Chemometrics for comprehensive analysis of nucleobases, nucleosides, and nucleotides in Siraitiae Fructus by hydrophilic interaction ultra high performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry

Liquid chromatography method for simultaneous quantification of ATP and its degradation products compatible with both UV-Vis and mass spectrometry

ATP and its degradation products are essential metabolic and signaling molecules. Traditionally, they have been quantified via high-performance liquid chromatography (HPLC) with UV-Vis detection while utilizing phosphate buffer mobile phase, but this approach is incompatible with modern mass detection. The goal of this study was to develop an ultra-performance liquid chromatography (UPLC) method free of phosphate buffer, to allow for analysis of adenine nucleotides with UV-Vis and mass spectrometry (MS) simultaneously. The final conditions used an Acquity HSS T3 premier column with a volatile ammonium acetate buffer to successfully separate and quantify ATP-related analytes in a standard mixture and in extracts from non-contracted and contracted mouse hindlimb muscles. Baseline resolution was achieved with all 10 metabolites, and a lower limit of quantification down to 1 pmol per inject was observed for most metabolites using UV-Vis. Therefore, this method allows for the reliable quantification of adenine nucleotides and their degradation products via UV-Vis and their confirmation and/or identification of unknown peaks via MS.

Nicotine in Complex Samples: Recent Updates on the Pretreatment and Analysis Method

Nicotine is a significant evaluation index of tobacco and its related products' quality, but nicotine overdose can pose serious health hazards and cause addiction and dependence, thus it can be seen that it is necessary to find suitable and efficient detection methods to precisely detect nicotine in diverse samples and complex matrices. In this review, an updated summary of the latest trends in pretreatment and analytical techniques for nicotine is provided. We reviewed various sample pretreatment methods, such as solid phase extraction, solid phase microextraction, liquid phase microextraction, QuEChERS, etc., and diverse nicotine assay methods including liquid chromatography, gas chromatography, electrochemical sensors, etc., focusing on the developments since 2015. Furthermore, the recent progress in the applications and applicability of these techniques as well as our prospects for future developments are discussed.HighlightsUpdated pretreatment and analysis methods of nicotine were systematically summarized.Microextraction and automation were main development trends of nicotine pretreatment.The introduction of novel materials added luster to nicotine pretreatment.The evolutions of ion source and mass analyzer were emphasized.

Application of a HPLC-Q/TOF method with post-column compensation for separation and identification of polar impurities in Cytidine disodium triphosphate for injection

Background:

Cytidine Disodium Triphosphate (CTP-2Na) for injection is mainly used for treating nervous system diseases. Currently, there are few studies focused on the separation and identification of polar impurities in CTP-2Na for injection, which is important for ensuring drug safety and efficacy.

Objective:

The study aimed to establish an HPLC-Q/TOF method for the separation and identification of polar impurities in CTP-2Na for injection.

Methods:

Chromatographic separation was achieved on a Waters Atlantis T3 column using 5 mM aqueous ammonium acetate solution as the mobile phase in an isocratic elution mode. A postcolumn compensation technology was used to improve the ionization efficiency of impurities in the spray chamber.

Results:

Three polar impurities (disodium cytidine tetraphosphate, disodium cytidine diphosphate, disodium cytidine monophosphate) were detected in CTP-2Na for injection. The former one is probably the overreaction product during the production of CTP-2Na, the latter two were reported as degradation products. The fragmentation patterns of cytidine phosphate compounds in negative ion mode are summarized.

Conclusion:

This study provides a good reference for the separation and identification of polar impurities in nucleotide drugs.

