A new sample preparation and separation combination for precise,accurate, rapid,and simultaneous determination of vitamins B1, B2, B3, B5, B6, B7, and B9 in infant formula and related nutritionals by LC-MS/MS

An improved method was developed for simultaneous determination of the fortified forms of thiamine (B₁), riboflavin (B₂), nicotinamide and nicotinic acid (B₃), pantothenic acid (B₅), pyridoxine (B₆), biotin (B₇), and folic acid (B₉) in infant formulas and related nutritionals. The method employed a simple, effective, and rapid sample preparation followed by liquid chromatography tandem mass spectrometry (LC-MS/MS). It improved upon previous methodologies by offering facile and rugged sample preparation with improved chromatographic conditions, which culminated in a highly accurate and precise method for water-soluble vitamin determination in a wide range of formulas. The method was validated over six days in ten unique matrices with two analysts and on instruments in two different labs. Intermediate precision averaged 3.4 ± 2.6% relative standard deviation and over-spike recovery averaged 100.2 ± 2.4% (n = 160). Due to refinements in sample preparation, the method had high sample throughput capacity.     

Simultaneous determination of eight B‐vitamins in rat intestinal perfusate to identify effects of osmotic pressures on absorptions

A rapid and accurate HPLC‐DAD method was developed and validated to simultaneously determine eight B‐vitamins (VBs, namely thiamine, riboflavin, niacinamide, calcium pantothenic, pyridoxine, biotin, folic acid and cyanocobalamin) and phenolsulfonphthalein in rat intestinal perfusate. Chromatographic separation was achieved using an Inertsil ODS‐3 column (250 × 4.6 mm i.d., 5 μm) at a temperature of 40°C. Gradient elution mode was applied at the flow rate of 1.0 mL/min with the mobile phase of acetonitrile–30 mm K₂HPO₄ (pH 5.80). The method was successfully applied to identify the effects of osmotic pressures on the absorption of the VBs. The absorption profiles of single and mixed VBs were also compared. Histological section technology was applied to observe the microstructure of small bowel mucosa after perfusion. The results indicated that each compound possessed a better absorption profile under isotonic conditions than under hypotonic or hypertonic conditions for single or mixed solutions. Compared with single VBs, better absorptions in mixed VBs were observed. Pathological tissue slice test suggested that hypotonic and hypertonic solutions changed or damaged the microstructure of mucosa to varying degrees. Taken together, the investigations indicated that multi‐VBs administered orally under isotonic condition could generate fast and complete absorption profiles for VBs.     

Quantum‐Assisted Metrology of Neutral Vitamins in the Gas Phase

It has recently been shown that matter‐wave interferometry can be used to imprint a periodic nanostructure onto a molecular beam, which provides a highly sensitive tool for beam displacement measurements. Herein, we used this feature to measure electronic properties of provitamin A, vitamin E, and vitamin K1 in the gas phase for the first time. The shift of the matter‐wave fringes in a static electric field encodes the molecular susceptibility and the time‐averaged dynamic electric dipole moment. The dependence of the fringe pattern on the intensity of the central light‐wave diffraction grating was used to determine the molecular optical polarizability. Comparison of our experimental findings with molecular dynamics simulations and density functional theory provides a rich picture of the electronic structures and dynamics of these biomolecules in the gas phase with β‐carotene as a particularly interesting example.     

Components of Certain Species of the Elaeagnaceae Family

Data from the last 50 years for various classes of compounds from certain plant species of the oleaster (Elaeagnaceae) family are reviewed     

Determination of the design space of the HPLC analysis of water‐soluble vitamins

Analysis of water‐soluble vitamins has been tremendously approached through the last decades. A multitude of HPLC methods have been reported with a variety of advantages/shortcomings, yet, the design space of HPLC analysis of these vitamins was not defined in any of these reports. As per the food and drug administration (FDA), implementing the quality by design approach for the analysis of commercially available mixtures is hypothesized to enhance the pharmaceutical industry via facilitating the process of analytical method development and approval. This work illustrates a multifactorial optimization of three measured plus seven calculated influential HPLC parameters on the analysis of a mixture containing seven common water‐soluble vitamins (B₁, B₂, B₆, B_12, C, PABA, and PP). These three measured parameters are gradient time, temperature, and ternary eluent composition (B1/B2) and the seven calculated parameters are flow rate, column length, column internal diameter, dwell volume, extracolumn volume, %B (start), and %B (end). The design is based on 12 experiments in which, examining of the multifactorial effects of these 3 + 7 parameters on the critical resolution and selectivity, was carried out by systematical variation of all these parameters simultaneously. The 12 basic runs were based on two different gradient time each at two different temperatures, repeated at three different ternary eluent compositions (methanol or acetonitrile or a mixture of both). Multidimensional robust regions of high critical R_s were defined and graphically verified. The optimum method was selected based on the best resolution separation in the shortest run time for a synthetic mixture, followed by application on two pharmaceutical preparations available in the market. The predicted retention times of all peaks were found to be in good match with the virtual ones. In conclusion, the presented report offers an accurate determination of the design space for critical resolution in the analysis of water‐soluble vitamins by HPLC, which would help the regulatory authorities to judge the validity of presented analytical methods for approval.     

