title: Analysis of free nucleotide monophosphates in human milk and effect of pasteurisation or high-pressure processing on their contents by capillary electrophoresis coupled to mass spectrometry.
abstract: A simple, efficient and green analytical method for the determination of free nucleotide monophosphates in human milk is proposed. It involves centrifugal ultrafiltration (CUF) as sample treatment and capillary electrophoresis-electrospray mass spectrometry (CE-ESI-MS) for separation and simultaneous quantification. The optimised method, applied to the analysis of human milk samples, included their dilution (1:5) with water followed by CUF treatment. No matrix effects were found. The method provided limits of detection between 0.08 and 0.13 μg mL(-1) and limits of quantification between 0.26 and 0.43 μg mL(-1). The intralaboratory repeatability and reproducibility afforded relative standard deviation values lower than 10%. The method was applied to the study of the effects of Holder pasteurisation and high-pressure processing on the nucleotide contents in samples from a human milk bank. The results showed concentration values between 0.5 and 10 μg mL(-1), with higher concentrations for the samples treated by pasteurisation. The effect of freezing time on the content of nucleotides was also assessed.
authors.affiliation: Analytical Chemistry, Nutrition and Food Science Department, University of Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Mateos-Vivas
authors.affiliation: Analytical Chemistry, Nutrition and Food Science Department, University of Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain. Electronic address: erg@usal.es.
authors.forename: Encarnación
authors.initials: E
authors.lastname: Rodríguez-Gonzalo
authors.affiliation: Analytical Chemistry, Nutrition and Food Science Department, University of Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Domínguez-Álvarez
authors.affiliation: Analytical Chemistry, Nutrition and Food Science Department, University of Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: García-Gómez
authors.affiliation: Technological Agri-Food Institute (INTAEX), Avda. Adolfo Suárez s/n, 06071 Badajoz, Spain.
authors.forename: Rosario
authors.initials: R
authors.lastname: Ramírez-Bernabé
authors.affiliation: Analytical Chemistry, Nutrition and Food Science Department, University of Salamanca, Plaza de los Caídos s/n, 37008 Salamanca, Spain.
authors.forename: Rita
authors.initials: R
authors.lastname: Carabias-Martínez
mesh_terms: D000249:Adenosine Monophosphate / Q000032:analysis; D003568:Cytidine Monophosphate / Q000032:analysis; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D008895:Milk, Human / Q000737:chemistry*; D009711:Nucleotides / Q000032:analysis*; D061352:Pasteurization; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D009711:Nucleotides; D000249:Adenosine Monophosphate; D003568:Cytidine Monophosphate
keywords: Capillary electrophoresis–electrospray ionisation-mass spectrometry; Centrifugal ultrafiltration; Freezing time; Human milk; Nucleotide monophosphates; Processing