GB2576949A - Method for measuring optical brighteners in environmental water - Google Patents
Method for measuring optical brighteners in environmental water Download PDFInfo
- Publication number
- GB2576949A GB2576949A GB1814675.3A GB201814675A GB2576949A GB 2576949 A GB2576949 A GB 2576949A GB 201814675 A GB201814675 A GB 201814675A GB 2576949 A GB2576949 A GB 2576949A
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- GB
- United Kingdom
- Prior art keywords
- water
- organic solvent
- optical brighteners
- volume
- environmental
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 72
- 230000003287 optical effect Effects 0.000 title claims abstract description 42
- 230000007613 environmental effect Effects 0.000 title claims abstract description 28
- 238000000034 method Methods 0.000 title claims abstract description 20
- 239000003960 organic solvent Substances 0.000 claims abstract description 30
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims abstract description 21
- 239000003125 aqueous solvent Substances 0.000 claims abstract description 8
- 239000000203 mixture Substances 0.000 claims abstract description 7
- 239000003599 detergent Substances 0.000 claims abstract description 6
- 238000013019 agitation Methods 0.000 claims abstract description 4
- 239000003791 organic solvent mixture Substances 0.000 claims abstract description 4
- 239000002023 wood Substances 0.000 claims description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical group ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 abstract description 12
- 239000013535 sea water Substances 0.000 abstract description 11
- 238000011109 contamination Methods 0.000 abstract description 7
- 239000010865 sewage Substances 0.000 abstract description 6
- 239000013505 freshwater Substances 0.000 abstract description 5
- 239000003795 chemical substances by application Substances 0.000 abstract description 3
- 238000005259 measurement Methods 0.000 abstract description 3
- 239000011369 resultant mixture Substances 0.000 abstract description 2
- 238000012546 transfer Methods 0.000 abstract description 2
- 239000012071 phase Substances 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 2
- 230000002550 fecal effect Effects 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- TXVWTOBHDDIASC-UHFFFAOYSA-N 1,2-diphenylethene-1,2-diamine Chemical compound C=1C=CC=CC=1C(N)=C(N)C1=CC=CC=C1 TXVWTOBHDDIASC-UHFFFAOYSA-N 0.000 description 1
- 241000219000 Populus Species 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000004587 chromatography analysis Methods 0.000 description 1
- 238000003271 compound fluorescence assay Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 239000006081 fluorescent whitening agent Substances 0.000 description 1
- 238000005558 fluorometry Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002414 normal-phase solid-phase extraction Methods 0.000 description 1
- 239000012074 organic phase Substances 0.000 description 1
- 239000003444 phase transfer catalyst Substances 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/18—Water
- G01N33/1826—Organic contamination in water
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
- G01N21/77—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/40—Concentrating samples
- G01N1/4055—Concentrating samples by solubility techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/94—Investigating contamination, e.g. dust
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/18—Water
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/40—Concentrating samples
- G01N1/4055—Concentrating samples by solubility techniques
- G01N2001/4061—Solvent extraction
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
- G01N21/77—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
- G01N2021/7769—Measurement method of reaction-produced change in sensor
- G01N2021/7786—Fluorescence
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Immunology (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Plasma & Fusion (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
- Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)
Abstract
A method for measuring the concentration of optical brighteners in an environmental water source comprising: collecting a sample of water from an environmental source; adding to the sample an organic solvent that is immiscible with water, where the volume of the organic solvent is 5% or less of the volume of the water sample; adding to the water and organic solvent mixture cetyl trimethylammonium bromide as a detergent/phase-transfer agent and agitating the resultant mixture; allowing the water and organic solvent to re-separate following agitation and then removing the organic solvent from the mixture; adding the organic solvent to water or an aqueous solvent, where the volume of water or aqueous solvent is 5% or less of the volume of organic solvent; and collecting the water and detecting the presence of optical brighteners in the water via fluorescence. A preferable organic solvent is chloroform. Also claimed are: a kit for measuring the concentration of optical brighteners comprising cetyl trimethylammonium bromide; and the use of cetyl trimethylammonium bromide in a method or kit for measuring the concentration of optical brighteners in an environmental water source. Measurement of optical brighteners in fresh or sea water may be used to detect sewage contamination.
