Nuclear magnetic resonance technology is not only an excellent qualitative technique，but also has its unique advantages in quantitative aspects. As a highly selective，fast，and economical quantitative analysis method，nuclear magnetic quantification technology has been widely applied in fields such as medicine，chemical industry，and food. The basic principle of nuclear magnetic resonance quantitative technology is that the strength of the detected magnetic resonance signal is proportional to the number of corresponding nuclear. Based on the properties of the sample，corresponding technical means and quantitative methods can be flexibly selected，which have wide application value. This article provides a systematic summary of the quantitative methods of nuclear magnetic quantification technology combined with relevant literature reports and research results，providing reference for its practical application and research.

Objective: To establish an HPLC method for simultaneous determination of loganic acid, gentiopicroside, hesperidin, paeonol, aloe-emodin, rhein, emodin, chrysophanol and physcion in Tongshu Koushuang tablets (Rhei Radix et Rhizoma, Aurantii Fructus Immaturus and Gentianae Macrophyllae Radix, etc.). Methods: The samples were extracted by refluxing with methanol and the separation was performed on a Thermo Acclaim-C₁₈(250 mm×4.6 mm, 5 μm) column at 30 ℃, with mobile phase consisting of 0.15% phosphoric acid solution and acetonitrile with a gradient elution at a flow rate of 1.0 mL·min^-1. The injection volume was 10 μL, and the detection wavelength was set at 236 nm (detecting loganic acid), 280 nm (detecting gentiopicroside, hesperidin and paeonol) and 254 nm (detecting aloe-emodin, rhein, emodin, chrysophanol and physcion). Results: Nine constituents (loganic acid, gentiopicroside, hesperidin, paeonol, aloe-emodin, rhein, emodin, chrysophanol and physcion) were in good linearity within their own ranges (r were 0.999 1-0.999 9), and the average recoveries were 99.6% (RSD=1.9%), 101.1% (RSD=2.0%), 103.0% (RSD=1.5%), 101.6% (RSD=0.51%), 99.8% (RSD=1.4%), 100.9% (RSD=1.4%), 100.8% (RSD=1.8%), 102.7% (RSD=1.2%) and 102.9% (RSD=0.86%), respectively. The content ranges of nine constituents were 1.871-3.517 mg·g^-1, 6.274-12.55 mg·g^-1, 2.140-3.946 mg·g^-1, 1.393-2.018 mg·g^-1, 0.394 8-0.807 2 mg·g^-1, 0.657 5-1.246 mg·g^-1, 0.484 7-0.915 8 mg·g^-1, 0.839 8-1.429 mg·g^-1 and 0.327 3-0.547 9 mg·g^-1, respectively. Conclusion: This simple and accurate method can be used for the quality control and evaluation of Tongshu Koushuang tablets.

Objective: To explore the fragmentation patterns of synthetic cannabinoids by electron impact (EI) ionization mass spectrometry. Methods: Forty synthetic cannabinoids were systematically investigated by gas chromatography coupled to mass spectrometry (GC-MS). Ionization mode was EI (70 eV) and the acquisition range was m/z 50-600. Results: According to the different structures of the “head group” and “linked group”, forty synthetic cannabinoids were divided into six categories, namely cumyl-carboxamide type, adamantyl-carboxamide type, carbamoyl/methyl butyrate-carboxamide type, naphthylformyl type, benzoyl/phenylacetyl type and tetramethylcyclopropane-acyl type. Through the analysis of the mass spectrum of synthetic cannabinoids, the fragmentation pathways and characteristic ions of different types of synthetic cannabinoids were given. The main EI-MS fragmentation patterns of synthetic cannabinoids were that both sides of the carbonyl group in the “linking group” undergo α-cleavage, and the N atom on the indole/indazole parent nucleus was prone to γ-H rearrangement, and loss of a R₁. In addition, fragment ions m/z 116, 130, 144 and fragment ions m/z 117, 131, 145 were the characteristic fragments of indazole and indole parent nucleus, which could be used to identify the parent nucleus of synthetic cannabinoids. Conclusion: These kind of compounds have strong fragmentation regularity. When standard substances are lacking or commercial mass spectral libraries are difficult to obtain, the proposed synthetic cannabinoids EI-MS fragmentation pathways can help to rapidly identify the structures of unknown synthetic cannabinoids.

Objective: To establish a dual derivatization method combined with tandem mass spectrometry for the simultaneous determination of 18 different steroid hormones in human serum. Methods: Serum samples were treated with hydroxylamine and 1, 2-dimethylimidazole-5-sulfonyl chloride for derivatization, and the resulting compounds were analyzed by liquid chromatography-tandem mass spectrometry in positive ion selected reaction monitoring (SRM) mode. The Kinetex^®C₈ column (100 mm×2.1 mm, 2.6 μm) was used for the separation. Mobile phase A (0.1% acetic acid in water) and mobile phase B (0.1% acetic acid in methanol) with gradient elution（0-0.5 min, 35% B; 0.5-5 min, 35% B→100% B; 5.0-5.1 min, 100% B→35% B; 5.1-7 min, 35% B）at the flow rate of 0.4 mL·min^-1 were applied. Column temperature was set at 40 ℃. Injection volume was 20 μL and collection time was 6 min. Results: The linearity correlation coefficients for all 18 steroid hormones were greater than 0.99, the recovery rates ranged from 85% to 115%, and the precision RSD was less than 15%. This method was successfully applied to the analysis of serum samples from 156 healthy subjects (75 males and 61 females), and reference intervals were established. Conclusion: This method can be used to simultaneously determine 18 types of steroid hormones, such as pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone, corticosterone, cortisol, 11-deoxycorticosterone, 21-deoxycorticosterone, aldosterone, testosterone, androstanedione, dehydroepiandrosterone, sulfated dehydroepiandrosterone, adrenocorticotropin, 18-hydroxicorticotropin, estrone, estradiol, and estriol using non-solid-phase extraction.

