Phospholipid removal combined with a semi-automated 96-well SPE application for determination of budesonide in human plasma with LC–MS/MS

An effective pretreatment technique based on multi-walled carbon nanotubes to reduce the matrix effect in plasma samples analyzed by a new type probe electrospray ionization method

The quantitative analysis of drug plasma samples plays an important role in the drug development and drug clinical use. Our research team developed a new electrospray ion source-Micro probe electrospray ionization (μPESI) in the early stage, which was combined with mass spectrometry (μPESI-MS/MS) showing good qualitative and quantitative analysis performance. However, matrix effect severely interfered the sensitivity in μPESI-MS/MS analysis. To solve this problem, we recently developed a Solid-phase purification method based on multi-walled carbon nanotubes (MWCNTs), which was used for removing matrix interfering substances (especially phospholipid compounds) in the preparation of plasma samples, so as to reduce the matrix effect. In this study, aripiprazole (APZ), carbamazepine (CBZ) and omeprazole (OME) were used as representative analytes, the quantitative analysis related to the plasma samples spiked with the analytes above and the mechanism of the MWCNTs to reduce matrix effect were both investigated. Compared with the ordinary protein precipitation, MWCNTs could reduced the matrix effect for several to dozens of times, which resulting from the removement of phospholipid compounds from the plasma samples by MWCNTs in the selective adsorption manner. We further validated the linearity, precision and accuracy of this pretreatment technique by the μPESI-MS/MS method. These parameters all met the requirements of FDA guidelines. It was showed that MWCNTs have a good application prospect in the drug quantitative analysis of plasma samples using the μPESI-ESI-MS/MS method.

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。

A sensitive and high-throughput LC-ESI-MS/MS method to detect budesonide in human plasma: application to an evaluation of pharmacokinetics of budesonide intranasal formulations with and without charcoal-block in healthy volunteers

Budesonide is one of the intranasal corticosteroids, referred as first-line therapy for allergic rhinitis. Its determination is a challenging task due to its extremely low plasma levels, which limits the progress in the investigation of pharmacokinetics and quality control of preparations. In this study, a sensitive and high-throughput method to determine budesonide in human plasma using budesonide-d8 as the internal standard was developed and validated. A small volume of plasma sample (0.2 mL) was diluted with 0.2 mL water, followed by a solid-phase extraction using Cleanert PEP-2 products. Extracted samples were analyzed by liquid chromatography coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Chromatographic separation of analytes was performed on an InertSustain AQ-C18 HP column (3 µm, 2.1 × 50 mm) under the reversed-phase condition with gradient elution. With the assay, linear calibration curves were obtained over the concentration range of 10-1200 pg/mL for budesonide, with considerable extraction recoveries (84.7-89.4%), and negligible matrix effects (<4.1). Moreover, the newly developed method was successfully applied to the evaluation of pharmacokinetics of two budesonide intranasal formulations with and without charcoal block in healthy volunteers.

Microextraction and Chromatographic Analysis of Budesonide Epimers in Exhaled Breath Condensate

Background:

Analysis of drug concentrations in biological fluids is required in clinical sciences for various purposes. Among other biological samples, exhaled breath condensate (EBC) is a potential sample for follow up of drug concentrations.

Methods:

A dispersive liquid-liquid microextraction (DLLME) procedure followed by a validated liquid chromatography method was employed for the determination of budesonide (BDS) in EBC samples collected using a homemade setup. EBC is a non-invasive biological sample with possible applications for monitoring drug concentrations. The proposed analytical method is validated according to the FDA guidelines using EBC-spiked samples. Its applicability is tested on EBC samples collected from healthy volunteers receiving a single puff of BDS.

Results:

The best DLLME conditions involved the use of methanol (1 mL) as a disperser solvent, chloroform (200 μL) as an extraction solvent, and centrifugation rate of 3500 rpm for 5 minutes. The method was validated over a concentration range of 21-210 μg·L-1 in EBC. Inter- and intra-day precisions were less than 10% where the acceptable levels are less than 20%. The validated method was successfully applied for the determination of BDS in EBC samples.

Conclusion:

The findings of this study indicate that the developed method can be used for the extraction and quantification of BDS in EBC samples using a low cost method.

Determination of Budesonide and Sulfasalazine in Water and Wastewater Samples Using DLLME-SFO-HPLC-UV Method

Dispersive liquid–liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) was applied to isolate budesonide (BUD) and sulfasalazine (SULF) from aqueous samples. The effects of different parameters on the efficiency on the extraction such as type of extrahent and dispersive solvent, ionic strength, pH of sample, and centrifugation time were investigated. Moreover, the influence of foreign substances on a studied process was tested. The calibration curves were recorded. The linearity ranges for BUD and SULF were 0.022–8.611 µg mL−1 and 0.020–7.968 µg mL−1 with the limit of detection (LOD) 0.011 µg mL−1 and 0.012 µg mL−1, respectively. The enrichment factors (EF) for two analytes were high: for BUD it was 145.7 and for SULF, 119.5. The elaborated procedure was applied for HPLC-UV determination of these analytes in water and wastewater samples.

