Chromatographic and mass spectral characterization of budesonide and a series of structurally related corticosteroids using LC–MS

Separation of budesonide enantiomers with amylose-tris-[(<italic>S</italic>)-1-phenylethyl carbamate] chiral stationary phase and determination of its contents in pharmaceutical preparations

22R-布地奈德的药物活性比22S-布地奈德的强2~3倍,开发布地奈德对映体拆分和定量分析方法,可为其药物研发及质量控制提供重要依据。目前,主要以反相C₁₈固定相对布地奈德对映体进行拆分,而采用手性固定相对其进行拆分少有报道。通过考察固定相、流动相和柱温对布地奈德对映体拆分的影响,建立了基于直链淀粉-三[(S)-1-苯乙基氨基甲酸酯]手性固定相快速拆分和检测布地奈德对映体的高效液相色谱方法,其色谱条件如下:色谱柱为Chiralpak AS-RH色谱柱(150 mm×4.6 mm, 5.0 μm),流动相为乙腈-水(45:55, v/v),柱温40 ℃,流速1.0 mL/min,二极管阵列检测器(DAD),检测波长246 nm,进样量10 μL。在该色谱条件下,布地奈德的两个对映体得到较好拆分,22R-布地奈德和22S-布地奈德的保留时间分别6.40 min和7.77 min,分离度为4.64; 22R-布地奈德和22S-布地奈德分别在各自范围内线性关系良好,相关系数(R²)均为0.9999,检出限分别为0.05 μg/mL和0.07 μg/mL,定量限分别为0.16 μg/mL和0.20 μg/mL; 4个添加水平的样品加标回收率为102.63%~104.17%,相对标准偏差(RSD)为0.08%~0.57%(n=6)。将该方法应用于1批次4个吸入用布地奈德混悬液实际样品进行检测,22R-布地奈德和22S-布地奈德的含量分别为283.15~284.63 μg/mL和259.86~261.51 μg/mL。该方法操作简便,分析时间短,重复性好,准确度高,可用于布地奈德对映体的拆分及其制剂的质量控制。

Using thermal forced degradation approach for impurity profiling of budesonide solution-formulated metered dose inhalation with implementation of LC-QTOFMS and HPLC-UV

The impurity profile of budesonide solution-formulated metered dose inhalation using thermal forced degradation approach was studied intensively in this article. The structural identification of 10 budesonide related impurities was conducted by LC-QTOFMS, and the impurity level in the formulations of different excipients and packing materials were compared using HPLC-UV. Based on our results, the impurities were classified into three groups: (Ⅰ) process impurities, including budesonide impurity A, C and F; (Ⅱ) degradation products, including budesonide impurity E, G, D, 17-carboxylate, and 17-ketone; (Ⅲ) not only process impurities but also degradation products, including budesonide impurity I and L. Budesonide impurity D, 17-carboxylate, 17-ketone and impurity L were found to be the major degradation products of budesonide, and the reaction pathways for the generation of these impurities were speculated. The generation of budesonide impurity D, 17-carboxylate and L was found to be an aerobic oxidation process induced by Al₂O₃ on the inner surface of aluminum canisters. Furthermore, an in-depth discussion on the proposed impact of the excipients on budesonide degradation, especially on the Al₂O₃-induced oxidation process, was provided in this article.

Is zebrafish (Danio rerio) water tank model applicable for the assessment of glucocorticoids metabolism? The budesonide assessment

