[Quantitative NMR spectroscopy and its application in quality control of Chinese medicinal injection].

Chinese medicinal injection, made of active components extracted from Chinese medicine or Chinese medicinal compound, is a novel dosage form of Chinese patent medicine in China and is pivotal in the traditional Chinese medicine(TCM) industry. The quality control standard of Chinese medicinal injection determines its safety and efficacy. The quantitative nuclear magnetic resonance(qNMR) spectroscopy is a non-targeted, non-invasive, and non-destructive technique with high reproducibility, short measurement time, convenient sample preparation, a broad range of linearity, and no requirement on the reference substance of tested components, which is advantageous as compared with traditional chromatographic methods, and it can provide information about the molecular composition of the tested samples. Therefore, in light of multiple challenges in the quality control of Chinese medicinal injection, such as complex composition, difficulties in quantitative analysis, and the shortage of reference substances, the application of qNMR spectroscopy combined with chemometrics techniques was proposed for the quality evaluation of Chinese medicine reference substances, Chinese medicinal injection, and intermediates in the production process, as well as for the stability analysis of Chinese medicinal injection. This study is expected to provide references for the application of qNMR spectroscopy in the quality control of Chinese medicinal injection.

[Quality evaluation of ginsenoside reference substances based on qNMR spectroscopy].

The present study established a quality evaluation method for ginsenoside reference substances based on quantitative nuclear magnetic resonance(qNMR) spectroscopy. ~1H-NMR spectra were collected on Bruker Avance Ⅲ 500 MHz NMR spectrometer equipped with a 5 mm BBO probe. The acquire parameters were set up as follows: pulse sequence of 30°, D_1=20 s, probe temperature= 303 K, and the scan number = 32. Dimethyl terephthalate, a high-quality ~1H-qNMR standard, was used as the internal standard and measured by the absolute quantitative method. Methyl peaks of comparatively good sensitivity were selected for quantification, and linear fitting deconvolution was adopted to improve the accuracy of integration results. The qNMR spectroscopy-based method was established and validated, which was then used for the quality evaluation of ginsenoside Rg_1, ginsenoside Re, ginsenoside Rb_1, ginsenoside Rd, and notoginsenoside R_1. The results suggested that the content of these ginsenoside reference standards obtained from the qNMR spectroscopy-based method was lower than that detected by the normalization method in HPLC provided by the manufacturers. In conclusion, the qNMR spectroscopy-based method can ensure the quality of ginsenoside reference substances and provide powerful support for the accurate quality evaluation of Chinese medicine and its preparations. The qNMR spectroscopy-based method is simple, rapid, and accurate, which can be developed for the quantitative assay of Chinese medicine standard references.

[Fingerprint of Shenmai Injection based on ~1H-NMR technique].

Shenmai Injection is a Chinese medicinal injection prepared from Ginseng Radix et Rhizoma Rubra and Ophiopogonis Radix, which is widely used in clinical practice for the treatment and adjuvant therapy of cardiovascular diseases with significant pharmacological effects. Proton nuclear magnetic resonance spectroscopy(~1H-NMR) has the advantages of simple and nondestructive sample pretreatment, fast analysis, abundant chemical information, quantification and no need to follow the standard curve. It is widely used in the analysis and research of complex mixtures of traditional Chinese medicine, clinical blood and urine samples. In this study, the ~1H-NMR fingerprint of Shenmai Injection was established. Thirty-two chemical components were identified, including seven amino acids, eight small molecular organic acids, one alkaloid, four sugars, two nucleosides, seven saponins, and three other components. Pearson's correlation coefficient and multivariate analysis of variance(principal component analysis combined with hierarchical cluster analysis) were applied based on the ~1H-NMR fingerprint to evaluate the quality consistency. The results showed high-quality consistency of 82 batches of Shenmai Injection. This study confirms that the ~1H-NMR fingerprint has great potential in the application of quality control of Chinese medicinal injection.

[~1H-qNMR quantification of total ginsenosides in Shenmai Injection].

A content determination method based on ~1H-qNMR was developed for the determination of total ginsenosides in Shenmai Injection. The parameters were optimized with CD_3OD as the solvent, dimethyl terephthalate as the internal standard, the peak at δ 8.11 as the internal standard peak, and the peaks at δ 1.68 and δ 0.79 as quantitative peaks of total ginsenosides. The developed ~1H-qNMR-based method was validated methodologically. The results showed that the method could achieve accurate measurement of total ginsenosides in Shenmai Injection in the range of 0.167 6-3.091 1 mmol·L~(-1). The developed ~1H-qNMR-based method for total ginsenosides is simple in operation, short in analysis time, strong in specificity, independent of accompanying standard curve, and small in sample volume, which can serve as a reliable mean for the quality control of Shenmai Injection. This study is expected to provide new ideas for the development of quantification methods of total ginsenosides.

