1X PBS Recipe Calculator

Phosphate-buffered saline (PBS) is a widely used buffer solution in biological research, providing an isotonic environment suitable for cell culture, biochemical assays, and molecular biology applications. The 1X PBS solution consists of sodium chloride (NaCl), potassium chloride (KCl), disodium hydrogen phosphate (Na₂HPO₄), and potassium dihydrogen phosphate (KH₂PO₄), maintaining a physiological pH of approximately 7.4.

Alfa Chemistry offers the 1X PBS recipe calculator to simplify buffer preparation and ensure accuracy and reproducibility in biological studies.

Desired Volume

mL

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Sodium chloride (NaCl)

g

Potassium chloride (KCl)

g

Disodium hydrogen phosphate (Na₂HPO₄)

g

Monopotassium phosphate (KH₂PO₄)

g

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If you are using a 10X PBS configure a 1X PBS solution:

Desired Volume

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mL of 10X PBS Stock Solution

mL of deionized water

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Composition of 1X PBS Solution

The standard 1X PBS solution contains the following ionic concentrations:

Component	Concentration (mM)
NaCl (ACM7647145)	137
KCl (ACM7447407)	2.7
Na2HPO4 (ACM7558794)	10
KH2PO4 (ACM7778770-3)	1.8

These concentrations replicate physiological conditions, making PBS ideal for maintaining osmolarity and pH stability in biological experiments.

Preparation Method for 1L of 1X PBS

To prepare 1 liter (L) of 1X PBS solution from individual reagents, follow these steps:

1. Prepare a clean container: Use a glass beaker or plastic bottle with a capacity of at least 1L.
2. Add 800 mL of distilled water.
3. Dissolve the following components in water:
   • 8.0 g NaCl
   • 200 mg KCl
   • 1.44 g Na₂HPO₄
   • 240 mg KH₂PO₄
4. Adjust pH: The solution should be adjusted to pH 7.4 using NaOH or HCl if necessary.
5. Dilute to final volume: Add distilled water until the total volume reaches 1 L.
6. Sterilization (optional): The solution can be sterilized via autoclaving or filtration (0.22 μm filter) if required for sensitive applications.

Preparation from 10X PBS Stock Solution

A 10X PBS stock solution can be used to simplify the preparation process. To prepare 1L of 1X PBS from 10X stock:

1. Measure 100 mL of 10X PBS.
2. Dilute with 900 mL of distilled water.
3. Mix thoroughly to ensure homogeneity.
4. Confirm pH (should be ~7.4).

This method ensures rapid preparation and consistency, particularly in high-throughput laboratory settings.

Importance of PBS in Biological Research

PBS is crucial for various biological applications, including:

• Cell culture: Maintains osmotic balance and prevents cell damage.
• Western blotting & ELISA: Used as a washing buffer to remove unbound antibodies.
• Molecular biology: Supports enzymatic reactions and sample dilution.
• Tissue engineering: Provides physiological pH conditions for tissue and organ culture.