Knowledge of the metabolic profile is essential for doping control analysis in sport since most drugs are excreted after an elaborate biotransformation process. Currently, Zebrafish Water Tank (ZWT) model has been applied to investigate the metabolism of different doping agents. Nevertheless, the class of glucocorticoids has not been subjected to this model for metabolism studies. In the present work, budesonide (BUD) was applied as a pilot to investigate the metabolic pathways of glucocorticoids in the ZWT model. The BUD biotransformation in ZWT model was compared to the described metabolism in humans. Samples from ZWT experiments were collected after BUD administration and analyzed by Liquid Chromatography coupled to High Resolution Mass Spectrometry (LC-HRMS). Following the identification and characterization of all significant metabolites described for humans, it was observed that the ZWT was able to produce in a relevant amount the main target for doping control purposes: the 6β-hydroxy BUD. In addition, prior knowledge about the lack of butyrylcholinesterase activity in the zebrafish organism was considered for the evaluation for the formation of the 16α-hydroxy prednisolone, the most intense BUD metabolite in human urine. Biotransformation of BUD by ZWT focused on metabolites with the acetal fraction preserved, including the intermediate metabolite for the 16α-hydroxy prednisolone pathway. However,analternative metabolic pathway for the complete biotransformation of the 16α-hydroxy prednisolone intermediate was not observed, leading to the absence of the major human metabolite in the ZWT model. The findings reported in this study elucidate for the first time the application and limitations of the ZWT model to evaluate the metabolism of other glucocorticoids.

Screening for illegal addition of glucocorticoids in adulterated cosmetic products using ultra-performance liquid chromatography/tandem mass spectrometry with precursor ion scanning

RATIONALE

The screening for illegal adulteration of glucocorticoids (GCs) in cosmetics is challenging due to the vast variety of potential GCs that are present to improve the declared effects. An effective analytical method to screen illegally added GCs in cosmetics is vital to protect consumers.

METHODS

An ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method using precursor ion scanning (PIS) acquisition mode was developed to screen GCs in cosmetics. Forty-seven GCs were investigated to identify their common product ions formed by collision-induced dissociation. Cosmetic samples spiked with GCs were extracted using solid-phase extraction.

RESULTS

Four common positive product ions, m/z 121, 135, 147, and 171, were selected for PIS analysis. Limits of detection (LODs) were established for all 47 GCs. The method was validated on spiked samples to ensure its effectiveness in terms of sensitivity and selectivity. Sixty samples were analyzed. Seven GCs were detected in six samples.

CONCLUSIONS

An effective screening method using UPLC/MS/MS with PIS acquisition mode was developed and successfully applied to screen for targeted and untargeted GCs in cosmetic samples.

Solid-Phase Microextraction Fiber in Face Mask for in Vivo Sampling and Direct Mass Spectrometry Analysis of Exhaled Breath Aerosol

Molecular analysis of exhaled breath aerosol (EBA) with simple procedures represents a key step in clinical and point-of-care applications. Due to the crucial health role, a face mask now is a safety device that helps protect the wearer from breathing in hazardous particles such as bacteria and viruses in the air; thus exhaled breath is also blocked to congregate in the small space inside of the face mask. Therefore, direct sampling and analysis of trace constituents in EBA using a face mask can rapidly provide useful insights into human physiologic and pathological information. Herein, we introduce a simple approach to collect and analyze human EBA by combining a face mask with solid-phase microextraction (SPME) fiber. SPME fiber was inserted into a face mask to form SPME-in-mask that covered nose and mouth for in vivo sampling of EBA, and SPME fiber was then coupled with direct analysis in real-time mass spectrometry (DART-MS) to directly analyze the molecular compositions of EBA under ambient conditions. The applicability of SPME-in-mask was demonstrated by direct analysis of drugs and metabolites in oral and nasal EBA. The unique features of SPME-in-mask were also discussed. Our results showed that this method is enabled to analyze volatile and nonvolatile analytes in EBA and is expected to have a significant impact on human EBA analysis in clinical applications. We also hope this method will inspire biomarker screening of some respiratory diseases that usually required wearing of a face mask in daily life.

