Quantification of monolaurin synthetically produced from Lauric acid and glycerin esterification: novel method via 1H NMR
Year: 2025
Type: article
Abstract: Monolaurin (ML) is a monoglyceride naturally present in human breast milk, which exhibits beneficial results against pathogenic microorganisms, including various bacteria and viruses. Thus, given the importance of ML to prevent several diseases in newborn children, it is necessary to investigate efficient routes to produce it synthetically and to develop novel analytical methods to characterize it. This work focuses on the development of a method based on the quantitative 1 H Nuclear Magnetic Resonance Spectroscopy (q 1 H NMR), to approach the selectivity to ML produced through the acid-catalyzed esterification of LA with GL. Interestingly, the developed method is also capable to quantify the amount of dilaurin (DL) and eventually trilaurin (TL) coproduced in the synthesis of ML. From three replicated LA-GL esterification experiments carried out in batch over a commercial catalyst at the conditions: 3 mol/mol GL to LA, 150 °C, 5 g catalyst/100 g LA and 60 min, the q 1 H NMR results show that selectivity to ML, DL and TL amounts to 53.28 ± 2.05, 43.39 ± 2.0 and 1.33 ± 0.14 wt%, respectively, with variation coefficients below 10 %. These values are very close and exhibit a similar precision level compared to those obtained via chromatography coupled to mass spectrometry (GC–MS), i.e., 55.89 ± 1.60, 41.80 ± 1.45 and 1.09 ± 0.10 wt%, respectively. Moreover, the detection limit of the proposed q1H NMR method was found to be 0.4 mg/mL for ML. It is demonstrated that the q 1 H NMR is a nondestructive, low-cost, simple, efficient, high precision and reproducible technique for determining the selectivity to ML, DL and/or TL in the esterification of LA with GL, the precision of the reported method is comparable to that displayed by more sophisticated techniques such as GC–MS.
Source: Microchemical Journal
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,000
Awards: G5182855907, G7702303356
OpenAlex ID: W4414797413
