Formic Acid In Water Research Articles

Effect of Sophocarpine on the Pharmacokinetics of Umbralisib in Rat Plasma Using a Novel UPLC-MS/MS Method.

Umbralisib is a dual inhibitor of phosphatidylinositol 3-kinase delta (PI3Kδ) and casein kinase 1 epsilon (CK1ε) for treating marginal zone lymphoma (MZL) and follicular lymphoma (FL). This study aimed to develop a fast and stable ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for quantitative analysis of umbralisib in rat plasma and its application for evaluating the effect of sophocarpine on the pharmacokinetics of umbralisib. A direct protein preparation with acetonitrile was used to deal with rat plasma. Umbralisib and duvelisib (internal standard, IS) were isolated on a Waters Acquity UPLC BEH C18 column with mobile phase consisted of acetonitrile and 0.1% formic acid in water. The linear range was from 0.5 to 1,000 ng/ml. Both of the precision (RSD%) and accuracy (RE%) were less than 15% in a permissible range. The mean recovery and matrix effect of umbralisib were 86.3–96.2% and 97.8–112.0%, respectively. When umbralisib was combined with sophocarpine, AUC0→∞ of umbralisib was significantly reduced to 2462.799 ± 535.736 ng/ml•h from 5416.665 ± 1,451.846 ng/ml•h, and Cmax also was markedly diminished. Moreover, CLz/F was increased more than two times. This developed, optimized and technical UPLC-MS/MS method was extremely suitable for detecting the concentrations of umbralisib in rat plasma after an oral administration, and sophocarpine significantly changed the pharmacokinetics of umbralisib in rats. This obvious pharmacokinetic changes indicates that there seems to exist herb-drug interaction between sophocarpine and umbralisib.

Estimation of minoxidil in human plasma using UHPLC-MS/MS and its application in pharmacokinetic study

Measurement of drug concentration in biological matrices (such as serum, plasma, blood, urine, and saliva) is important to determine Bioavailability (BA) and/or Bioequivalence (BE) of a drug product which are required during the drug product development and approval process to support applications for new active substances (INDs, NDAs) and generic (ANDAs) drug products to make critical decisions on safety and efficacy. Because of their vital role, bioanalytical methods should be well-characterized, fully validated and documented to yield reliable results. In present work, a simple, specific, high throughput, accurate and sensitive UHPLC–MS/MS method has been developed and validated for quantification of Minoxidil in human plasma. The analyte and the internal standard were extracted from plasma by Liquid-Liquid Extraction using ethyl acetate. The chromatographic separation was achieved on Thermo Hypersil Gold column (4.6x50mm, 5μm) using acetonitrile-0.1% formic acid in water (60:40, v/v) at a flow rate of 0.400 ml/min. Detection by turbospray positive ionization mass spectrometry in the multiple reaction monitoring mode with a mass transition ion-pair of m/z 210.152 → 163.965 (Minoxidil) and m/z 220.267 → 169.089 (Internal Standard-Minoxidil D10) was found to be linear over the concentration range of 1.280 to 151.075 ng/ml. The method was fully validated as per USFDA guidelines and the results were within regulatory limits. The inter and intra-day precision ranged from 5.42 to 9.27% and 2.55–9.42% respectively. The inter and intra-day accuracy ranged from 89.2 to 98.9% and 102–105% respectively. The method was successfully applied to a BE study involving human volunteers.

A validated LC-MS/MS method for simultaneous quantification of simvastatin and simvastatin acid in beagle plasma: Application to an absolute bioavailability study.

A highly sensitive LC-MS/MS method for simultaneous detection of both simvastatin (SV) and simvastatin acid (SVA) in beagle plasma was developed and successfully applied to an absolute bioavailability study. Lovastatin (LV) was used as internal standard (IS). The analysis was performed using electrospray ionization and selective reaction monitoring in positive mode at m/z 441.0 → 325.0 for SV, 459.0 → 343.0 for SVA and 427.0 → 325.0 for the IS, respectively. The assay procedure involved a simple liquid-liquid extraction of SV, SVA and LV from beagle plasma into methyl tert-butyl ether. Separation of SV, SVA and the IS was achieved on a Shim-pack VP-ODS column (150 × 2.0mm, 5μm) with a binary gradient solvent system of 0.1% formic acid in water and methanol (15:85, v/v) as the mobile phase. The method was validated over the range of 0.25-500 ng/ml for SV (r2 ≥ 0.9923) and 0.24-481.23 ng/ml for SVA (r2 ≥ 0.9987). The results of method validation for accuracy, precision, extraction recovery, matrix effect and stability were within the acceptance criteria. The values of absolute bioavailability of SV and SVA in beagles were 2.97 and 25.40%, respectively. It is the first study developed for the measurement of absolute bioavailability of SV and SVA acid in beagles.

Pharmacokinetic and brain distribution study of an anti-glioblastoma agent in mice by HPLC-MS/MS.

