Profiling the differential phosphoproteome between breast milk and infant formula through a titanium (IV)-immobilized magnetic nanoplatform

• Published in: Food chemistry 2025-02, Vol.464 (Pt 1), p.141541, Article 141541
• Main Authors: Xie, Pengcheng, Liu, Jialiang, Liao, Zonggao, Zhou, Qi, Sun, Jiajiu, Liu, Zheyi, Xiong, Huihuang, Wan, Hao
• Format: Article
• Language: English
• Subjects: Breast milk and infant formula; Female; Graphite - chemistry; Humans; Infant; Infant Formula - analysis; Infant Formula - chemistry; Milk, Human - chemistry; Phosphopeptides - analysis; Phosphopeptides - chemistry; Phosphoproteins - analysis; Phosphoproteins - chemistry; Phosphoproteins - metabolism; Phosphoproteome; Proteome - analysis; Proteome - chemistry; Selectivity; Sensitivity; Tandem Mass Spectrometry; Titanium (IV)-immobilized magnetic nanoplatform; Titanium - chemistry
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2024.141541

Breast milk (BM) fulfills the nutritional needs of infants and sets the standard for infant formula (IF). However, profiling the differential phosphoproteome between BM and IF remains unclear. Herein, a titanium (IV) (Ti4+)-immobilized magnetic nanoplatform (Fe3O4@GO@PDA-Ti4+) was constructed by self-assembly polymerization of dopamine on magnetic graphene oxide, followed by immobilizing Ti4+ through chelation for phosphopeptide enrichment. Fe3O4@GO@PDA-Ti4+ possessed outstanding selectivity (1/1000, a molar ratio of β-casein digests to bovine serum albumin digests) and favorable sensitivity (2.5 fmol/μL), along with rapid magnetic separation. Excellent phosphopeptide capture efficiencies were obtained for BM and IF using Fe3O4@GO@PDA-Ti4+ as an adsorbent coupled with liquid chromatography-mass spectrometry/mass spectrometry. There were 191 and 239 phosphopeptides found in BM and IF, respectively, with 36 phosphoproteins identified in both. However, BM and IF shared only 17 phosphopeptides and 4 phosphoproteins. The variation in the phosphoproteome between BM and IF provides valuable insights into the optimization of IF humanization. •Fe3O4@GO@PDA-Ti4+ was fabricated to demonstrate a well-organized structure.•Fe3O4@GO@PDA-Ti4+ selectively enriched phosphopeptides under magnetic separation.•191 and 239 phosphopeptides were identified in BM and IF, respectively.•BM and IF shared only 17 phosphopeptides and 4 phosphoproteins in common.