Description
(71) Applicant(s):
The Secretary of State for Defence (Incorporated in the United Kingdom) DSTL, Porton Down, Salisbury, SP4 0JQ, United Kingdom (72) Inventor(s):
Carl Nicholas Mayers (74) Agent and/or Address for Service:
DIPR Formalities Section
Poplar 2 #2214, MoD Abbey Wood (South), BRISTOL, BS34 8JH, United Kingdom (51) INT CL:
G01N 33/18 (2006.01) G01N 1/40 (2006.01)
G01N 21/64 (2006.01) (56) Documents Cited:
CN 105510112 A US 20150079692 A1
US 20110186753 A1
Water Research, vol. 43, 2009, Y. Cao et al., Evaluation of optical brightener photodecay characteristics for detection of human fecal contamination, pp. 2273-2279
Water Research, vol. 41, 2007, P. G. Hartel et al., Exposing water samples to ultraviolet light improves fluorometry for detecting human fecal contamination, pp. 3629-3642.
Journal of Chromatography A, vol. 1088, 2005, W-C Shu et al., Determination of fluorescent whitening agents in laundry detergents and surface waters by solid-phase extraction and ion-pair high-performance liquid, pp. 218-223.
Aldrich Chemistry Handbook of Fine Chemicals, 2012-2014, Sigma-Aldrich.
(58) Field of Search:
INT CL G01N
Other: WPI, EPODOC, CAS Online, XPESP, XPSPRNG, BIOSIS, MEDLINE, XPOAC, NPL, PUBCOMP, PUBSUBS, XPMISC, Internet (54) Title of the Invention: Method for measuring optical brighteners in environmental water Abstract Title: Method for measuring optical brighteners in environmental water (57) A method for measuring the concentration of optical brighteners in an environmental water source comprising: collecting a sample of water from an environmental source; adding to the sample an organic solvent that is immiscible with water, where the volume of the organic solvent is 5% or less of the volume of the water sample; adding to the water and organic solvent mixture cetyl trimethylammonium bromide as a detergent/phase-transfer agent and agitating the resultant mixture; allowing the water and organic solvent to re-separate following agitation and then removing the organic solvent from the mixture; adding the organic solvent to water or an aqueous solvent, where the volume of water or aqueous solvent is 5% or less of the volume of organic solvent; and collecting the water and detecting the presence of optical brighteners in the water via fluorescence. A preferable organic solvent is chloroform. Also claimed are: a kit for measuring the concentration of optical brighteners comprising cetyl trimethylammonium bromide; and the use of cetyl trimethylammonium bromide in a method or kit for measuring the concentration of optical brighteners in an environmental water source. Measurement of optical brighteners in fresh or sea water may be used to detect sewage contamination.
o □□ ho
Method for Measuring Optical Brighteners in Environmental Water
The present invention is concerned with improved methods for measuring the concentration of optical brighteners in water, especially in fresh or sea water as a measure of environmental contamination from sewage.
Optical brighteners are used to make paper, but also used in washing powder as a means of making laundry appear whiter: the optical brighteners improving the fluorescence under UV light. Typical optical brighteners used in washing powders include diaminostilbene dyes.
Waste (grey) water and sewage contain a high concentration of optical brighteners due to laundry waste water. Measuring the presence of optical brighteners in fresh or sea water is a common method to detect sewage contamination. This is usually achieved through sampling large volumes of water and measuring the concentration of optical brightener in those large volumes by fluorescence assay. Large volumes of water are required to be sampled because of the relatively low concentrations of optical brightener in the vast volumes of fresh and sea water on the planet.
Sampling large volumes of water is however time consuming and laborious. Improved methods are required to overcome the need to sample such large volumes of water.
