Liquid Chromatography Method for the Simultaneous Quantification of Biotin and Vitamin B12 in Vitamin B Supplements.

Background: The determination of cyanocobalamin (vitamin B12) and biotin has always been challenging because of the lack of a chromophore for biotin and trace level input for vitamin B12 in supplements. Microbiological assay methods are currently used for quantitation. However, these methods are time consuming, may lack specificity, and have high imprecision. Objective: Our laboratory developed and validated an LC method for the simultaneous quantitation of vitamin B12 and biotin. Methods: This LC method uses a single quadruple mass analyzer to detect biotin and vitamin B12 at m/z 245.10 and m/z 678.29, respectively. Results: The mass analyzer allows for low limits of quantitation (biotin: 1 ng/mL; vitamin B12: 4 ng/mL). Precision results showed that injections are repeatable without the use of an internal standard (RSD < 5%). Single analyst (n = 5: RSD < 3%), within lab (n = 10: RSD < 8%), and multilab (n = 20: RSD < 13%) precision results were also much better than those reported by microbiological assay methods. Linearity was evaluated between 92.00 ng/mL and 9200 ng/mL (R² 09916) for biotin and between 4.846 ng/mL and 484.6 ng/mL (R² 0.9999) for vitamin B12. The method is accurate between 20 ng/mL and 60 ng/mL for vitamin B12 and between 400 ng/mL and 1200 ng/mL for biotin. Conclusions: The results show a simple, accurate, and precise method for the quantitation of vitamin B12 and biotin. Highlights: This work demonstrates that single quadrupole mass analyzers can be successfully used to quantify trace level analytes in quality control laboratories.

Gromwell (Lithospermum erythrorhizon) root extract protects against glycation and related inflammatory and oxidative stress while offering UV absorption capability.

Glycation and advanced glycation end products (AGE) damage skin which is compounded by AGE-induced oxidative stress and inflammation. Lip and facial skin could be susceptible to glycation damage as they are chronically stressed. As Gromwell (Lithospermum erythrorhizon) root (GR) has an extensive traditional medicine history that includes providing multiple skin benefits, our objective was to determine whether GR extract and its base naphthoquinone, shikonin, might protect skin by inhibiting glycation, increasing oxidative defenses, suppressing inflammatory responses and offering ultraviolet (UV) absorptive potential in lip and facial cosmetic matrices. We show GR extract and shikonin dose-dependently inhibited glycation and enhanced oxidative defenses through nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element activation. Inflammatory targets, nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) and tumor necrosis factor alpha, were suppressed by GR extract and shikonin. Glyoxalase 1 (GLO1) and glutathione synthesis genes were significantly upregulated by GR extract and shikonin. GR extract boosted higher wavelength UV absorption in select cosmetic matrices. Rationale for the use of GR extract and shikonin are supported by our research. By inhibiting glycation, modulating oxidative stress, suppressing inflammation and UV-absorptive properties, GR extract and shikonin potentially offer multiple skin benefits.