Structural Identification of Impurities in Pioglitazone Hydrochloride Preparations by 2D-UHPLC-Q-Exactive Orbitrap HRMS and Their Toxicity Prediction.

Pharmaceutical companies and regulatory agencies have more and more concerns for impurities in pharmaceuticals and their toxicity. In this work, heart-cutting two-dimensional ultrahigh-performance liquid chromatography (2D-UHPLC) in combination with high-resolution mass spectrometry (HRMS) was used, setting HRMS as positive mode of electrospray ionization to identify five impurities in pioglitazone hydrochloride preparations. With the heart-cutting 2D-UHPLC and online desalting technique, the structures of five impurities were deduced in an analysis of MSn data. And three of them, Impurity-2, Impurity-3, and Impurity-5, have never been reported before. The fragmentation patterns of five impurities were proposed on a basis of accurate mass and fragment ions in this study. Since the toxicity of impurities is relevant to their structures, toxicology of all five impurities was predicted by three software tools, and the result showed that these compounds have good safety profile.

[Determination of donkey skin ingredients in Asini Corii Colla by ultra-high performance liquid chromatography-tandem mass spectrometry].

In recent years, due to the shortage of donkey skin resources, the price of Asini Corii Colla has seen a rapid increase. Consequently, fake gelatin prepared from horse, mules, pig, and cow skin has appeared in the market, resulting in unreliable quality of Asini Corii Colla. Therefore, there is an urgent need to develop an efficient and accurate method for improving the quality of Asini Corii Colla. Ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to determine the donkey skin components in Asini Corii Colla. Accordingly, 0. l g of the evenly mixed sample was weighed and placed in a 50 mL volumetric flask; then, 1% ammonium bicarbonate solution was added to dissolve the sample, and the solution was diluted to the scale. Precisely 1.00 mL of the solution was extracted into a 5 mL volumetric flask, followed by the addition of 1.0 mL trypsin solution and 100 µL mixed internal standard working solution. This mixture was diluted to the scale using 1% ammonium bicarbonate solution, shaken, and placed in an incubator for 16 h to induce enzymolysis at a constant temperature of 37 ℃. The mixture was subsequently removed from the incubator, cooled to ambient temperature, filtered through a 0.22 µm membrane, and analyzed by LC-MS. Separation was performed on an UPLC system with a BEH C18 column (100 mm×2.1 mm, 2.5 µm) under gradient elution using acetonitrile containing 0.1% (v/v) formic acid (B) and water containing 0.1% (v/v) formic acid (A) as the mobile phases at a flow rate of 0.3 mL/min. The column temperature was 30 ℃, and the sample size was 2 µL. The gradient elution conditions are: 0-1 min, 10%B; 1-5 min, 10%B-30%B; 5-5.1 min, 30%B-70%B; 5.1-7 min, 70%B; 7-7.1 min, 70%B-10%B; 7.1-10 min, 10%B. The marker peptides were determined in positive electrospray ionization (ESI +) and multiple reaction monitoring (MRM) modes using the isotopic internal standard method. The optimized enzymolysis conditions were as follows: enzymolysis temperature, 37 ℃; enzymolysis time, 16 h; and amount of enzyme, 1 mL. The two marker peptides showed good linearities in the range of 50 to 1250 mg/L; the correlation coefficients (r) were greater than 0.996, and the limits of quantitation (S/N=10) were 20 mg/kg. At spiked levels of 300 mg/kg, 600 mg/kg, and 900 mg/kg, the average recovery ratios of the two marker peptides were 103.2% to 108.3%, while the relative standard deviations (RSDs) of 1.0%-3.0%. This method was favorable for testing actual samples. Asini Corii Colla from 29 production companies was detected by this method, and the sum contents of the two marker peptides was different because the production process and raw materials were different. The sum contents of the samples were 0.096% to 0.180% with an average of 0.151%. The developed method is simple, reliable, and reproducible, and it is suitable for detecting the donkey hide components Asini Corii Colla.

[Determination of sennoside B, sennoside A and physcion in slimming health foods].

OBJECTIVE: To establish a quantitative analysis method for sennoside A, sennoside B and physcion by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). METHODS: The sample was extracted by methanol-2 mmol/L ammonium formate(9∶1) at 40 ℃ for 1 h. The separation was performed using Agilent Eclipse Plus C_(18 )(2. 1 mm × 50 mm, 1. 8 µm) column with gradient elution. The mobile phase was consisted of 0. 1% formic acid and methanol. Qualitative and quantitative analysis was conducted with an electrospray ionization source operated in the negative ionization(ESI~-) mode and multiple reaction monitoring(MRM) mode. RESULTS: The linear range of three compounds were from 0. 1 to 10 µg/mL with the correlation coefficients(r) above 0. 995. The spiked recoveries were in the range of 81. 9% to 114. 5% at the concentrations of 0. 02, 0. 15 and 1. 60 mg/g with relative standard devisions(RSDs) ranged from 0. 30% to 3. 43%(n=6). The detection limits of sennoside A and sennoside B were 1. 2 µg/g. The detection limit of physcion was 2. 4 µg/g. Sennoside A, sennoside B or physcion were detected in 19 out of 40 batches of samples. The content of sennoside A ranged from 0. 184 to 6. 33 mg/g and the content of sennoside B ranged from 0. 202 to 7. 23 mg/g. The content of physcion ranged from 0. 042 to 0. 79 mg/g. CONCLUSION: The method is simple, accurate and suitable for the determination of sennoside A, sennoside B and physcion.