridge filters for the processing of large volume water samples (1001) showed a slightly better recovery efficacy than the flat-bed filtration technique which limits sample volume to about 101. This study shows that concentration techniques utilised for the isolation of enteric viruses can also be applied for the detection of protozoan parasites from water. This procedure allows for co-analysis of both viruses and protozoan parasites and provides a more rapid and cost-effective evaluation of water quality.

scholarly journals Cost-Effective Tween 80-Capped Copper Nanoparticles for Ultrasensitive Colorimetric Detection of Thiram Pesticide in Environmental Water Samples

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Nguyen Tuan Anh ◽  
Ngo Xuan Dinh ◽  
Hoang Van Tuan ◽  
Tran Hung Thuan ◽  
Le Minh Tung ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Water Samples ◽  
Limit Of Detection ◽  
Colorimetric Detection ◽  
Critical Role ◽  
Tween 80 ◽  
Cost Effective ◽  
Environmental Water ◽  
Environmental Water Samples ◽  
Colorimetric Probe

Thiram plays a critical role in protecting fruits and vegetables from damage by various crop diseases, but its residues significantly affect the environment, such as soil and water pollution, and becoming a serious threat to human health. Herein, Tween 80-capped copper nanoparticles (Tween 80-CuNPs) were developed as a convenient and low-cost colorimetric probe for selective detection of thiram pesticide. In the presence of thiram, the color of Tween 80-capped CuNPs changed from dark brown to olive green and colorless at high thiram concentrations. The Tween 80-capped CuNPs-based colorimetric probe exhibited good selectivity and high sensitivity (LOD about 0.17 μM) with a high linearity level in the calibration range of 0.5–25 μM of thiram concentrations. The thiram limit of detection (LOD) of proposed sensor is lower than the maximum residue limit (MRL) regulated by the governments of EU and Vietnam. Moreover, the proposed sensor was successfully applied to determine thiram in tap water with percentage recovery of 98-107% and high repeatability ( RSD = 1.9 % ). The obtained results indicated that Tween 80-capped CuNPs would become a cost-effective sensing platform for ultrahigh-sensitive thiram determination in the environmental water samples.

Detection and quantification ofLegionella pneumophilain water samples using competitive PCR

2006 ◽  
Vol 52 (6) ◽  
pp. 584-590 ◽  
Author(s):  
Priscilla Declerck ◽  
Jonas Behets ◽  
Elke Lammertyn ◽  
Ilya Lebeau ◽  
Jozef Anné ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Water Samples ◽  
Cooling Tower ◽  
Tap Water ◽  
Cost Effective ◽  
Culture Method ◽  
Environmental Water ◽  
Competitive Pcr ◽  
Promising Alternative ◽  
Standard Culture

The presence of high levels of Legionella pneumophila in man-made aquatic systems correlates with the incidence of nosocomial Legionnaires' disease. This requires a rapid, reliable, and sensitive quantification of L. pneumophila concentrations in suspected water systems. In this research, a homologous competitor was developed and evaluated in a L. pneumophila competitive polymerase chain reaction (cPCR) to quantify this human pathogen in a quick, cost-effective, and reliable way. Accuracy of cPCR was evaluated by analyzing cooling tower and tap water samples spiked with known concentrations of L. pneumophila bacteria, in parallel with the standard culture method. Legionella pneumophila amounts detected and calculated from cPCR and culture correlated very well: r = 0.998, P = 0.002 for tap water and r = 0.990, P = 0.009 for cooling tower water. Nevertheless, for both kinds of water samples, mean numbers of L. pneumophila calculated from cPCR results were always higher than those obtained by culture. This study makes it clear that the rapid, sensitive, and cost-effective L. pneumophila cPCR is a promising alternative to the standard time-consuming culture method and expensive real-time PCR to enumerate L. pneumophila bacteria in environmental water samples.Key words: Legionella pneumophila, competitive PCR, cost-effective, cooling tower water, tap water, sensitive detection.

Improving Mycobacterium spp. detection in water: a new methodological proposal

2004 ◽  
Vol 4 (2) ◽  
pp. 103-106
Author(s):  
R. Santos ◽  
S. Gonçalves ◽  
F. Macieira ◽  
F. Oliveira ◽  
R. Rodrigues ◽  
...  
Keyword(s):  
Water Samples ◽  
Recovery Rate ◽  
Opportunistic Infections ◽  
Environmental Water ◽  
Environmental Water Samples ◽  
Sample Treatment ◽  
Detection Time ◽  
Fast Detection ◽  
Enrichment Step ◽  
Mycobacterium Spp

In recent years, non-tuberculous mycobacteria (NTM), once considered merely environmental saprophytes, have emerged as a major cause of opportunistic infections. There is no evidence of human-to-human transmission but they have been found in several environmental water samples. It is, therefore, of the utmost importance to develop methods of rapidly and accurately detecting non-tuberculous mycobacteria in water samples. To obtain a maximum recovery rate and a reduction of Mycobacterium spp. detection time in water samples, different decontamination, enrichment procedures and antibiotics supplements were tested before the inoculation into the Bactec® system. The proposed method of sample treatment (decrease in the decontamination time, followed for a peptone pre-enrichment step and an aztreonam and cefepime supplement) before the inoculation into the Bactec® system proved to be a good option for reliable and fast detection of Mycobacterium spp. in water samples.

The Occurrence of Male-Specific and Somatic Bacteriophages in Polluted South African Waters

1991 ◽  
Vol 24 (2) ◽  
pp. 251-254 ◽  
Author(s):  
R. Kfir ◽  
P. Coubrough ◽  
W. O. K. Grabow
Keyword(s):  
South African ◽  
Water Samples ◽  
Biological Treatment ◽  
Environmental Water ◽  
Environmental Water Samples ◽  
Resistance Pattern ◽  
Male Specific

The occurrence of somatic (F') and male-specific (F') coliphages and Salmonella phages in a variety of environmental water samples was studied using different bacterial hosts. The number of plaque-forming units (pfu) of the different bacteriophages were compared and their resistance pattern to a biological treatment (humus tank) and chlorination was evaluated. The presence of the bacteriophages in shellfish was also studied. The morphology of isolate bacteriophages was examined as well as the visibility of the different plaques formed. Coliphages were found to produce larger and clearer plaques than all other bacteriophages studied. In most of the environmental water samples coliphages outnumbered all other bacteriophages, with the exception of dam water in which higher levels of F' Salmonella phages were detected. The majority of the F' Salmonella phages were shown to be RNA bacteriophages.

Sign in / Sign up

Export Citation Format

Share Document