Investigation of PPCPs in wastewater treatment plants in Greece: occurrence, removal and environmental risk assessment

In the present work, an extensive study on the presence of eighteen pharmaceuticals and personal care products (PPCPs) in eight wastewater treatment plants (WWTPs) of Greece has been conducted. The study covered four sampling periods over 1-year, where samples (influents; effluents) from eight WWTPs of various cities in Greece were taken. All WWTPs investigated are equipped with conventional activated sludge treatment. A common pre-concentration step based on SPE was applied, followed by LC-UV/Vis-ESI-MS. Further confirmation of positive findings was accomplished by using LC coupled to a high resolution Orbitrap mass spectrometer. The results showed the occurrence of all target compounds in the wastewater samples with concentrations up to 96.65 μg/L. Paracetamol, caffeine, trimethoprim, sulfamethoxazole, carbamazepine, diclofenac and salicylic acid were the dominant compounds, while tolfenamic acid, fenofibrate and simvastatin were the less frequently detected compounds with concentrations in effluents below the LOQ. The removal efficiencies showed that many WWTPs were unable to effectively remove most of the PPCPs investigated. Finally, the study provides an assessment of the environmental risk posed by their presence in wastewaters by means of the risk quotient (RQ). RQs were more than unity for various compounds in the effluents expressing possible threat for the aquatic environment. Triclosan was found to be the most critical compound in terms of contribution and environmental risk, concluding that it should be seriously considered as a candidate for regulatory monitoring and prioritization on a European scale on the basis of realistic PNECs. The results of the extensive monitoring study contributed to a better insight on PPCPs in Greece and their presence in influent and effluent wastewaters. Furthermore, the unequivocal identification of two transformation products of trimethoprim in real wastewaters by using the advantages of the LTQ Orbitrap capabilities provides information that should be taken into consideration in future PPCP monitoring studies in wastewaters.

A sensitive and specific precursor ion scanning approach in liquid chromatography/electrospray ionization tandem mass spectrometry to detect methylprednisolone acetate and its metabolites in rat urine

A new, simple, sensitive and specific liquid chromatography/electrospray ionization tandem mass spectrometric (LC/ESI-MS/MS) method in precursor ion scanning (PIS) mode has been developed for the rapid detection of methylprednisolone acetate (MPA) and its metabolites in rat urine. A suitable product ion specific for methylprednisolone (MP) and MPA was selected after a fragmentation study on 20 (cortico)steroids at different collision energies (5-40 eV). Urine samples were simply treated with acetonitrile then dried in a SpeedVac system. The method was validated and compared with other PIS methods for detecting corticosteroids in human urine. It was more sensitive, with limit of detection (LOD) and lower limit of quantitation (LLOQ), respectively, of 5 and 10 ng mL(-1). The method was applied for the analysis of rat urine collected before and after (24, 48, 72 h) intra-articular (IA) injection of a marketed formulation of MPA (Depo-Medrol(R)). MS/MS acquisitions were taken at different collision energies for the precursor ions of interest, detected in PIS mode, to verify the MP-related structure. Six different metabolites were detected in rat urine, and their chemical structures were assigned with a computational study.

Quantitative measurements of corticosteroids in ex vivo samples using on-line SPE-LC/MS/MS

Abnormal elevation of 11beta-HSD1 activities in tissues, such as fat and brain, may contribute to the development of the abdominal obesity and Alzheimer disease, and the inhibition of 11beta-HSD1 might be beneficial to the management of these diseases. To assess the effects of pharmacologic inhibitors of 11beta-HSD1, we developed a fast LC/MS/MS method to quantify corticosteroids in minced tissue samples in the presence of 11beta-HSD substrates. The novel on-line SPE-LC/MS/MS method was developed with dual binary gradient and a throughput of 4.5 min/sample. A total of six corticosteroids (cortisol, cortisone, corticosterone, dehydrocorticosterone, dexamethasone, and dehydrodexamethasone) were studied. The lower limit of quantitation from 0.40 to 11.4 fmol and 4.5 orders magnitude of dynamic range were obtained for these six compounds. Three novel enzymatic bi-products, all isomers of cortisol, were observed in the liver or fat samples. Two of them were identified by matching the HPLC retention times and MS/MS spectra with authentic compounds. The potential interferences of these isomers and their removal are discussed.