Active substance: Amoxicillin
Abstract Background Child mortality is a major global health challenge, especially in regions of limited resources. To our knowledge, until now, peanut butter has not been used to formulate pharmaceuticals and its suitability as a matrix for antibiotics has not been tested.
We reasoned that the low water and high fat content of a peanut butter matrix would likely be beneficial to the stability of the pharmaceuticals it carried.
We tested each formulation at 50 mg amoxicillin per gram of matrix. Quantifying amoxicillin level in peanut butter matrix Peanut butter is a high-fat substance, and the amoxicillin in NutMox needed to be extracted from peanut butter before being measured.
Based on this known solubility, we developed an aqueous extraction procedure that extracted amoxicillin from peanut butter matrices through a series of water dilutions and extractions see Materials and methods.
Extracted samples were then analyzed by a colorimetric assay using hydroxylamine and ferric ammonium sulfate.
First, NutMox samples were extracted with water to recover amoxicillin. The aqueous extracts were then treated with hexane to remove the fatty contents. Subsequently aqueous extracts were filtered before being used for UPLC analysis.
Stability of amoxicillin in the peanut butter matrix Stability of the amoxicillin in the NutMox formulations was a key requirement for its preclinical development.
A standard stability test is typically conducted by storing the pharmaceutical for a period of several months to a year.
Due to the extended duration of the test, we first tested the stability of amoxicillin at elevated temperatures to assess the effect of the peanut butter matrix on amoxicillin.
Aliquots were collected from each sample at various time points and amoxicillin levels were determined by the hydroxylamine assay Figure 1.
Of the four formulations tested, the amoxicillin level in the aqueous suspension became undetectable after 1 h of exposure. In contrast, amoxicillin in capsules and in peanut butter matrices survived the heat treatment to various extents.
Figure 1. The amoxicillin level was determined in each sample. The level of amoxicillin after incubation is shown as a percentage of the initial level.
Results are the average of experiments and error bars represent standard deviations.