Development and validation of an assay for quantifying budesonide in dried blood spots collected from extremely low gestational age neonates

Budesonide is a potential therapeutic option for the prevention of bronchopulmonary dysplasia in mechanically ventilated premature neonates. The dose and concentrations of budesonide that drive effective prophylaxis are unknown, due in part to the difficulty in obtaining serial blood samples from this fragile population. Of primary concern is the limited total blood volume available for collection for the purposes of a pharmacokinetic study. Dried blood spots (DBS), which require the collection of <200 μL whole blood to fill an entire card, are an attractive low-blood volume alternative to traditional venipuncture sampling. We describe a simple and sensitive method for determining budesonide concentrations in DBS using an ultra-high-performance liquid chromatography - tandem mass spectrometry assay. Budesonide was liberated from a single 6 mm punch using a basified methyl tert-butyl ether extraction procedure. The assay was determined to be accurate and precise in the dynamic range of 1 to 50 ng/mL. The validated assay was then successfully applied to DBS collected as part of a multi-center, dose-escalation study of budesonide administered in surfactant via intra-tracheal instillation to premature neonates between 23 and 28 weeks gestational age. These findings show that DBS are a useful technique for collecting pharmacokinetic samples in premature neonates and other pediatric populations.

Efficient discrimination and removal of phospholipids during electromembrane extraction from human plasma samples

Aim: For the first time, extracts obtained from human plasma samples by electromembrane extraction (EME) were investigated comprehensively with particular respect to phospholipids using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). Thhe purpose was to investigate the potential of EME for phospholipid cleanup in different EME systems. Results & discussion: No traces of phospholipids were detected in any of the acceptor solutions, whereas the model analytes were extracted with recoveries up to 50%. Thus, the EME systems tested in this work were found to be highly efficient for providing phospholipid-free extracts. Conclusion: Ultra-HPLC–MS/MS analysis of the donor solutions revealed that the phospholipids principally remained in the plasma samples. This proved that the phospholipids did not migrate in the electrical field and they were prevented from penetrating the supported liquid membrane.

High throughput solid phase microextraction: A new alternative for analysis of cellular lipidome?

A new SPME method for untargeted lipidomic study of cell line cultures was proposed for the first time. In this study the feasibility to monitor changes in lipid profile after external stimuli was demonstrated and compared to the conventional Bligh & Dyer method. The human hepatocellular carcinoma (HCC) cell line was used as a model. The obtained results provided a list of up-regulated and down-regulated lipids through a comparison between control (non-stimulated) cells versus the group of cells treated with polyunsaturated fatty acid (20:5). Use of the SPME technique yielded a list of 77 lipid species whose concentrations were recognized to be significantly different between control and treated cells, from which 63 lipids were up-regulated in treated cells. In general, the list was comparable to the peer list obtained by the Bligh & Dyer method. However, more diversity of lipid classes and subclasses such as LPC, sphingomyelins, ceramides, and prenol lipids were observed with the application of the SPME method. Method precision for the SPME approach was within the acceptable analytical range (5-18% RSD) for all detected lipids, which was advantageous over solvent extraction applied. The evaluation of ionization efficiency indicated no matrix effect for the SPME technique, while Bligh & Dyer presented significant ionization suppression for low abundant species such as LysoPC, PG, ceramides, and sphingomyelins, and ionization enhancement for high abundant phospholipids such as PE.

An integrated strategy for the rapid extraction and screening of phosphatidylcholines and lysophosphatidylcholines using semi-automatic solid phase extraction and data processing technology

This study attempts to establish a comprehensive strategy for the rapid extraction and screening of phosphatidylcholines (PCs) and lysophosphatidylcholines (LysoPCs) in biological samples using semi-automatic solid phase extraction (SPE) and data processing technology based on ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS). First, the Ostro sample preparation method (i.e., semi-automatic SPE) was compared with the Bligh-Dyer method in terms of substance coverage, reproducibility and sample preparation time. Meanwhile, the screening method for PCs and LysoPCs was built through mass range screening, mass defect filtering and diagnostic fragments filtering. Then, the Ostro sample preparation method and the aforementioned screening method were combined under optimal conditions to establish a rapid extraction and screening platform. Finally, this developed method was validated and applied to the preparation and data analysis of tissue samples. Through a systematic evaluation, this developed method was shown to provide reliable and high-throughput experimental results and was suitable for the preparation and analysis of tissue samples. Our method provides a novel strategy for the rapid extraction and analysis of functional phospholipids. In addition, this study will promote further study of phospholipids in disease research.

LC/MS-based polar metabolite profiling reveals gender differences in serum from patients with myocardial infarction

Myocardial infarction (MI), a leading cause of death worldwide, results from prolonged myocardial ischemia with necrosis of myocytes due to a blood supply obstruction to an area of the heart. Many studies have reported gender-related differences in the clinical features of MI, but the reasons for these differences remain unclear. In this study, we applied ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) and various statistical methods-such as multivariate, pathway, and correlation analyses-to identify gender-specific metabolic patterns in polar metabolites in serum from healthy individuals and patients with MI. Patients with diagnosed MI (n=68), and age- and body mass index-matched healthy individuals (n=68), were included in this study. The partial least-squares discriminant analysis (PLS-DA) model was generated from metabolic profiling data, and the score plots showed a significant gender-related difference in patients with MI. Many pathways were associated with amino acids and purines; amino acids, acylcarnitines, and purines differed significantly between male and female patients with MI. This approach could be utilized to observe gender-specific metabolic pattern differences between healthy controls and patients with MI.