Determining the osmotic pressure (freezing point) of human tear by freezing point drop method (CAT#: STEM-PPA-0171-LJX)

Freezing point drop method is a commonly used method to measure the osmotic pressure (freezing point) of organisms. The method uses the Raoult freezing point principle, that is, any solution, if the total number of solute particles dissolved per unit volume is the same, the value that causes the freezing point of the solution to drop is the same.

For determining the freezing point and osmotic pressure of biological fluid

1. Measure the freezing point of pure water
2. Load the sample solution into the osmometer, so that the water in the sample begins to freeze, and record the temperature drop of the sample
3. When the temperature drops to a certain value, all the water in the sample freezes to form ice crystals. At this time, the sample temperature stops falling and the temperature value is recorded, which is the sample freezing point
4. The osmotic pressure of the sample can be calculated by establishing a standard curve

• Sample Type:
Human tear

1. During the experiment, strictly avoid the contact between the sample and the air to prevent the sample from losing water or absorbing water, which will affect the experimental results.
2. At the same time, the pH value, temperature, stirring time and other factors of the sample will also affect the experimental results and need to be controlled.