Question

Which of the following is responsible for bridging in tablet coating?

• A. \( \text{Rapid drying of coating solution} \)
• B. \( \text{Over spraying of coating solution} \)
• C. \( \text{High moisture content of air} \)
• D. \( \text{Improper plasticizer} \)

Hint:

Imagine paint drying too fast over a groove – it forms a film across the top instead of flowing into it. Rapid drying of coating solution does something similar on tablets.

Answer 1

The Correct Option is A

Bridging in tablet coating refers to the filling or obliteration of the score line or debossed letters on a tablet surface by the coating material. Rapid drying of the coating solution is a primary cause of bridging. When the coating solution dries too quickly, it can solidify across the indentations before it has a chance to flow and uniformly cover the features, leading to a film that bridges over the score line or lettering. Improper plasticizer levels can affect the flexibility of the coating film, potentially contributing to edge chipping or cracking rather than bridging. Over spraying might lead to uneven coating or lamination. High moisture content of air can affect the drying rate but is less directly associated with bridging compared to the drying rate of the coating solution itself.