VAPRO 5520

VAPRO 5520 from Wescor, Inc. an ELITech Group Company

The most advanced, easy to use osmometer ever developed

Kent Thomas

370 West 1700 South

Logan, UT 84321

United States of America

No other vapor pressure osmometer has the credentials of Wescor's Vapro Vapor Pressure Osmometer. Since 1973 when Wescor introduced its first vapor pressure osmometer, the vapor pressure method has proven itself in thousands of laboratories and myriad applications. Our customers have rendered a clear verdict-vapor pressure osmometry is superior to all other methods:

"Vapor pressure measurement is the fastest and easiest method of determining osmolality, and the thermodynamic limitations of vapor pressure osmometry are least restrictive. For these reasons, vapor pressure osmometry is the method of choice for most fluids in biology and medicine in which water is the solvent."1

The fundamental advantages of vapor pressure osmometry are now embodied in the most intelligent osmometer ever developed. Wescor's Vapro Vapor Pressure Osmometer offers an intuitive approach that frees you from intensively "managing" an instrument.

Why Vapor Pressure?

The Vapro Vapor Pressure Osmometer method determines osmolality at room temperature with the sample in natural equilibrium. This precludes cryoscopic artifacts due to high viscosity, suspended particles or other conditions that can interfere with freezing point determinations, giving Vapro a much broader range of error free applications.
Easy Calibration

With the Vapro osmometer, say goodbye to frequent and intricate calibration procedures. Vapro is self-calibrating and exceptionally stable. Calibration is verified using osmolality standards. If recalibration is necessary, simply select the calibration option. Calibration is then performed and verified by the instrument.
Customer Support

Wescor osmometers have established an unrivaled record of reliability over all other osmometers. This is backed by Wescor's strong commitment to customer service. You will always find the help you need from our knowledgeable and friendly service staff.

How It Works

In most solutions, changes in concentration are accompanied by linear and proportional changes in the cardinal colligative properties of the solvent-vapor pressure, freezing point and boiling point. Measuring any of these properties provides an indirect indication of osmolality, but among them, only vapor pressure can be determined without a forced change in the sample's physical state.

In the Vapro osmometer, vapor pressure is determined thermometrically by a fine wire thermocouple suspended in a small vapor space above the specimen in a sealed sample chamber. During a measurement cycle, the thermocouple undergoes a series of microprocessor controlled temperature changes.