PhasePrep - Mix Solvents Instrument Brochure

(800) 572 - 6653 • Fax: (616) 396 - 7520 • 590 East 32nd Street, Holland, MI 49423 • info@resolutionsys.comwww.resolutionsys.comSolution preparation is the first operation that has to be performed for the vast majority of samples that are submitted to an analytical laboratory. Accurate solution preparation and documentation is, therefore, the foundation for the overall integrity of any analytical laboratory. The Design Scientific PhasePrep System is designed specifi-cally for this purpose.Automatic Internal Standard Addition—Save Time, Reduce CostsThe most common way of obtaining high quantitative accuracy in HPLC, GC, AA, Mass Spectrometry and other techniques is to spike an unknown concentration of a sample with a known amount of another substance—commonly known as an internal standard. After the sample is analyzed, the response to the unknown concentration is compared to the internal standard and an accurate measurement of the concentration of the substance of interest is obtained. The 3KDVHPrep Solution Preparation System saves labor while increasing accuracy when preparing solutions having an internal standard. The PhasePrep does this in five labor saving steps:Operator enters the sample number and his/her initials.1. A sample bottle is placed on the balance and the computer 2. records the weight.Operator is prompted to add the appropriate amount of solute 3. to the bottle.The computer calculates the exact amount of solvent required. 4. The solvent, with the internal standard dissolved, is added to the sample to obtain a dilution with a typical accuracy of 0.02%. The completed sample is removed and the printed sample label 5. is affixed to the bottle.Gravimetric Dilution: More Accurate than VolumetricSolutions prepared using volumetric glassware are inherently inaccu-rate because of the density change of the solvent as the laboratory changes temperature. The magnitude of this error can be understood by referring to Table 1. Since Borosilicate (Pyrex™) glassware changes volume by only 0.013% over the same temperature span, the errors caused by this volumetric change can easily be as high as 0.5%.Modern analytical instruments can routinely measure to an accuracy much better than 0.5%; however, in order to reach this potential, the solutions used in these techniques must be prepared to an accuracy three to ten times better (0.16% to 0.05%). Change in solvent density as temperature increases by 5º C.Solvent % DecreaseAcetone 0.758Acetic Acid 0.510Methanol 0.827Ethanol 0.825n-Propanol 0.503Methyl Ethyl Ketone 0.658Toluene 0.616Benzene 0.687Carbon Tetrachloride 0.401Chloroform 0.422Methylene Chloride 0.513Water 0.116Cyclohexane 0.706Dimethyl Sulfoxide 0.497TABLE 1Solution Preparation—Solvent MixingWhy prepare solutions gravimetrically rather than volumetrically? • Safety is improved because the pouring and spillage associated with the volumetric method is reduced dramatically or eliminated.• The gravimetric method is inherently more accurate than the volumetric method because the tempera-ture of the solvent can be ignored. The amount of solvent contained by a volumetric flask is a function of temperature—but the weight of the solvent is not affected by temperature. What are the costs of solvent mixing & solution preparation using the volumetric method vs the gravimetric method (PhasePrep II)?• The cost of purchasing, replacing and cleaning of volumetric glassware. With the PhasePrep II this is replaced by the cost of uncalibrated solvent containers.• The cost of wasted solvent. With the PhasePrep II, 135 ml or 653 ml of a solu-tion can be prepared as easily as one liter. Solvent waste is minimized.• The safety cost of handling solvents. The PhasePrep II is a closed system. The exposure to spilled solvents, broken glassware and harmful solvent vapors is reduced.• The cost of loosing laboratory integrity. This is the highest cost of all. What price can be put on mis-identifying a peak in a chromatogram because the solvent was not mixed accurately or a misla-beled solvent was used? The PhasePrep II prepares mixtures to an accuracy of a few hundreths of one percent or better—every time. A label is also printed to document the preparation. This minimizes the cost of re-works, non-conformance investigations and the costly delays that could result in not shipping finished product. Sample LabelMethod Selection ScreenMethod Editing ScreenSolution Preparation—Solvent Mixing