This product measures dew point by a method which volatilizes, condenses, and revolatilizes a portion of the solvent, and has been demonstiated to provide seriously erroneous data, particulariy in the presence of volatiles, according to lab. Vapor pressure osmometry is a dynamic method of determining the vapor pressure of solutions. Wescor 5500 vapor pressure osmometer in stock, we buy. With the product code you gain access to the technical documents of this product. Alternative methods of estimating the water potential at turgor loss. Our customers have rendered a clear verdictvapor pressure osmometry is superior to all other methods.
Discovery diagnostics, canadian distriubor of wescors vapro vapor pressure osmometer. Vapor pressure and freezing point osmolality measurements applied to a volatile screen. It used to be that freezing point osmometers were priced 30% or more over their vapor pressure cousins. An osmometer is a device for measuring the osmotic strength of a solution, colloid, or compound there are several different techniques employed in osmometry. The osmometer shall be capable of routine osmolality determinations on sample volumes of 10 microliters and shall perform the meas urement automatically once the chamber is sealed. The osmometer has a small chamber to which is sealed a thermocouple hygrometer.
A vapor pressure osmometer was used to measure the. The vapor pressure osmometer k7000 has been designed to exactly measure the total. A thermocouple measures temperature by the voltage between two. The osmometer shall be a elitech model 5600 or equivalent and shall operate on the vapor pressure depression principle. Simple to use just lower the head to run the test fast 90 second tests highly reliable, with the fewest moving parts available narrow profile design uses only uses 5 of your bench space 0 to 2000 mosmkg range. The wescor vapro model 5600 vapor pressure osmometer, can be used to. Multiple c52 chambers can be connected to the cr7 datalogger to function as an automated multichannel osmometer as an osmometer, can do rapid, accurate sampling without freezing 10 microliter samples. Osmometer vapro 5600 elitech, for laboratory, rs 767000 unit. K7000 vapor pressure osmometer dampfdruckosmometer knauer. It is a modified isopiestic technique that involves measuring the steadystate temperature difference that develops between a drop of solution and a drop of pure solvent commutually exposed to an atmosphere saturated with.
Vapor phase osmometry vpo, also known as vaporpressure osmometry, is an experimental technique for the determination of a polymers number average molecular weight, m n. Osmometer an instrument that can find the osmotic strength of a solution or colloid using data from a semipermeable membrane, freezing point depression or vapor pressure. This item was in working condition at the time it was removed from the lab. Vapro vapor pressure osmometer brochure elitechgroup. The model 5520 is an excellent instrument to determine osmolality at room temperature with the sample in natural equilibrium. Vapro is the undisputed leader in research osmometry. The osmolality of the patient is determined by freezing point method freezing.
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 errorfree applications. Osmometry a laboratory technique to find the molecular weight of an unknown compound by determining the osmotic strength of a solution. The wescor 5500 vapor pressure osmometer brings unprecedented simplicity, convenience, and accuracy to the routine determination of osmolality to help meet the demands placed on todays clinical laboratory. This unit is the method of choice for most fluids in biology and medicine in which water is the solvent. The fundamental advantages of vapor pressure osmometry are now. A method is described for determining brain osmolality with a vapor pressure osmometer. An instrument for measuring osmolality by freezing point depression or vapor pressure elevation techniques. Thank you for purchasing the vapro vapor pressure osmometer. Measurement of root and leaf osmotic potential using the. Use of a vapor pressure osmometer to measure brain. Osmometer definition of osmometer by medical dictionary. All of these methods were based on colligative properties such as freezing point depression cryoscopy gross et al.
There are a variety of osmometers, including vapor pressure depression osmometers, membrane osmometers, and freezing point depression osmometers. Use of a vapor pressure osmometer to measure brain osmolality. Specifications vapro vapor pressure osmometer model 5600 manufactured by. The vapor pressure osmometer k7000 is best suited for. Readjust the thermistors with careful manual bending until a distance of. Since then, the vapor pressure method has proven itself in thousands of laboratories and myriad applications. This technique can be used for polymers with a molecular weight of up to 20,000. Vaporpressure osmometer article about vaporpressure. The fundamental advantages of vapor pressure osmometry are now embodied in the most intelligent osmometer ever. Vapor phase osmometry university of texas at austin.
