Eclox, which stands for Enhanced ChemiLuminescence and OXyradical test for water quality analysis, is a rapid toxicity technology that has been shown to correlate with other established toxicity tests. Rapid toxicity testing is unable to identify specific contaminants or their concentrations and instead function as a screening tool to quickly determine whether water is potentially toxic. [1] [2] [3]
Eclox ECL is a broadband enhanced chemiluminescence (ECL) assay that can be used to qualitatively assess a water sample to determine whether it has been contaminated. ECL reactions are used in a number of clinical and analytical applications and are based upon the oxidation of luminol in the presence of the enzyme horseradish peroxidase (HRP), an oxygen source, and an enhancer such as 4-iodophenol. [4]
Eclox 3 [6]
Chemiluminescence is the emission of light (luminescence) as the result of a chemical reaction. There may also be limited emission of heat. Given reactants A and B, with an excited intermediate ◊,
Water quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through treatment of the water, can be assessed. The most common standards used to monitor and assess water quality convey the health of ecosystems, safety of human contact, extent of water pollution and condition of drinking water. Water quality has a significant impact on water supply and oftentimes determines supply options.
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder or brown recluse spider.
Piperonyl butoxide (PBO) is a pale yellow to light brown liquid organic compound used as a synergist component of pesticide formulations. That is, despite having no pesticidal activity of its own, it enhances the potency of certain pesticides such as carbamates, pyrethrins, pyrethroids, and rotenone. It is a semisynthetic derivative of safrole.
Luminol (C8H7N3O2) is a chemical that exhibits chemiluminescence, with a blue glow, when mixed with an appropriate oxidizing agent. Luminol is a white-to-pale-yellow crystalline solid that is soluble in most polar organic solvents, but insoluble in water.
An assay is an investigative (analytic) procedure in laboratory medicine, mining, pharmacology, environmental biology and molecular biology for qualitatively assessing or quantitatively measuring the presence, amount, or functional activity of a target entity. The measured entity is often called the analyte, the measurand, or the target of the assay. The analyte can be a drug, biochemical substance, chemical element or compound, or cell in an organism or organic sample. An assay usually aims to measure an analyte's intensive property and express it in the relevant measurement unit.
A reducing sugar is any sugar that is capable of acting as a reducing agent. In an alkaline solution, a reducing sugar forms some aldehyde or ketone, which allows it to act as a reducing agent, for example in Benedict's reagent. In such a reaction, the sugar becomes a carboxylic acid.
An immunoassay (IA) is a biochemical test that measures the presence or concentration of a macromolecule or a small molecule in a solution through the use of an antibody (usually) or an antigen (sometimes). The molecule detected by the immunoassay is often referred to as an "analyte" and is in many cases a protein, although it may be other kinds of molecules, of different sizes and types, as long as the proper antibodies that have the required properties for the assay are developed. Analytes in biological liquids such as serum or urine are frequently measured using immunoassays for medical and research purposes.
A fecal coliform is a facultatively anaerobic, rod-shaped, gram-negative, non-sporulating bacterium. Coliform bacteria generally originate in the intestines of warm-blooded animals. Fecal coliforms are capable of growth in the presence of bile salts or similar surface agents, are oxidase negative, and produce acid and gas from lactose within 48 hours at 44 ± 0.5°C. The term thermotolerant coliform is more correct and is gaining acceptance over "fecal coliform".
The enzyme horseradish peroxidase (HRP), found in the roots of horseradish, is used extensively in biochemistry applications. It is a metalloenzyme with many isoforms, of which the most studied type is C. It catalyzes the oxidation of various organic substrates by hydrogen peroxide.
