How to prepare a Saline Solution?

How to prepare a Saline Solution
How to prepare a Saline Solution

The word saline solution refers to a salt solution that may be made at home with widely available ingredients. The solution can be used to disinfect, sterilize, or do laboratory work. This recipe makes a normal salt solution, which is the same concentration as, or isotonic to, bodily fluids. A saline solution’s salt hinders bacterial growth while washing away pollutants. Because the salt content is comparable to that of the body, it results in less tissue damage than pure water.

The saline solution can be used to flush the passageways of the nose and sinus to help wipe out mucus, germs, and viruses. Nasal “washing,” like handwashing, helps minimize the level of virus, germs, allergies, and other substances that the immune system has to battle.

Normal Saline Solution (NSS) is often used in different laboratory operations such as the production of Red Cell Suspension for crossmatch, preparing of dilute solutions of Reagents, stool examinations, the production of dilute solutions in serological analyses, diagnostic tests, and so on.

How to Calculate Normal Saline Solution

Normal saline solution is simply 0.85% Sodium chloride (NaCl) solution, which could be made in the laboratory by dissolving the estimated amount of Sodium chloride crystals in the appropriate quantity of Distilled water.

Because the distilled water to NaCl ratio is 0.85g:100 ml, you may utilize the ratio to create large quantities of the solution.

To calculate the mass of NaCl that is required, use the formula:

  • NaCl mass = (Quantity required * 0.85)/100
  • To create 1000ml of normal saline, for example:
  • NaCl mass = (1000*0.85)/100
  • NaCl mass = 8.5g

Reagents Required

  • Distilled Water
  • Sodium Chloride (NaCl) Solution

Required Apparatus

  • Funnel
  • Volumetric Flask/Beaker
  • Stirrer
  • Weighing Scale

Procedure of Preparing Normal Saline Solution

  • Weigh 8.5 grams of sodium chloride (NaCl) using a weighing scale.
  • Take 500 ml of distilled water then place it in the volumetric flask or a Beaker. Then, add 8.5 gram of NaCl to the mixture.
  • If you’re mixing the solution in a beaker, use a stirring tool to whisk the ingredients together while slowly swirling the flask.
  • Add distilled water to the solultion after NaCl is fully dissolved, subsequently adjusting the amount to 1 liter.
  • Place an airtight cork in the volumetric flask’s opening and give it a slight shaking to homogenize the solution. If you’re using a beaker, thoroughly swirl the solution using a stirrer.
  • The created normal saline solution should now undergo a 15-minute sterilization process at 121 °C and 15 psi pressure. When the solution is sterilized, it becomes laboratory-grade normal saline solution, which may be used for both pathological and microbiological analysis.

Procedure for preparing 0.9% Normal Saline

  • Weigh 0.9g of NaCl on the balance.
  • Pour it into the volumetric flask.
  • Fill the flask halfway with distilled water and stir to dissolve.
  • Fill to the 100ml mark with distilled water and stir to dissolve.
  • Fit the flask with an airtight cork.
  • Place the preparation in an autoclave and sterilize for 15 minutes at 15psi and 121oC.
  • Place the solution in a reagent bottle and label it ‘Normal saline.’

Applications of Normal Saline Solution In Lab

  • To preparing red cell suspension for crossmatch for blood transfusion.
  • For diluting reagents.
  • For examining stools with moist preparation.
  • To make dilutions in serological tests.
  • For maintaining cell integrity and vitality.
  • For assisting with moist preparations for microscopic inspection.

Other Uses of Normal Saline Solution

  • It is used by doctors to treat hypovolemia or shock caused by dehydration, minor sodium depletion, and metabolic alkalosis in the context of fluid loss in children and adults.
  • Used for cleaning contact lenses and as eye drops.
  • Administration of residual blood from the administration kit (up to 40ml) and flashing the line for later use. Normal saline is the only solution that is compatible with blood and its constituents. Other solutions can produce coagulation and hemolysis in the blood.
  • Nasal irrigation and rinse.
  • Irrigation and rinsing of the bladder tubes.
  • For washing and cleaning the wounds.

Frequently Asked Questions (FAQ)

How do you make 500 mL of normal saline?

Dissolve 4.5 grams of NaCl in 500 mL of sterile water to make 500 mL of normal saline.

How do you make 1 liter of normal saline?

1 liter of normal saline is made by dissolving 9 grams of NaCl in 1 liter of sterile water.

How do you make 0.9% NaCl 500ml?

To prepare 500 mL of 0.9% NaCl (normal saline), dissolve 4.5 grams of NaCl in 500 mL of sterile water.

Video on Preparation of Saline Solution

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About Author

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Jyoti Bashyal

Jyoti Bashyal, a graduate of the Central Department of Chemistry, is an avid explorer of the molecular realm. Fueled by her fascination with chemical reactions and natural compounds, she navigates her field's complexities with precision and passion. Outside the lab, Jyoti is dedicated to making science accessible to all. She aspires to deepen audiences' understanding of the wonders of various scientific subjects and their impact on the world by sharing them with a wide range of readers through her writing.

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