Advantages and disadvantages of buffer solution

Definition of the buffer: Buffer is a compound or mixtures of compounds that resist changes in pH by the addition of small amounts of acid or alkali by their presence in the solution.

A buffer solution is an aqueous solution that contains a weak base and its conjugate acid or a weak acid mixture and its conjugate base. It avoids the changes in pH or slight changes as applying small amounts of strong acid or base to it. Buffer solutions are widely used in a range of chemical applications as a way of maintaining pH at a nearly constant value. Several systems use buffering for pH regulation.

Advantages of buffer solution:

• The major advantage of a buffer is that it is keeps the pH stable and increase the solubility of the substance or formulation.
• Buffer solution plays a significant role in chromatography, as retention of ionizable molecules is extremely sensitive to the pH of the mobile phase in such cases the pH can be regulated by adding a buffer solution.
• The buffer solution can remain stable for several weeks if it is stored in the fridge.
• Different types of buffers such as acetate, ammonium, sodium, and phosphate, etc. are highly soluble in water.
• The pKa of a buffer solution is the same as being body fluids; hence it is used in the dissolution testing to determine the extent and rate of solution formation from a dosage form.
• It maintains the solubility of the therapeutic agent in the pharmaceutical product.
• Buffer solution improves the stability of products where the active agent is pH-dependent.
• It is non-toxic to cells and inhibits enzymatic reactions.
• By using the buffer solution the onset of action of dosage form increases.
• It is used to optimize biological activity.
• Since the pH of the buffer solution is precise, standard buffers i.e. pH 07.00, 04.00, and 09.20 are used to calibrate the analytical instruments (pH meter).

Disadvantages of buffer solution:

• The major disadvantage of the buffer solution is that it is an aqueous solution that can be contaminated with microorganisms and is not suitable for long-term storage, so you need to prepare a fresh buffer solution each time.
• To adjust the pH of the solution, it is necessary to know the pKa value of the component. 
• The drug dissolution may precipitate when the pH of the solution is not maintained properly.
• Some types of the buffer are precipitated and tend to react.
• Drug ingredients and some vitamins are dissolved only at a particular pH therefore, it is essential to maintain the correct pH of the solution.

Commonly asked questions about buffer solutions are as follows.

What are the types of buffer solutions?

There are two types of buffer solutions: acidic buffer solutions and alkaline buffers.

What is the range of pH scale?

The pH scale determines how acidic or basic a substance is in the range of 0.00 to 14.00 pH. A pH of 7.00 is neutral; a pH less than 7.00 is acidic and a pH greater than 7.00 is basic.

What are the applications of buffer solution in the pharmacy?

The buffer solutions are used in pharmaceutical industries for improving purity, increased stability, enhancing solubility, and optimizing the biological activity of the compounds or products.