Determination of Vitamins K1, K2 MK-4, MK-7, MK-9 and D3 in Pharmaceutical Products and Dietary Supplements by TLC-Densitometry

Abstract

Vitamin K is a group of lipophilic molecules. Forms of vitamin K play an essential role in the activation of specific proteins involved in blood clotting cascade or bone metabolism. Another molecule belonging to the fat-soluble vitamins group that also plays an important role in calcium metabolism is vitamin D3. The dietary supplements containing vitamins K and D3 are one of the most frequently consumed by patients. The objective of this work was to develop a simple, fast and sensitive thin-layer chromatography (TLC)-densitometric procedure for the simultaneous quantitative analysis of vitamins K and D3 in pharmaceutical products and dietary supplements. The analysis of vitamins was performed on the silica gel RP-18 F₂₅₄s plates with methanol-ethanol-isopropanol in a volume ratio of 15:1:4 as a mobile phase. The densitometric measurements were made at 254 nm. The method was validated by checking the specificity, linearity, precision, recovery, limit of detection, limit of quantification and robustness in accordance with International Conference on Harmonization (ICH) guidelines. The method was shown to be specific, accurate (recoveries were from 95.78 to 104.96%), linear over the tested range (correlation coefficient, exceeding 0.99), and precise (precision and intermediate precision RSD below 2.70% for all analytes). The satisfactory results of the validation of the method indicate that it can be used in the quality control of dietary supplements and pharmaceutical products containing vitamins K and D3.

Processes and Interactions Impacting the Stability and Compatibility of Vitamin K and Gold Nanoparticles

“…The UV-Vis spectra of the media mentioned above are displayed in Figure 2. Similar spectra with those from the literature [37], were recorded for vitamin K1 analyzed in our study. Three absorption maxima of VK, at wavelengths (λ) of 332 nm, 268 nm, and 244 nm, can be observed in the NaF, NaCl, and NaBr solutions (Figure 2a-c; NaX-VK spectra), both in the absence and in the presence of AuNPs, suggesting that there are no instantaneous interactions, at first contact, between nanoparticles and halide ions.…”

“…Three absorption maxima of VK, at wavelengths (λ) of 332 nm, 268 nm, and 244 nm, can be observed in the NaF, NaCl, and NaBr solutions (Figure 2a-c; NaX-VK spectra), both in the absence and in the presence of AuNPs, suggesting that there are no instantaneous interactions, at first contact, between nanoparticles and halide ions. Absorption peaks are slightly shifted compared to those reported in the literature for vitamin K1, at 260 nm and 240 nm, respectively [37], due to the effects generated by Similar spectra with those from the literature [37], were recorded for vitamin K 1 analyzed in our study. Three absorption maxima of VK, at wavelengths (λ) of 332 nm, 268 nm, and 244 nm, can be observed in the NaF, NaCl, and NaBr solutions (Figure 2a-c; NaX-VK spectra), both in the absence and in the presence of AuNPs, suggesting that there are no instantaneous interactions, at first contact, between nanoparticles and halide ions.…”

“…Three absorption maxima of VK, at wavelengths (λ) of 332 nm, 268 nm, and 244 nm, can be observed in the NaF, NaCl, and NaBr solutions (Figure 2a-c; NaX-VK spectra), both in the absence and in the presence of AuNPs, suggesting that there are no instantaneous interactions, at first contact, between nanoparticles and halide ions. Absorption peaks are slightly shifted compared to those reported in the literature for vitamin K 1 , at 260 nm and 240 nm, respectively [37], due to the effects generated by the environment in which the analysis was performed. In all cases, both in the absence and in the presence of vitamin, the addition of AuNPs (absorption maximum highlighted at λ = 550 nm) [31], leads to the baseline shifting, more obvious in the case of environments based on NaCl and NaBr than in those based on NaF solution (Figure 2a-c).…”

Simultaneous Determination of Vitamins D3 (Calcitriol, Cholecalciferol) and K2 (Menaquinone-4 and Menaquinone-7) in Dietary Supplements by UHPLC

“…Various methods have been used for the determination of fat-soluble vitamins in different matrices such as biological fluids, foods, and plant material by, namely spectrophotometry, fluorimetry, electrochemistry, immunoassay, capillary electrophoresis, and chromatography [6,7,11,12]. Of these, the chromatographic methods such as thin-layer chromatography (TLC), gas chromatography (GC), and high-performance liquid chromatography (HPLC) with electrochemical, spectrophotometric, fluorimetric, or mass spectrometric detection methods are suitable and widely used for the determination of vitamins D3 and K2 [6,7,11,12]. When dealing with complex matrices, a comprehensive sample preparation is necessary to eliminate interferences in the HPLC method from other compound having chemical formulas and structures [6].…”

Photoinitiators from bio-sourced naphthoquinone – the application of naphthoquinone-based vitamins K1 and K3 in free radical photopolymerization

“…Similarly, the accuracy of the light absorption data of K1 was verified by comparing the absorption peak shape of K1 across multiple sources. 37,38 In contrast, juglone's light absorption was primarily concentrated at a wavelength of 430 nm. Compared to K3 and juglone, K1 exhibited much better light absorption performance ( ε max = 15 200 M −1 cm −1 ), which can be attributed to the presence of phytane (2,6,10,14-tetramethylhexadecane) in K1.…”