The present application thus generally aims to overcome this problem, and provide methods that require smaller volumes of water for analysis of optical brighteners as a measurement of environmental contamination by sewage.
In a first aspect, the present invention provides a method for measuring the concentration of optical brighteners in an environmental water source sample comprising
i. collecting a volume of a sample of water from an environmental source, such as a river, a lake, or a sea;
ii. adding to the water a significantly smaller volume of an organic solvent, such as 5% or less of the volume of water, wherein the organic solvent is immiscible with the water;
ill. further adding to the water and organic solvent mixture the detergent cetyl trimethylammonium bromide, or a derivative thereof, and agitating the resulting mixture;
iv. allowing the water and organic solvent to re-separate following agitation, and then removing the organic solvent from the mixture;
v. adding to the organic solvent a significantly smaller volume of water, or alternatively an aqueous solvent, such as 5% or less of the volume of the organic solvent; and vi. removing the water and measuring the fluorescence of the optical brighteners in the water.
The Applicant has identified a new method by which to rapidly concentrate optical brighteners from a volume of water from an environmental source, such as a river, a lake or a sea.
It is generally known that optical brighteners are more soluble in water than in organic solvents, especially in organic solvents which are immiscible with water such as chloroform. The Applicant has however discovered that the detergent CTAB (cetyl trimethylammonium bromide) is able to act as a phase transfer catalyst for optical brighteners to allow them to move from an aqueous phase into an immiscible inorganic phase.
The organic solvent may be chloroform.
The concentration of the cetyl trimethylammonium bromide may be about 10 mM once added to the environmental water sample.
This chance discovery provides a very simple means to purify and greatly concentrate optical brighteners from environmental water sources.
In a second aspect, the present invention provides a kit for measuring the concentration of optical brighteners in an environmental water source sample, said kit comprising cetyl trimethylammonium bromide, or a derivative thereof.
In a third aspect, the present invention provides for use of cetyl trimethylammonium bromide, or derivatives thereof, in a method or kit for measuring the concentration of optical brighteners in an environmental water source.
The present invention shall now be discussed with reference to the following non-limiting example.
Example
In one experiment a large volume of seawater (multiple litres) comprising optical brighteners was placed in a flask, and cetyl trimethylammonium bromide (CTAB) added to a concentration of lOmM CTAB in the seawater. A small volume (e.g. 50 ml) of chloroform, although this could be other immiscible organic solvents, was added and the mixture agitated. The CTAB caused the optical brighteners in the seawater to partition from the aqueous (sea water) phase into the organic (chloroform) phase. The 50ml organic phase was removed to another flask, and 1 ml of water, which could also be an aqueous solvent, was added to it. Since the CTAB remained in the seawater, the optical brighteners were now able to partition into the smaller volume of water, and be measured/detected in that smaller volume of water. This process thus allows the optical brighteners in the environmental water sample to be concentrated from being in multiple litres of seawater into just a millilitre volume of water, thus enabling methods for measuring optical brighteners in environmental water samples to be more sensitive, but to also require much smaller volumes of the environmental water to be sampled.
The method has the potential to make the environmental screening of optical brighteners in the order of one thousand times more sensitive, using a cheap and commonly available reagent (CTAB) in a simple and fast protocol.
Claims (3)
- Claims1. A method for measuring the concentration of optical brighteners in an environmental water source sample comprising1. collecting a volume of a sample of water from an environmental source;ii. adding to the water a volume of an organic solvent immiscible with water, wherein the volume of the organic solvent is 5% or less of the volume of the sample of water from the environmental source;iii. further adding to the water and organic solvent mixture the detergent cetyl trimethylammonium bromide, or a derivative thereof, and agitating the resulting mixture;iv. allowing the water and organic solvent to re-separate following agitation, and then removing the organic solvent from the mixture;v. adding to the organic solvent a volume of water or a volume of an aqueous solvent, wherein the volume of the water or aqueous solvent is 5% or less of the volume of the organic solvent; and vi. removing the water to measure the fluorescence of the optical brighteners.
