GlcNAcβ1-3Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAc 

GlcNAcβ1-3Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAc  (lacto-N-neotetraose extended, LNT-II dimer/poly-LacNAc tetrasaccharide) manifests as a white lyophilized powder forming the repeating type 2 N-acetyllactosamine backbone essential for human milk oligosaccharide synthesis, leukocyte adhesion cascades, and tumor glycan biomarker research. This linear tetrasaccharide [GlcNAcβ1-3Galβ1-4GlcNAc]₂ serves as universal scaffold for fucosylation (Le^x/Le^a), sialylation (sialyl-LacNAc), and galactosylation (α-Gal), comprising 3-8% of total HMOs while dominating adult i-antigen structures on erythrocytes and granulocytes; chemoenzymatically scalable via iterative β3GnT2/β4GalT1 cycles (>98% purity), it mediates E-selectin/P-selectin dependent neutrophil rolling (KD 50-200 μM), demonstrates gastric stability with Bifidobacterium bifidum selective utilization yielding acetate/propionate, and supports NEC prophylaxis, cognitive ganglioside mimicry, cancer glycoengineering, and anti-metastatic selectin inhibitors, exhibiting >60-month desiccated stability. Appearance White crystalline/amorphous lyophilized powder, odorless. Exceptional water solubility (>500 g/L); stable clear solutions pH 5.5-8. ​ Source 3-8% mature human milk oligosaccharides; dominant poly-LacNAc on leukocytes. Biosynthetic via iterative β1-3GlcNAc/β1-4Gal transferases on LNT-II. ​ Molecular Weight and Structure 1054.0 g/mol, formula C₄₂H₇₁N₄O₃₁ (tetrasodium salt). Linear repeating [GlcNAcβ1-3Galβ1-4GlcNAc]₂ type 2 chain scaffold. ​ Sugar Specificity High-affinity E/P-selectin ligands; precursor for poly-sLeX/Le^x chains. Bifidobacterium β3GlcNAc-ase + Bacteroides β4Gal-ase hydrolysis. ​ Biological Activity Essential neutrophil rolling ligand; tumor immune evasion scaffold. Prebiotic stimulating B. longum subsp. infantis butyrate production. ​ Purity and Microbial Contamination ≥99% HPLC/NMR anomeric purity; endotoxins <2 EU/mg validated. Sterile; heavy metals <0.2 ppm; residual moisture <2%. ​ Identity and Quality Control ¹H-NMR confirms β-linkages (H1 4.45-4.75 ppm); LC-MS [M-4H]⁴⁻ 262. HPAEC-PAD Gal:GlcNAc 2:2 stoichiometry; α/β anomer <1:99. ​ Shelf Life and Storage 60+ months ambient desiccated; 10+ years -20°C lyophilized. N₂ sealed; <40% RH prevents hydrolytic degradation. ​ Applications Human milk oligosaccharide synthesis scaffold; glycan microarray standards. Selectin inhibitor screening; cancer glycomimetic engineering. ​ Key Characteristics Perfect type 2 chain repeating unit; universal glycan extension scaffold. Gastric/pancreatic hydrolase resistant; distal colon targeted. ​ Citation Links https://pubchem.ncbi.nlm.nih.gov/compound/91855153 ​ https://academic.oup.com/glycob/article/13/5/387/602770 ​ https://patents.google.com/patent/CN100509830C/en ​ https://pmc.ncbi.nlm.nih.gov/articles/PMC4672149/ ​ https://www.sciencedirect.com/science/article/pii/S0021925819597149 ​ https://www.tcichemicals.com/BE/en/p/G0351 ​ https://pubchem.ncbi.nlm.nih.gov/compound/91848165 ​ https://glycosmos.org/structure/poly-LacNAc-tetrasaccharide ​ https://www.cd-bioglyco.com/lnnt-tetrasaccharide ​ https://pmc.ncbi.nlm.nih.gov/articles/PMC6717531/ ​