Determination of 5-hydroxymethylfurfural (5-HMF) in Expired Pharmaceutical Syrups by Using HPLC-DAD Method

The Maillard reaction product 5-hydroxymethylfurfural (5-HMF) is formed under acidic conditions by the dehydration of sugars in carbohydrate-based food and pharmaceutical products during heating and storage. As pharmaceutical syrup formulations contain sugar and are stored under room temperature, they provide favorable conditions for the formation of 5-HMF. The long-term storage of syrup bottles after their cap has been opened and the unintentional use of expired syrups can lead to the formation of undesirable products such as 5-HMF in medications. Although legal limits have been established for 5-HMF content in pharmaceutical preparations, these levels may exceed those limits in hot climates or under inappropriate storage conditions. The present study detects and measures 5-HMF levels in expired pharmaceutical syrups through the HPLC-DAD (High Performance Liquid Chromatography with Diode Array Detection) method, and investigates the effects on 5-HMF levels of the 72-hour storage of syrups at temperatures of 40˚C. The 5-HMF level in syrups stored at room temperature varied between 1.34 μg/mL to 15.63 μg/mL, while in syrups stored at higher temperatures, the levels ranged from 2.24 μg/mL to 18.24 μg/mL. This indicated that 5-HMF content in syrups stored at 40 ˚C was higher than those measured in syrups stored at room temperature, although the increase was not found to be statistically significant (p>0.05). In addition to measuring the amount of 5-HMF in pharmaceutical syrups, this study also examined the changes in the levels of this dehydration product in syrup formulations under hot climates and according to storage conditions.