• Instrumental Colorimetric Analysis


The Vacu-vials® Method

To perform a test, immerse the Vacu-vials ampoule into the sample and snap off the tip (Step 1).  The correct volume of sample is automatically drawn in, filling the ampoule; a small inert gas bubble remains in the ampoule.

To facilitate mixing the sample and reagent, tilt the ampoule back and forth so the bubble travels from end to end (Step 2). In 2 minutes or less, quantify the result by placing the filled ampoule in the cell holder of an instrument set to a wavelength for optimal absorbance (Step 3).

If you use an instrument that reads absorbance, the absorbance value can be converted to concentration units with the supplied calibration equation. A calculator to convert spectrophotometer absorbance readings to test results (ppm) for all CHEMetrics instrumental test kits is posted under the "Support" tab on our website. Direct-reading instruments are available.

Vacu-vials Kits include 30 ampoules, a zero standard, accessory solution(s) (when necessary), a sample cup, and instructions.  Safety Data Sheets (SDSs) are available on CHEMetrics' website. Click HERE

The Vacu-vials ampoules are 13 mm in diameter with a tapered, pre-scored tip; color forming reagents are vacuum-sealed inside.

The Vacu-vials Test Procedure

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