Benefits of Osmotic Pressure in General

Osmosis is defined as the net flow or movement of solvent molecules through a semipermeable membrane that cannot be passed by dissolved molecules. If the buffer solution consists of dissolved molecules and the solvent is placed on one side of the membrane and the pure solvent is placed on the other side, there is a clean flow of the solvent to the side of the membrane solution. Osmotic pressure is an important factor affecting cells.

Besides relating to the body of living things, the working principle of osmosis pressure can also be used as a basis for filtering (” reverse osmosis “), a process commonly used in water purification. The water to be purified is placed in a chamber and placed under an amount of pressure greater than the osmotic pressure exerted by the water and the solutes therein.

table of contents

  • Osmotic Pressure
    • Benefits of Osmotic Pressure
      • Physiological osmotic pressure
      • Determination of molecular weight 
      • Seawater osmosis can generate electricity 
      • Water transportation in plants 
      • Dialysis Process 
      • For food preservation 
      • Sea Water Purification or Desalination
      • Purification of wastewater 
      • The working principle of infusion 
      • The working principle of the body’s ion replacement drink 
    • Spread this:
    • Related Posts:

Osmotic Pressure

Osmosis is the diffusion of certain water through a semi-permeable membrane. So in the case of osmosis, solutes cannot move because they cannot pass through the membrane. However, water can move, and that – across the membrane to areas with higher solute concentrations.

This can cause the total volume of water on each side of the membrane to change: the membrane side with more solutes may end up with more water. This can cause problems for the cell, such as exploding (if too much water moves into the cell), or becoming dehydrated (if too much water moves out).

This is a very important factor in biology because the intracellular environment is different from the extracellular environment. If the extracellular environment changes, it can cause water to flow into our cells.

Some organisms, such as plants that use osmotic pressure to move water, have taken advantage of this principle. But it can also threaten the health of cells and organisms when there is too much or too little water in the extracellular environment compared to the inside of cells.

Definition of Osmotic Pressure

Osmotic pressure is the minimum pressure that needs to be applied to the solution to prevent the influx of pure solvent from entering the semipermeable membrane. This is also defined as a measure of the tendency of solutions to take in pure solvents by osmosis.

Osmotic potential pressure is the maximum osmotic pressure that can develop in solution if separated from pure solvents by a semipermeable membrane. Osmosis occurs when two solutions, which contain different concentrations of solutes, are separated by a permeable selective membrane.

Solvent molecules pass specifically through the membrane from a low concentration solution to a solution with a higher solute concentration. The transfer of solvent molecules will continue until equilibrium is reached.

Understanding Osmotic Pressure According to Experts

The definition of osmotic pressure according to experts, among others:

Biology Dictionary

Osmotic pressure can be considered as the pressure needed to stop water from diffusing through osmotic barriers. In other words, this refers to how hard the water will “push” over the barrier to diffuse to the other side.

Osmotic pressure is determined by the concentration of solutes – water will “try harder” to diffuse to areas with high solute concentrations, such as salt, rather than to areas with low concentrations.

In reality, of course, osmotic pressure is not a “desire” of water to move, but rather an extension of the natural law that all matter will be distributed randomly over time.

When the concentration of different substances in two areas and areas have contact with each other, random movements of particles will cause the substance to diffuse until the solution is uniform throughout the area.

Lumen Learning

Osmotic pressure is the pressure that needs to be applied to prevent the flow of water into the semipermeable membrane. Osmotic pressure can also be explained as the pressure needed to stop osmosis.

One way to stop osmosis is to increase the hydrostatic pressure on the membrane solution side; this ultimately squeezes the solvent molecule closer together, increasing the “escape tendency.”

The runaway tendency of the solution can be increased until finally it is the same as the molecule in pure solvents; at this point, osmosis will stop. Osmotic pressure is the pressure needed to achieve osmotic balance.

Benefits of Osmotic Pressure

Osmotic pressure has a variety of benefits, including:

Physiological osmotic pressure

Osmotic pressure plays an important role in physiological processes in humans, including:

  1. Absorption from the digestive tract, also the exchange of fluids in various compartments of the body follows the principle of osmosis.
  2. Osmotic pressure of plasma proteins regulates water flowing from protein-free intestinal fluid into blood vessels.
  3. Living red blood cells, if suspended in 0.92% NaCl solution, do not get or lose water. Briefly, intracellular fluid of red blood cells is isotonic with red blood cell membranes in 0.92% NaCl solution.

Determination of molecular weight 

Because all the colligative properties of the solution depend on the concentration of the solvent, its measurement can serve as an easy experimental tool to determine the concentration, and thus the molecular weight of the solute.

Osmotic pressure is very useful in this case, because a small amount of solute will produce a far greater change in this amount than at boiling point, freezing point, or vapor pressure. even 10-6 molar solutions will have measurable osmotic pressure.

Determination of molecular weight is very often done on proteins or polymers with other high molecular weight. These substances, because of their large molecular size, tend to be only slightly soluble in most solvents, so measuring osmotic pressure is often the only practical way to determine the molecular weight.

Seawater osmosis can generate electricity 

The working principle of osmosis pressure can also be used to produce electricity sourced from sea water. This process begins with feeding fresh water and seawater to the power plant. Sea water and fresh water will be filtered first to remove impurities.   

Furthermore, freshwater and sea water undergo different treatments, fresh water will be directly inserted into the membrane module, while sea water will be given additional pressure before entering the membrane module. In the membrane module there will be an osmosis event which causes 80-90% of fresh water to move through the membrane to pressurized sea water. 

