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Since 1969, when
CHEMetrics
introduced the concept, the self-filling reagent ampoule has been
simplifying water testing for analysts all over the world. The key
elements of colorimetric analysis -- reagent formulation, measurement
and dispensing of the reagent, and measurement of the sample -- are all
embodied in this unique, safe, dependable package.
When the cost of performing a test is calculated, whether it's in the lab or out in the field, the key element is time - - the time it takes to get ready, the time it takes to do the actual test, and finally, the time it takes to clean up. In all of these areas, CHEMetrics' ampoules save dollars, because time-consuming chores have been eliminated by the features we build into each ampoule. We formulate the reagent in liquid form with buffers and anti-interference components and we measure the dosage for you. We also measure the sample for you and then, after the test is done, we let you walk away without glassware to clean up. All these features save you time, and that's money! Compare the ordinary test kit procedures, with their slow-dissolving tablets or powdered reagents put up in "fumble packs" to the CHEMetrics way. It will be clear that our self-filling ampoules mean savings. What about safety? Some reagents have hazardous properties - - that's unavoidable. But when you use self-filling ampoules, contact and exposure are minimized because the reagent packaged in the ampoule remains in the ampoule, even after testing is finished. That means that CHEMetrics' tests are safer to use than ordinary methods that require the analyst to handle and dispense potentially dangerous chemicals. (N.B. Caution is advised when performing any chemical operation. Some self-filling ampoule tests require the use of accessory reagents which must be added directly to the sample. Disposal of all chemical materials is subject to governmental regulation.) Colorimetric test ampoules for visual and photometric readout. The basic, snap-mix-read simplicity of the self-filling ampoule concept is available in three versions called CHEMets®, Vacu-vials® and ULR CHEMets®. CHEMets® (see diagrams above) are 100 mm long and 7 mm in diameter. They're ideal for fast, accurate testing when the analyte is in the range of 1-10 ppm (mg/L), or, by viewing lengthwise, in the 0-1 ppm range. (See also Chemets.) Vacu-vials® (see diagrams above) offer the convenience and accuracy of the self-filling ampoule in a larger diameter package designed specifically for photometric readout. The filled ampoule functions as a half inch (13 mm) diameter cell which may be read in virtually any commercial spectrophotometer or colorimeter. We offer the SAM Single Analyte Meter, the V-2000 Multi-Analyte Meter, and the VVR Multi-Analyte System for use with Vacuvials. (See also Vacu-vials.) ULR CHEMets® are longer (10-inch) versions of the self-filling ampoule. They provide a visual path length which permits the analyst to detect and measure analytes at very low (ppb) concentrations. ULRs are available for chlorine, dissolved oxygen, hydrogen peroxide and hydrazine. (See also ULR Chemets.) Auto-diluting ampoules for high range analysis. Vacuettes®
are CHEMetrics' answer to another of the analyst's headaches - -
diluting samples so that they fall within the applicable range of a
colorimetric method. Each Vacuette ampoule is a CHEMet that's
fitted with a pre-calibrated capillary pipette at the tip. When
high concentrations of analyte are to be measured, the capillary
automatically captures the proper volume of sample. The analyst
then simply snaps the tip of the ampoule in dilution water to
flush the contents of the capillary into the tube, diluting it at the
same time. Capillaries of various sizes are offered to provide
dilution ratios of 25X, 50X, 100X, and 1000X. (See also Vacuettes.)
Titration tests with self-filling ampoules. Titrets®
simplify titration tests just as CHEMets and Vacu-vials simplify
colorimetric tests. Each Titret contains a carefully measured
quantity of titrant sealed under vacuum. The sealed tip is fitted
with a miniature valve that is used to control the flow of sample into
the ampoule as the analyst performs what is known as a "reverse
titration." Sample is introduced into the ampoule in small
increments (with mixing) while the analyst watches for the color change
which signals the end-point of the titration. When that change
occurs, the ampoule is placed in an upright position and the test result
is read opposite the location of the liquid level, using a scale printed
on the side of the tube. The entire process requires only a minute
or two and avoids all the equipment hassle and clean-up associated with
ordinary titrations. (See also Titrets.)
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