Traceability of the geographical origin of Siraitia grosvenorii based on multielement contents coupled with chemometric techniques

Siraitia grosvenorii (LHG) is widely used as a medicinal and edible material around the world. The objective of this study was to develop an effective method for the authentication of the geographical origin of LHG in its main producing area Guangxi, China, which is identified as Chinese Protected Designation of Origin product, against other producing regions in China. The content of 14 elements (K, Na, Ca, P, Mg, Al, B, Ba, Cu, Fe, Mn, Ni, Zn, and Sr) of 114 LHG samples was determined by inductively coupled plasma optical emission spectrometry. Multivariate analysis was then performed to classify the geographical origin of LHG samples. The contents of multielement display an obvious trend of clustering according to the geographical origin of LHG samples based on radar plot and principal component analysis. Finally, three supervised statistical techniques, including linear discriminant analysis (LDA), k-nearest neighbours (k-NN), and support vector machine (SVM), were applied to develop classification models. Finally, 40 unknown LHG samples were used to evaluate the predictive ability of model and discrimination rate of 100%, 97.5% and 100% were obtained for LDA, k-NN, and SVM, respectively. This study indicated that it is feasible to attribute unknown LHG samples to its geographical origin based on its multielement content coupled with chemometric techniques.

An Overview of Pretreatment and Analysis of Nucleotides in Different Samples (Update since 2010)

Nucleotides, which are important low-molecular-weight compounds present in organisms, are precursors of nucleic acids and participate in various regulatory and metabolic functions. Sensitive and valid methods for monitoring and determining nucleotides and nucleosides in different samples are urgently required. Due to the presence of numerous endogenous interferences in complex matrices and the high polarity of the molecules of the phosphate moiety, the determination of nucleotide content is challenging. This review summarizes the pretreatment and analysis methods of nucleotides in different samples. Advanced pretreatment methods, including different microextraction methods, solid-phase extraction based on novel materials, QuEChERS, are clearly displayed, and continuous progress which has been made in LC, LC-MS/MS and capillary electrophoresis methods are discussed. Moreover, the strengths and weaknesses of different methods are discussed and compared. Highlight:Advanced pretreatment and detection methods of nucleotides were critically reviewed.Microextraction technology was one of the trends of nucleotides pretreatment in the future.Applications of novel materials and supercritical fluid were highlighted.The evolution and advance of HRMS analyzers were in detailed.

One-Pot Derivatization for Wide-Scope Detection of Nucleobases and Deoxyribosides in Natural Medicinal Foods with Liquid Chromatography-Tandem Mass Spectrometry

A new chemical labeling-based LC-MS/MS approach was developed for quantitative profiling of nine canonical bases and deoxynucleosides (dNs) in natural products. Using 2-bromo-1-(4-dimethylamino-phenyl)-ethaone (BrDPE) as the tagging reagent, a previously unexploited N-alkylpyrimidine derivative (Nad) was created for one-pot labeling of widescope nucleobases via a flexible bromophilic substitution under mild conditions. The derivatization notably improved the LC-MS detection sensitivity by 31-107 fold, enabling a fast dilute-and-shoot analysis of highly diluted samples. The optimized and validated method demonstrated satisfactory accuracy (87-107%), precision (RSDs < 7.5%), and recovery (89-105%) for matrix-matched standard addition. The method was applied to simultaneously determine all target analytes and four uncanonical analogues and base-modified species in seven traditional health foods, which differ in contents by up to 600-fold for discrimination among samples. Further, the base-labeled Nads exhibit a unique fragmentation signature that could be used for untargeted screening of nucleobase-containing metabolites by simplified LC-MS/MS workflow to improve quality evaluation of natural medicinal products.