Determination of Water Soluble Vitamins in Laboratory Animal Feeds by Micellar Electrokinetic Chromatography

Seven water-soluble vitamins: thiamine hydrochloride (B₁), riboflavin hydrochloride (B₂), pyridoxine hydrochloride (B₆), calcium pantotenate (B₅), ascorbic acid (C), folic acid (B₉), and biotin (H, B₇) were separated using the micellar electrokinetic chromatographic (MEKC) method in a single run with the electrolyte solution consisting of 100 mM H₃BO₃, 5 mM Na₂B₄O₇, and 30 mM sodium dodecylsulphate (SDS). The separation was achieved within 8 min. and the detection was performed at 200 nm. The calibration graphs plotted with six concentrations of each vitamin were linear with the determination coefficient r > 0.999. The method was applied for quantification of vitamins B₁, B₂, B₅, B₆, B₉, C, and H in novel feed for laboratory animals. The sample preparation involved solid-phase extraction of the vitamins, used prior to the MEKC analysis. The attained precision level was good with the recoveries between 98.4% and 105.6%. The simplicity of the procedure should make it highly useful for feed quality control in husbandry and the animal feed industry.     

Oligosaccharide Shells as a Decisive Factor for Moderate and Strong Ionic Interactions of Dendritic Poly(ethylene imine) Scaffolds under Shear Forces

For better understanding and improving the non‐covalent interactions of dendritic core–shell, we evaluated the interactions of hyperbranched poly(ethylene imine) (PEI) decorated with various oligosaccharide shells with water‐soluble B vitamins, an estradiol derivative and pantoprazole. Depending on the different properties of the analyte molecules, dendritic core–shell glyco architectures showed (very) weak, moderate and strong interactions with the analyte molecules. Thus, ionic interactions are the strongest driving force for the formation of host–guest complexes. The core–shell glyco architecture is a necessary prerequisite for stable analyte/PEI complexes; the pure hyperbranched PEI did not show any sufficiently strong interactions with neutral, cationic or anionic analytes under the shear forces applied during ultrafiltration of pure aqueous solution without an adjusted pH. Thus, only robust non‐covalent interactions between analytes and the dendritic polyamine scaffold of the glycopolymer structure survive this separation step and allow isolation of stable host–guest complexes in aqueous solution.     

Ion‐pair cloud‐point extraction: A new method for the determination of water‐soluble vitamins in plasma and urine

A novel, simple, and effective ion‐pair cloud‐point extraction coupled with a gradient high‐performance liquid chromatography method was developed for determination of thiamine (vitamin B₁), niacinamide (vitamin B₃), pyridoxine (vitamin B₆), and riboflavin (vitamin B₂) in plasma and urine samples. The extraction and separation of vitamins were achieved based on an ion‐pair formation approach between these ionizable analytes and 1‐heptanesulfonic acid sodium salt as an ion‐pairing agent. Influential variables on the ion‐pair cloud‐point extraction efficiency, such as the ion‐pairing agent concentration, ionic strength, pH, volume of Triton X‐100, extraction temperature, and incubation time have been fully evaluated and optimized. Water‐soluble vitamins were successfully extracted by 1‐heptanesulfonic acid sodium salt (0.2% w/v) as ion‐pairing agent with Triton X‐100 (4% w/v) as surfactant phase at 50°C for 10 min. The calibration curves showed good linearity (r² > 0.9916) and precision in the concentration ranges of 1‐50 μg/mL for thiamine and niacinamide, 5–100 μg/mL for pyridoxine, and 0.5–20 μg/mL for riboflavin. The recoveries were in the range of 78.0–88.0% with relative standard deviations ranging from 6.2 to 8.2%.