The osmometer shall be capable of routine osmolality determinations on sample volumes of 10 microliters and shall perform the measurement automatically once the chamber is sealed. The osmometer shall be a wescor model 5520 or equivalent and shall operate on. Direct measurements vapourpressure osmometer and dewpoint. Wescor elitechgroup vapro 5600 vapor pressure osmometer. Find out information about vaporpressure osmometer. The general agreement found for molecular weights determined under a variety of conditions, leads to the conclusion that values as high as 100,000 daltons can be determined by at least one type of vapor pressure osmometer when it is calibrated with a material of 200 daltons. Vapor pressure and freezing point are among the colligative. While mem brane osmometry mo provides a potentially unlimited. For these reasons, vapor pressure osmometry is the method of choice for most fluids in biology and medicine in which water is the solvent. Vapor pressure osmometers determine the concentration of osmotically active particles that reduce the vapor pressure of a solution membrane osmometers measure the osmotic pressure of a solution. An apparatus for measuring the acuteness of the sense of smell. Vapro vapor pressure osmometer elitechgroup benelux.
Osmometer measurements were taken with a vapour pressure osmometer vapro 5600, wescor, logan ut, usa. It works by taking advantage of the decrease in vapor pressure that occurs when solutes are added to pure solvent. Please note that this unit has not been professionally tested, and is being sold as is. For sale from wescor vapor pressure osmometer 5500.
The fundamental advantages of vapro have been enhanced with. Fast membrane osmometer as alternative to freezing point. Vapor pressure and freezing point osmolality measurements. The vapro vapor pressure osmometer, can be used to determine the osmolality in any type of sample. Osmometers vapor pressure osmometer k7000 the vapor pressure osmometer k7000 from knauer is an advanced instrument from one of the pioneers in the field of osmometry with 50 years experience. Used in a variety of settings, clinical osmometers measure these levels by deploying one of two methods. Used wecor vapro model 5600 vapor pressure osmometer. The wescore model 5500 vapor pressure osmometer the wescor vapor pressure osmometer employs the most uptodate method of osmolality determination.
The required sample volume is only two to ten microliters ten microliters for routine operation and because the technique is both fast and readily learned. Journal of neuroscience methods, 3 1980 25 elseviernorthholland biomedical press 21 use of a vapor pressure osmometer to measure brain osmolality patricia a. The vapro osmometer is an advanced electronic adaptation of the hygrometric method of vapor pressure determination. The new vapro can be used to determine the osmolality in any type of sample. Osmometer definition of osmometer by the free dictionary. The determination of m n operates on the principle that the vapor pressure of a solution is lower than that of the pure solvent at the same temperature and pressure magnitude of the vapor pressure decrease is directly proportional to the molar concentration of solute does not directly measure vapor pressure but measures change in. The wescor vapro machines are the only game in town when it comes to vapor pressure osmometers due to patent issues. Osmometers semimicro osmometer k7400 typical applications for the semimicro osmometer k7400 range from routine testing of physiological fluids such as blood serum and urine in clinics up to quality control of food products like milk or isotonic soft drinks.
This is a report of a rapid and precise screening procedure, developed for the determination of ethanol in serum using osmolality measurements. Information is presented in a stepbystep format to demonstrate the. Measuring relative vapor pressure of organic solvent solutions alcohol, acetone, carbon tetrachloride, toluene, benzine, etc. Tornheim department of anatomy, university of cincinnati, college of medicine, 231 bethesda avenue, cincinnati, ohio 45267 u. The osmometer shall consume no more than 40 watts of electrical power and shall weigh less than 7 kg. A vapor pressure osmometer was used to measure the osmolarity of the samples from mcb 32 at university of california, berkeley. This let the wescor machines take over significant market share. The vapro osmometer requires a sample volume of only 10 microliters. The vapor pressure method determines osmolality at room temperature with the sample in natural equilibrium. Vaporpressure thermometer definition is a thermometer in which the variable saturated vapor pressure of a volatile liquid is used as a measure of the temperature and which thus has the advantage over some other types of thermometers of being free from errors due to. Clifton nanolitre osmometer clifton technical physics osmometer. This instrument is in likenew condition and is priced at less than half the cost of a new one. Osmometers measure the osmotic strength of a sample. This instrument measures dew point temperature depression of a solution in.
The sensitive thermocouple and sophisticated electronics provide the means to measure the dew point temperature depression of a specimen with resolution to 0. The wescor osmometer measures the vapor pressure relative humidity by measuring the dew point temperature at which water condensate is in equilibrium with the water vapor in the overlying atmosphere. The vapor pressure method is suitable for the determination of the average molecular weight of polymers which are soluble in a variety of different organic solvents and for the determination of osmolality of aqueous solutions. The osmometer shall have an automated thermocouple cleaning cycle and not require any routine maintenance. Wescor 5500 vapor pressure osmometer alternate names. Calibration of vapor pressure osmometers for molecular. Vaporpressure thermometer definition of vaporpressure. The vaporpressure osmometer vpo is used to measure osmotic potential in plant water relations. Elitechgroup offers the vapro vapor pressure osmometer. Extended range with a switch on the back holdrun which. It stands out for its high performance, data quality, and reliability. Wescor vapro vapor pressure osmometer thermal couple.