- 2. A kit for measuring the concentration of optical brighteners in an environmental water source sample, said kit comprising cetyl trimethylammonium bromide, or a derivative thereof.
- 3. Use of cetyl trimethylammonium bromide, or derivatives thereof, in a method or kit for measuring the concentration of optical brighteners in an environmental water source.IntellectualPropertyOfficeApplication No:GB1814675.3Examiner:Dr Richard Wood
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1814675.3A GB2576949A (en) | 2018-09-10 | 2018-09-10 | Method for measuring optical brighteners in environmental water |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1814675.3A GB2576949A (en) | 2018-09-10 | 2018-09-10 | Method for measuring optical brighteners in environmental water |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB201814675D0 GB201814675D0 (en) | 2018-10-24 |
| GB2576949A true GB2576949A (en) | 2020-03-11 |
Family
ID=63921291
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1814675.3A Withdrawn GB2576949A (en) | 2018-09-10 | 2018-09-10 | Method for measuring optical brighteners in environmental water |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2576949A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11079329B2 (en) * | 2017-09-27 | 2021-08-03 | University of North Carolina Wilmington | Human waste water and human-derived pathogen scouting tool |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111458304B (en) * | 2020-04-10 | 2023-04-18 | 海信冰箱有限公司 | Fluorescent whitening agent detection system of washing machine |
| CN113834794A (en) * | 2021-09-29 | 2021-12-24 | 浙江宏达化学制品有限公司 | Detection method for rapidly detecting quality of fluorescent whitening agent |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110186753A1 (en) * | 2010-02-02 | 2011-08-04 | Mote Marine Laboratory, Inc. | Method and apparatus for determining the presence of optical brighteners in water samples |
| US20150079692A1 (en) * | 2013-09-19 | 2015-03-19 | King Fahd University Of Petroleum And Minerals | Method of determining phenoxy herbicides in water samples by phase transfer microextraction with simultaneous derivatization and gas-chromatography mass-spectrometry analysis |
| CN105510112A (en) * | 2015-11-24 | 2016-04-20 | 长安大学 | An aqueous two-phase system and applications thereof in enrichment of a trace fluorescent agent in a facial mask |
-
2018
- 2018-09-10 GB GB1814675.3A patent/GB2576949A/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110186753A1 (en) * | 2010-02-02 | 2011-08-04 | Mote Marine Laboratory, Inc. | Method and apparatus for determining the presence of optical brighteners in water samples |
| US20150079692A1 (en) * | 2013-09-19 | 2015-03-19 | King Fahd University Of Petroleum And Minerals | Method of determining phenoxy herbicides in water samples by phase transfer microextraction with simultaneous derivatization and gas-chromatography mass-spectrometry analysis |
| CN105510112A (en) * | 2015-11-24 | 2016-04-20 | 长安大学 | An aqueous two-phase system and applications thereof in enrichment of a trace fluorescent agent in a facial mask |
Non-Patent Citations (4)
| Title |
|---|
| Aldrich Chemistry Handbook of Fine Chemicals, 2012-2014, Sigma-Aldrich. * |
| Journal of Chromatography A, vol. 1088, 2005, W-C Shu et al., "Determination of fluorescent whitening agents in laundry detergents and surface waters by solid-phase extraction and ion-pair high-performance liquid", pp. 218-223. * |
| Water Research, vol. 41, 2007, P. G. Hartel et al., "Exposing water samples to ultraviolet light improves fluorometry for detecting human fecal contamination", pp. 3629-3642. * |
| Water Research, vol. 43, 2009, Y. Cao et al., "Evaluation of optical brightener photodecay characteristics for detection of human fecal contamination", pp. 2273-2279 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11079329B2 (en) * | 2017-09-27 | 2021-08-03 | University of North Carolina Wilmington | Human waste water and human-derived pathogen scouting tool |
| US11828708B2 (en) | 2017-09-27 | 2023-11-28 | University of North Carolina Wilmington | Human waste water and human-derived pathogen scouting tool |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201814675D0 (en) | 2018-10-24 |
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