How pH and Temperature Influence Ampicillin Degradation: A Zone of Inhibition Study

Mancen Gao; Xinyang Guo; Yulin Jiang

doi:10.6911/WSRJ.202512_11(12).0001

Authors

Mancen Gao
Xinyang Guo
Yulin Jiang

DOI:

https://doi.org/10.6911/WSRJ.202512_11(12).0001

Keywords:

Ampicillin, Antibiotic Stability, Zone of Inhibition, Temperature Degradation, pH Denaturation

Abstract

Antibiotics such as ampicillin (C₁₆H₁₉N₃O₄S) are essential for treating bacterial infections, and their efficacy depends on environmental conditions like pH and temperature. This study examined how ampicillin’s antibacterial activity—measured via zone of inhibition assays—is affected by different pH levels (5.5, 7.2, 8.5) and temperatures (4°C, 25°C, 50°C, 80°C). Results showed that neutral pH (7.2) and lower temperatures (4–25°C) best preserved ampicillin’s activity, while alkaline conditions (pH 8.5) and high temperatures (≥50°C) caused significant degradation. These findings highlight the importance of proper storage and handling to maintain ampicillin’s clinical effectiveness.

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