Objective: To establish an UHPLC-MS/MS method for determining eight primary components （catechin, epigallocatechin, rutin, quercitrin, epicatechin, (+)-dihydromyricetin, myricitrin and dihydroqurcetin） in the young branches and leaves of Xanthoceras sorbifolia Bunge, a medicinal plant from Mongolia, and to compare their contents in samples at different growth stages. Methods: A Waters CORTECS C₁₈ (100 mm×2.1 mm, 1.6 μm) chromatographic column was adopted using the mobile phase comprised of water containing 0.1% formic acid (A) and acetonitrile (B) with gradient elution（0-1 min, 5% B; 1-10 min, 5% B→28% B; 10-11 min, 28% B→95% B; 11-14 min, 95% B; 14-15 min, 95% B→5% B） at a flow rate of 0.3 mL·min^-1. The temperature of the column was set at 40 ℃. Injecting volume was 2 μL. Detection was conducted using electrospray ionization (ESI) in negative ion mode with multiple reaction monitoring (MRM). Results: The linearity of the eight chemical components was found to be excellent in the tested concentration ranges, with correlation coefficients above 0.997 6. Precision, repeatability and stability were satisfactory and the average recoveries were between 97.4% and 106.0% with RSDs≤5.0%. In six batches of leaves, contents of catechin, epigallocatechin, rutin, quercitrin, epicatechin, (+)-dihydromyricetin, myricitrin and dihydroqurcetin were in the ranges of 0.090-0.904 mg·g^-1, 0.093-2.258 mg·g^-1, 0.001-0.005 mg·g^-1, 0.530-6.176 mg·g^-1, 0.158-1.561 mg·g^-1, 0.002-0.056 mg·g^-1, 4.008-10.218 mg·g^-1 and 1.049-16.990 mg·g^-1, respectively. In six batches of young branches, the contents ranged from 0.384-1.025 mg·g^-1, 0.911-2.427 mg·g^-1, 0.008-0.127 mg·g^-1, 0.870-2.295 mg·g^-1, 0.659-1.746 mg·g^-1, 0.125-1.079 mg·g^-1, 2.296-4.681 mg·g^-1 and 1.958-4.946 mg·g^-1, respectively. The contents of eight components varied a lot in samples from different parts. The contents of myricitrin, rutin and quercitrin in the leaves exhibited noticeable changes with the growth cycle, suggesting their potential as quality control markers for leaves of Xanthoceras sorbifolia. Conclusion: The method is accurate, sensitive, stable, repeatable, and suitable for simultaneous determination of eight components in Xanthoceras sorbifolia Bunge, offering reference for quality control of its leaves and branches.

Objective: To develop an HPLC method for determination of naphazoline hydrochloride, diphenhydram hydrochloride and lidocaine hydrochloride added in nasal cold compress gel (dew), and to establish an HPLC-triple quadrupole mass spectrometry (HPLC-MS) method to confirm the positive samples. Methods: The samples were extracted with acetonitrile, detected by high performance liquidchromatography, quantified by external standard method and confirmed by HPLC-MS. The separation was performed on a XTerra RP18 (150 mm×4.6 mm, 5 μm) column with the mobile phase consisting of 50 mmol·L^-1 ammonium acetate (the pH value was adjusted to 7.8 with acetic acid or ammonia solution)-acetonitrile (72∶28) at the flow rate of 1.0 mL·min^-1 and the detection wavelength was 230 nm. The analysis was performed on a BEH C₁₈ (100 mm×2.1 mm, 1.7 μm) column with a gradient elution of 0.1% formic acid aqueous solution-0.1% formic acid acetonitrile solution. The column temperature was set at 40 ℃ and the flow rate was 0.4 mL·min^-1. Electrospray ionization source was applied and operated in positive electrospray ionization and the multiple reaction monitoring mode. Results: The method showed the lowest detection concentrations of naphthazoline hydrochloride, diphenhydramine hydrochloride and lidocaine hydrochloride were 2.4 ng·mL^-1, 50 ng·mL^-1 and 50 ng·mL^-1. The sample recoveries ranged from 93.9% to 104.6%. Good linearities were found in the concentration range of 10-200 μg·mL^-1（r>0.999 0）. A total of 42 batches of samples were detected and the total positive rate was 70% (36/42). Naphthazoline hydrochloride were found in 34 batches. Diphenhydramine hydrochloride and lidocaine hydrochloride were found in 2 batches simultaneously. Conclusion: The established method is specific, sensitive, simple, accurate and reliable. It can be used for the qualitative and quantitative determination of naphthazoline hydrochloride, diphenhydramine hydrochloride and lidocaine hydrochloride in nasal cold compress gel (dew).