After exiting the membrane module the volumetric flow rate of high pressure water will increase will flow towards the turbine. But not all of this sea water flow to the turbine but about 2/3 of the part will be fed to the pressure exchanger to apply pressure to the new sea water feed. The remaining water that is not fed into the pressure exchanger will flow through the turbine and drive the turbine to produce electricity.

Water transportation in plants 

Osmotic flow plays an important role in the transport of water from its source on the ground to its release by transpiration from leaves, aided by the strength of hydrogen bonds between water molecules.

Water enters the roots through osmosis, driven by low water concentrations in the roots which are managed by active transport [non-osmotic] ​​ionic nutrients from the soil and by the supply of photosynthetic sugars in the leaves.  

This produces a certain amount of root pressure which sends water molecules on their way through the trunk or stem veins. But the maximum root pressure that has been measured can push water only about 20 meters, while the tallest trees exceed 100 meters.

Root pressure can be the only driver of water transportation in short plants, or even in tall plants such as trees with no leaves. But when higher plants actively carry out transpiration (loss of water to the atmosphere), osmosis gets a boost from what physiologists call the tension cohesion or transpirational pull 

Because each H2O molecule emerges from a hole in the leaf, it pulls along the molecular chain underneath. So hydrogen bonds are no less important than osmosis in the whole process of water transportation.

Dialysis Process 

The principle of osmotic pressure can be applied in the medical field, namely in the process of dialysis or also known as dialysis. In the medical field, dialysis is very important for patients with kidney failure caused by kidney dysfunction so that it cannot function properly for blood filtration.

Dialysis technology allows blood filtration to be carried out outside the kidneys using a machine. The workings of this machine are the blood from the body will be inserted into the machine and will go through a semipermeable membrane.

Through these membranes, impurities in the blood can be separated through the dialysis membrane to separate from the blood so that you will get blood that is washed free from impurities.

For food preservation 

The working principle of osmotic pressure can be used in the food industry, namely for food preservation processes. This can be done by utilizing crenation in cells where to preserve food, the food industry usually uses sugar in large quantities to produce high concentration solutions.

With a solution that is highly concentrated or hypertonic, then when there are bacteria that come can not survive long because the water in the bacterial cell will experience osmosis out of the cell wall to the sugar solution with high concentrations.

The result is that the cells in the bacteria undergo a crenation event that results in the cell shrinking so that it loses its function and makes the bacteria die. The two substances most commonly used to create a hypertonic environment for microorganisms and prevent them from growing are salt and sugar.

  • Salt for preserving meat

Table salt (sodium chloride) is the main ingredient used in smoking meat. Removing water and adding salt to meat creates an environment that is rich in solutes where osmotic pressure attracts water from microorganisms, thus slowing its growth. Doing this requires a salt concentration of almost 20%.

  • Sugar for fruit preservation 

Sugar is used to preserve fruits, both in syrup with fruits such as apples, pears, peaches, apricots, plums or in the form of crystals where the preserved material is cooked in sugar to the point of crystallization and the resulting product is then stored dry.

The purpose of sugar is to create an environment that is not friendly to microbial life and prevent food spoilage. From time to time, sugar has also been used for non-food preservation.

For example, honey was used as part of the mummification process in some ancient Egyptian rites. However, the growth of fungus and fungus is not suppressed as efficiently as bacterial growth.

Sea Water Purification or Desalination

So that sea water can be used and consumed, it is necessary to purify water from dissolved substances that exist in sea water. This can be done by applying the working principle of osmotic pressure, which is by giving a pressure greater than the osmotic pressure of sea water so that water as a solvent will pass through a semipermeable membrane, leaving solutes in seawater that cannot pass through the membrane.

The process is referred to as reverse osmosis where the solvent in high concentration conditions will pass through a semipermeable membrane to a low concentration. But if this process is carried out without using great pressure then the opposite will occur, namely pure water will actually enter sea water.

Purification of wastewater 

Not only to purify seawater, the working principle of osmotic pressure can also be used as a waste water purification to remove hazardous substances before being discharged into the environment, namely through the application of reverse osmosis (RO) or reverse osmosis. The same is true when purifying sea water.

Reverse Osmosis applies pressure greater than the osmotic pressure (between 2-10 MPa) into the concentrate solution, thereby causing the solution to flow from the semipermeable membrane concentrate side to the dilute side .

RO has the ability to get rid of total dissolved inorganic solid 95-99.5% and dissolved organic solid 95-97%. The technology has been used to remove radionuclides from low-level liquid waste such as steam from nuclear power plants.

The working principle of infusion 

The working principle of infusion basically applies osmotic pressure. The principle of osmotic pressure in the use of infusion is an example of the application of the nature of colligative solutions in the health field. The inventor of the principle of osmotic pressure as one of the colligative properties of solutions is Jacobus Henricus van’t Hoff.

He was a Nobel Prize winner in 1901 for his research on kinetic chemistry about the meaning of chemical equilibrium , osmotic pressure, and crystallography. His research regarding osmotic pressure shows that the osmotic pressure of a solution is proportional to the concentration and temperature of the solution.

The working principle of the body’s ion replacement drink 

The principle of osmotic pressure is not only used in intravenous fluids, but body ion replacement drinks that are now rife in the community also use this principle as the basis for its manufacture.

Well, that was a complete explanation and review to all readers related to the benefits of osmotic pressure in general for human life. Hopefully through this material can provide insight and increase knowledge for all readers. Thanks,


Leave a Comment