Simultaneous Quantification of Nucleosides and Nucleotides from Biological Samples

We report a reverse phase chromatography mass spectrometry (LC-MS) method for simultaneous quantification of nucleosides and nucleotides from biological samples, where compound identification was achieved by a tier-wise approach and compound quantification was achieved via external calibration. A total of 65 authentic standards of nucleosides and nucleotides were used for the platform development. The limit of detection (LOD) of those compounds ranged from 0.05 nmol/L to 1.25 μmol/L, and their limit of quantification (LOQ) ranged from 0.10 nmol/L to 2.50 μmol/L. Using the developed method, nucleosides and nucleotides from human plasma, human urine, and rat liver were quantified. Seventy-nine nucleosides and nucleotides were identified from human urine and 28 of them were quantified with concentrations of 13.0 nmol/L-151 μmol/L. Fifty-five nucleosides and nucleotides were identified from human plasma and 22 of them were quantified with concentrations of 1.21 nmol/L-8.54 μmol/L. Fifty-one nucleosides and nucleotides were identified from rat liver and 23 were quantified with concentrations of 1.03 nmol/L-31.7 μmol/L. These results demonstrate that the developed method can be used to investigate the concentration change of nucleosides and nucleotides in biological samples for the purposes of biomarker discovery or elucidation of disease mechanisms.

Analysis of the Effect of 60Co-γ Irradiation Sterilization Technology on the Chemical Composition of Saffron Using UPLC and UPLC/Q-TOF-MS

To evaluate the effect of ⁶⁰Co-γ irradiation sterilization technology on the chemical composition of saffron, we collected 10 batches of saffron samples and treated them with different irradiation doses. UPLC characteristic chromatogram showed that there was no significant effect of irradiation on 13 common peak areas. The results of cluster analysis and principal component analysis showed that there were no differences in the chemical composition in nonirradiated and irradiated samples. UPLC/Q-TOF-MS identified 40 characteristic components of saffron, and the results showed that all of these were detected in the saffron samples both with and without irradiation. Irradiation doses at or below 10 kGy had no significant effect on the chemical components of saffron. This provides a sound basis for the use of ⁶⁰Co-γ ray irradiation sterilization technology during the preparation of original powder saffron as a medicinal herb, for the effective destruction of mycotoxin contamination.

Metabolic profiling analysis of Siraitia grosvenorii revealed different characteristics of green fruit and saccharified yellow fruit

Siraitia grosvenorii is an economic and medicinal plant, its fruit is considered to be good to health for its diverse bioactive ingredients. However, the clarification of chemical composition and their changes after saccharification procedure are not well performed. In present study, a metabolomics method based on ultra-high-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry was developed for metabolic profiling acquisition of Siraitia grosvenorii extract. Furthermore, information dependent analysis (IDA) combined with self-constructed LC-MS/MS identification system for metabolites were employed to identify primary and secondary metabolites in Siraitia grosvenorii. A total of 126 metabolites were identified or tentatively identified. The obvious differences of metabolic profiling between green fruit and saccharified yellow fruit were observed, and metabolites showed their own distribution characteristics in peel, flesh and seed. The majority of the nutrients and effective components were more distributed in flesh and peel, and saccharification was conducive to accumulation of sweet glycosides. This study not only expanded metabolite composition information of Siraitia grosvenorii, but also specified distribution characteristics of identified metabolites.

Quantitative Analysis in Combination with Fingerprint Technology and Chemometric Analysis Applied for Evaluating Six Species of Wild Paris Using UHPLC-UV-MS

A fast method was developed by ultra high performance liquid chromatography (UHPLC) for simultaneous determination of polyphyllin I and polyphyllin II. Chemometric analyses including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) based on UHPLC chromatography were used to evaluate 38 batches from six species of Paris. Variable importance of projection was applied to select important peaks. Meanwhile, similarity analysis of UHPLC fingerprint was used to evaluate the sample of Paris polyphylla yunnanensis (PPY) and P. axialis (PA). The results indicated that the total content of saponins in PPY and PA collected from Baoshan City of Yunnan Province above 8.07 mg/g was stronger than that from other areas of the rest of species. PLS-DA showed better performance than PCA with regard to classifying the samples. Retention time during 20-27 minutes of UHPLC was screened as significant peak for distinguishing Paris of different species and original geography. All of PPY and PA with similarity value were more than 0.80. It indicated that quantitative analysis combined with chemometric and similarity analyses could evaluate the different species of Paris effectively and comprehensively.