Request for analytical method for B-complex vitamins determination in multivitamin juice matrices

Hi everyone,
Could anyone share a robust analytical method (UPLC/HPLC) for the simultaneous determination of water-soluble B-complex vitamins (B1, B2, B3, B5, B6, B7, and B9) in multivitamin juice products?
Standard Preparation & Sample Preparation: Stock/working solution preparation, diluents, stability, and extraction/clarification protocols for complex juice matrices.
Chromatographic Conditions: Recommended stationary phase (e.g., polar-embedded or reverse-phase C18 columns), mobile phase composition (buffers, organic modifiers, pH optimization), and gradient elution profiles.
Thanks