Alternatives to Volumetric Solution and Sample Preparation

The demand for greater accuracy from analytical instruments has prompted the automation of sample and solution preparation based on the much more accurate ‘solvent weight’ to ‘sample weight’ basis - the gravimetric method.

The gravimetric method is inherently more accurate than the volumetric method because the temperature 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. 

The integrity of HPLC analysis is dramatically affected by the composition of the solutions used; a slight error can result in misidentification of sample components. This can have very serious consequences for a pharmaceutical company. Design Scientific's instruments excel in preparing routine solutions gravimetrically. Benefits of automating the mixing of solvents for HPLC are combination of solvent savings, labor savings and automatic documentation.

SoluPrep™ is appropriate for any laboratory that prepares solutions, automatically preparing samples with exceptional accuracy for LC, GC, standards and spectroscopy. Sample sizes range 5mL to 250mL. SoluPrep’s highly sensitive solvent weighing precision, 0.0001g, and Design Scientific’s proprietary software result in high quality samples every time. The solvent delivery rate is 100 mL/minute. SoluPrep also automatically documents every sample.

PhasePrep™ functions in the same easy to use manner as the SoluPrep. PhasePrep is designed to prepare large batch routine solutions for HPLC mobile phases, titrations, extractions and internal standards. At 500mL/minute, PhasePrep quickly and accurately prepares solutions ranging from 50mL to up to 8L. 

SoluPrep and PhasePrep eliminate costly volumetric glass-ware, user-to-user variation and inaccuracies related to temperature. A label is also printed to document the preparation. This minimises the cost of re-works, non-conformance investigations and the costly delays that could result in not shipping finished product. Both instruments offer a full GMP Validation Package.

Costs of using the Volumetric Method:

• Volumetric Cost: volumetric glassware. Gravimetric systems can use any vessel.
• Volumetric Cost: wasted solvent. With the gravimetric method, any volume of a solution can be prepared as easily as one liter.
• Volumetric Cost: safety. With a gravimetric closed system, exposure to spilled solvents, broken glassware and harmful solvent vapors is reduced. 
• Volumetric Cost: losing laboratory integrity; misidentifying a peak in a chromatogram because the solvent was not mixed accurately. Automating preparations with the gravimetric method provides consistently accurate results.