A lateral flow test (LFT), is an assay also known as a lateral flow device (LFD), lateral flow immunochromatographic assay, or rapid test. It is a simple device intended to detect the presence of a target substance in a liquid sample without the need for specialized and costly equipment. LFTs are widely used in medical diagnostics in the home, at the point of care, and in the laboratory. For instance, the home pregnancy test is an LFT that detects a specific hormone. These tests are simple and economical and generally show results in around five to thirty minutes. Many lab-based applications increase the sensitivity of simple LFTs by employing additional dedicated equipment. Because the target substance is often a biological antigen, many lateral flow tests are rapid antigen tests.
Electrochemiluminescence or electrogenerated chemiluminescence (ECL) is a kind of luminescence produced during electrochemical reactions in solutions. In electrogenerated chemiluminescence, electrochemically generated intermediates undergo a highly exergonic reaction to produce an electronically excited state that then emits light upon relaxation to a lower-level state. This wavelength of the emitted photon of light corresponds to the energy gap between these two states. ECL excitation can be caused by energetic electron transfer (redox) reactions of electrogenerated species. Such luminescence excitation is a form of chemiluminescence where one/all reactants are produced electrochemically on the electrodes.
Resazurin is a phenoxazine dye that is weakly fluorescent, nontoxic, cell-permeable, and redox‐sensitive. Resazurin has a blue to purple color above pH 6.5 and an orange color below pH 3.8. It is used in microbiological, cellular, and enzymatic assays because it can be irreversibly reduced to the pink-colored and highly fluorescent resorufin (7-Hydroxy-3H-phenoxazin-3-one). At circum-neutral pH, resorufin can be detected by visual observation of its pink color or by fluorimetry, with an excitation maximum at 530-570 nm and an emission maximum at 580-590 nm.
The ATP test is a process of rapidly measuring actively growing microorganisms through detection of adenosine triphosphate, or ATP.
Solar water disinfection, in short SODIS, is a type of portable water purification that uses solar energy to make biologically-contaminated water safe to drink. Water contaminated with non-biological agents such as toxic chemicals or heavy metals require additional steps to make the water safe to drink.
In environmental toxicology, effects range low (ERL) and effects range median (ERM) are measures of toxicity in marine sediment. They are used by public agencies in the United States in formulating guidelines in assessing toxicity hazards, in particular from trace metals or organic contaminants.
Microtox is an in vitro testing system which uses bioluminescent bacteria to detect toxic substances in different substrates such as water, air, soils and sediments. Allivibrio fischeri are non-pathogenic, marine, bacteria that luminesce as a natural part of their metabolism. When exposed to a toxic substance, the respiratory process of the bacteria is disrupted, reducing light output. Allivibrio fischeri have demonstrated high sensitivity across a wide variety of toxic substances. Response to toxicity is observed as a change in luminescence, which is a by-product of cellular respiration. This change can be used to calculate a percent inhibition of Allivibrio fischeri that directly correlates to toxicity.
Groundwater pollution occurs when pollutants are released to the ground and make their way into groundwater. This type of water pollution can also occur naturally due to the presence of a minor and unwanted constituent, contaminant, or impurity in the groundwater, in which case it is more likely referred to as contamination rather than pollution. Groundwater pollution can occur from on-site sanitation systems, landfill leachate, effluent from wastewater treatment plants, leaking sewers, petrol filling stations, hydraulic fracturing (fracking) or from over application of fertilizers in agriculture. Pollution can also occur from naturally occurring contaminants, such as arsenic or fluoride. Using polluted groundwater causes hazards to public health through poisoning or the spread of disease.
A bioassay is an analytical method to determine the potency or effect of a substance by its effect on living animals or plants, or on living cells or tissues. A bioassay can be either quantal or quantitative, direct or indirect. If the measured response is binary, the assay is quantal; if not, it is quantitative.
4-Iodophenol (p-iodophenol) is an aromatic organic compound. A colorless solid, it is one of three monoiodophenols. 4-Iodophenol undergoes a variety of coupling reactions in which the iodine substituent is replaced by a new carbon group para to the hydroxy group of the phenol. It is also used to enhance chemiluminescence for detection of cancer cells and in the Eclox assay.
