Tianyi Guan

About

This project investigated the separation and quantitative analysis of five nucleotide monophosphates in infant formula using complementary spectroscopic and chromatographic methods. AMP, UMP, GMP, CMP, and IMP were examined through calibration-based UV–Vis measurements and HPLC analysis following matrix-specific sample preparation. The study integrated standard preparation, acid-assisted matrix cleanup, centrifugation, filtration, chromatographic separation, and quantitative calibration to evaluate nucleotide composition in a complex food matrix.

Research Focus

To evaluate how complementary UV–Vis and HPLC workflows can be used to identify and quantify nucleotide monophosphates in infant formula while accounting for the analytical challenges introduced by a complex sample matrix.

Study Design

Calibration standards spanning sub-ppm to tens-of-ppm concentrations were prepared for AMP, UMP, GMP, CMP, and IMP. Infant-formula samples were dissolved, acidified, centrifuged, diluted, and syringe-filtered prior to analysis. UV–Vis measurements were collected at nucleotide-specific wavelengths, while HPLC analysis used chromatographic retention and peak integration for analyte-resolved quantitation. Non-spiked and nucleotide-spiked milk preparations were incorporated into the chromatographic workflow, and calibration relationships were used to back-calculate nucleotide concentrations in the analyzed sample.

Key Findings

Strong calibration behaviour was obtained across both analytical platforms. UV–Vis calibration coefficients ranged from R² = 0.9827–0.9999, while the five HPLC calibration curves achieved R² = 0.9994–0.9997. Chromatographic separation resolved the five nucleotide standards across distinct retention times, enabling analyte-specific quantitation in the milk matrix. The contrast between direct spectrophotometric and chromatographic measurements also highlighted the importance of analytical selectivity when quantifying structurally related compounds in complex food samples.

Key Methods

UV–Vis spectrophotometry; high-performance liquid chromatography (HPLC); external calibration; volumetric standard preparation; acid-assisted sample preparation; centrifugation; sonication; syringe filtration; chromatographic peak integration;

Keywords

Analytical chemistry; nucleotide analysis; infant formula; HPLC; UV–Vis spectroscopy; AMP; UMP; GMP; CMP; IMP; quantitative analysis; food analysis; chromatographic separation;

Project Status

Completed (2025)