[NMR method for simultaneous determination of 21 chemical components in Danhong Injection].

Danhong Injection, a compound Chinese medicine injection prepared from Salviae Miltiorrhizae Radix et Rhizoma and Carthami Flos, is used in the clinical treatment of coronary heart disease, cerebral thrombosis, myocardial infarction, angina pectoris and other cardiovascular and cerebrovascular diseases. In this study, a quantitative method for simultaneous determination of multiple components in Danhong Injection was developed based on ~1H-qNMR technology and then methodological verification was carried out. The results showed that the established method had good methodological indexes. This method can simultaneously determine the content of 21 chemical components including 6 amino acids, 4 small molecular organic acids, 5 sugars and their derivatives, 1 nucleoside, and 5 aromatic compounds in Danhong Injection. The total content accounted for about 85% of the total solid mass, which reflected the great advantage of ~1H-qNMR method in the analysis of Chinese medicine injections. The ~1H-qNMR method for simultaneous determination of multiple components in Danhong Injection developed in this study has simple operation, short analysis time, and wide application range, which has practical significance for the quality evaluation of Danhong Injection and provides reference for the development of quality control methods for Chinese medicine injections.

[Study on rapid quality analysis method of Shengxuebao Mixture].

A rapid analysis method based on ultraviolet-visual(UV-Vis) spectroscopy, near infrared(NIR) spectroscopy and multivariable data analysis was established for quality evaluation of Shengxuebao Mixture. The contents of eight active ingredients of Shengxuebao Mixture including albiflorin, paeoniflorin, 2, 3, 5, 4'-tetra-hydroxy-stilbene-2-O-ß-D-glucopyranoside, specnuezhenide,ecliptasaponin D, emodin, calycosin-7-glucoside and astragaloside Ⅳ were simultaneously detected by using this method. HPLC-UV-MS was used as a reference method for determining the contents of these ingredients. Partial least squares(PLS) analysis was implemented as a linear method for multivariate models calibrated between UV spectrum/NIR spectrum and contents of 8 ingredients. Finally, the performance of the model was evaluated by 24 batches of test samples. The results showed that both UV-Vis and NIR models gave a good calibration ability with an R~2 value above 0.9, and the prediction ability was also satisfactory, with an R~2 value higher than 0.83 for UV-Vis model and higher than 0.79 for NIR model. The overall results demonstrate that the established method is accurate, robust and fast, therefore, it can be used for rapid quality evaluation of Shengxuebao Mixture.

[Quantitative analysis method of Shengxuebao Mixture by HPLC-UV-MS based on quality by design concept].

In this study, the HPLC-UV-MS method for the simultaneous determination of eight active ingredients of Shengxuebao Mixture were developed based on the concept of quality by design（QbD）with a stepwise optimization approach. After the analytical target profile（ATP）had been defined, albiflorin, paeoniflorin, 2, 3, 5, 4'-tetra-hydroxy-stilbene-2-O-ß-D-glucopyranoside, specnuezhenide, ecliptasaponin D, emodin, calycosin-7-glucoside, and astragaloside Ⅳ were identified as the indicator components. The resolution and the signal-to-noise ratio of indicator components were then selected as critical method attributes (CMA) for the first step optimization. According to the results collected from fractional factorial design, critical method parameters (CMP) were determined with a multiple linear regression method, which included the amount of acid addition in the mobile phase, temperature, gradient, and wavelength. After that, the amount of acid addition and the wavelength were optimized to improve the resolution and the signal-to-noise ratio of the indicator components. The peak symmetry factors of specnuezhenide and emodin were then set as CMA for the second step optimization. The Box-Behnken designed experiments were conducted. The temperature and gradient were optimized after modelling. The design space were calculated and verified. The optimized analytical method was validated, and the results showed a good precision, accuracy and stability, which means that it can be used for the quantification of the indicator components in Shengxuebao Mixture.

[Optimization of lime milk precipitation process of Lonicera Japonica aqueous extract based on quality by design concept].

Design space approach was applied in this study to optimize the lime milk precipitation process of Lonicera Japonica (Jinyinhua) aqueous extract. The evaluation indices for this process were total organic acid purity and amounts of 6 organic acids obtained from per unit mass of medicinal materials. Four critical process parameters (CPPs) including drop speed of lime milk, pH value after adding lime milk, settling time and settling temperature were identified by using the weighted standardized partial regression coefficient method. Quantitative models between process evaluation indices and CPPs were established by a stepwise regression analysis. A design space was calculated by a Monte-Carlo simulation method, and then verified. The verification test results showed that the operation within the design space can guarantee the stability of the lime milk precipitation process. The recommended normal operation space is as follows： drop speed of lime milk of 1.00-1.25 mL•min⁻¹, pH value of 11.5-11.7, settling time of 1.0-1.2 h, and settling temperature of 10-20 ℃..

[Residue Concentration and Distribution Characteristics of Perfluorinated Compounds in Surface Water from Qiantang River in Hangzhou Section].

This study studied the pollution characteristics of perfluorinated compounds (PFCs) in Qiantang River in Hangzhou section (QR). Surface water samples, collected in July 2014 and January 2015 from 14 sites in QR were analyzed for 16 PFCs. All samples were prepared by solid-phase extraction with Oasis WAX cartridges and analyzed using the ultra performance liquid chromatography interfaced to tandem mass spectrometry ( UPLC-MS/MS). The results showed that 8 medium-and short-chain PFCs including C4 and C8 perfluorinated sulfonates (PFSAs) and C4-C9 perfluorinated carboxylic acids (PFCAs) were detected in the surface waters. The total concentrations of PFCs ranged from 0.98 to 609 ng · L⁻¹, while perfluorooctanoic acid (PFOA) dominated, with range of 0.59-538 ng L⁻¹, and perfluorooctane sulfonate (PFOS) was detected at lower levels, ranging from 0 to 2.48 ng · L⁻¹. The spatial distribution of PFCs varied, and the pollutant concentrations at the sampling sites located in upstream of the river such as Lanjiangkou and Jiangjunyan were relatively high, PFCs concentration showed a decreasing trend from the upstream to the downstream. According to the ratio of feature components, PFCs in surface water of QR originated largely from the input of direct sewage emissions. Taken together, the PFCs pollution was highly correlated with the upstream of Qiantang River valley's industry distribution, and most of the mass load in the investigated river was attributed to upstream running water with a minor influence from the wastewater discharges along the river basin. Overall, the results presented here indicated that greater attention should be given to the contamination of PFCs, especially for PFOA in water body of QR.

Simultaneous determination of ginsenosides in Panax ginseng with different growth ages using high-performance liquid chromatography-mass spectrometry.

The contents of ginsenosides in Panax ginseng not only vary in different parts of the root, but also exhibit yearly variation. In this study, an HPLC-MS method was established in order to simultaneously analyse ginsenosides Rb1, Rb2, Rb3, Rc, Rd, Re, Rf, Rg1 and Rg2. The concentration of ginsenosides in the tap root and root fibre were compared and the yearly variations of nine ginsenosides elucidated. The results indicate that the total content of ginsenosides in the main root and the root fibre both attain a maximum level in the fourth year of growth, although the amount in the former is much higher than in the latter. The variation in the content of ginsenosides during a 2-6 year period suggests that cultivated P. Ginseng can be harvested after the fourth year. The current results will provide useful information for the quality control and good agricultural practice farming of ginseng.

Identification and analysis of absorbed and metabolic components in rat plasma after oral administration of 'Shuangdan' granule by HPLC-DAD-ESI-MS/MS.

A valid method using liquid chromatography-diode array detection-electrospray ionization (ESI) ion trap mass spectrometry was established for the study of the absorbed and metabolic components of a Chinese medicine 'Shuangdan' granule in rat plasma after oral administration. The plasma samples were acidified with 1M hydrochloric acid and extracted with ethyl acetate (EtOAc) of two-fold volume for three times. The chromatographic separation was carried out on a Zorbax SB-C18 column with a linear gradient whereas 0.1% acetic acid/water/acetonitrile was used as mobile phase. Mass spectra were acquired in both negative and positive modes. More than 20 components including 16 components from 'Shuangdan' granule and 5 metabolites were simultaneously identified by comparing their mass spectra and retention behavior with reference compounds or literature data. The results proved that the established method could be used to identify the structure of active components responsible for the pharmacological effects of 'Shuangdan' granule.