Previously compound I showed great anti-glioblastoma activity without toxicity in a mouse xenograft study. In this study, a sensitive and rapid high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated to investigate the pharmacokinetics and brain distribution of compound I in mice. The protein precipitation method was applied to extract the compound from mouse plasma and brain homogenates, and it was then separated using a Kinetex C18 column with a mobile phase consisting of acetonitrile-0.1% formic acid water (50:50, v/v). The analytes were detected with multiple reaction monitoring for the quantitative response of the compounds. The inter- and intra-day precisions were <8.29 and 3.85%, respectively, and the accuracy range was within ±7.33%. The method was successfully applied to evaluate the pharmacokinetics of compound I in mouse plasma and brain tissue. The peak concentration in plasma was achieved within 1h. The apparent elimination half-life was 4.06 h. The peak concentration of compound I in brain tissue was 0.88 μg/g. The results indicated that compound I was rapidly distributed and could cross the blood-brain barrier. The pharmacokinetic profile summarized provides valuable information for the further investigation of compound I as a potential anti-glioblastoma agent.

Manganese oxide as an alternative to vanadium-based catalysts for effective conversion of glucose to formic acid in water

MnOx was used as a vanadium-free catalyst for conversion of glucose to formic acid in water with 81% yield in which α-scission (C1–C2 bond cleavage) with arabinose being an intermediate was found to be the major conversion pathway.

DETERMINAÇÃO DE ETIL-GLICURONÍDEO E ETIL-SULFATO EM SANGUE POR UPLC-MS/MS: APLICAÇÃO CLÍNICA EM VÍTIMAS DE TRAUMA

DETERMINATION OF ETHYL-GLUCURONIDE AND ETHYL-SULFATE IN BLOOD BY UPLC-MS/MS: CLINICAL APPLICATION IN TRAUMA VICTIMS. We developed a UPLC-MS/MS method for the quantification of the ethanol metabolites ethyl-glucuronide (EtG) and ethyl-sulfate (EtS) in blood samples. Sample preparation was a protein precipitation with acetonitrile 0.1% formic acid containing internal standards (IS) 0.5 µg mL-1 EtG-D5 and EtS-D5. Chromatographic separation was performed in a fluoro-phenyl column, mobile phases were 0.1% formic acid in water (A) and acetonitrile (B) in gradient elution from 5% B to 70% B, with 10 min run time. Ionization was performed with electrospray source at 550 °C in negative mode, quantification mass transitions of m/z EtG 221- 75, EtS 125- 80.1, EtS-D5 130- 79.9, and EtG-D5 226- 75.1. The method was linear from 0.1 to 18 µg mL-1 for EtG and 0.02 to 6 µg mL-1 for EtS, specific, with no interfering peaks during the blank samples analyses. The method was precise and accurate, the matrix effect was compensated with the IS (-12% a + 6.1%). EtG and EtS were analyzed in 28 blood samples from trauma patients with positive alcoholaemia. The concentrations of EtG and EtS ranged from 0.25 to 14.11 µg mL-1 and 0.13 to 5.53 µg mL-1, with high correlation with ethanol concentrations, r=0.739 and r=0.817 (p &lt;0,001), respectively

Characterization of Loratadine API and Simultaneous Quantification of Seven Potential Genotoxic Nitrosamine Impurities in Single Method by LC-MS/MS in Loratadine API and its Dosage Forms

Active pharmaceutical ingredients (APIs) of loratadine were characterized using spectroscopic methods such as infrared spectroscopy, mass spectroscopy, differential scanning calorimetry (DSC), 1H NMR, 2D nuclear magnetic resonance (2D-NMR) and 13C NMR. Nitrosamine impurities, which are considered under concern cohort according to the S2 FDA and ICH M7 guidelines, are highly genotoxic and their trace-level quantity must be controlled in drugs for safe human consumption. In this study, an ultra-sensitive, rapid and simple LC-MS/MS technique is developed to detect seven nitrosamine impurities (N-nitroso dimethylamine (NDMA), N-nitroso-N-methyl-4-aminobutyric acid (NMBA), N-nitroso diethylamine (NDEA), N-nitroso ethyl isopropylamine (NEIPA), N-nitroso diisopropylamino (NDIPA), N-nitroso methyl phenylamine (NMPA) and N-nitroso dibutylamine (NDBA) in loratadine drug) with potential genotoxicity. Chromatographic separation was attained by employing the Zorbax SB C18 of 150 × 3 mm and a column of 3.5 μ with 0.1% formic acid in water and methanol as mobile phases A and B, respectively. At the total run time of 20 min, the flow rate was 0.3 mL/min in the gradient mode of elution. Through multiple reaction monitoring (MRM), all the seven nitrosamine impurities were successfully ionized and then quantified in the positive mode of atmospheric pressure chemical ionization (APCI). The method was validated according to the ICH guidelines by estimating quantification and detection limits. For all the seven nitrosamine impurities, the method provided excellent S/N ratios with a high linearity range of 0.8-5.30 ppm for loratadine sample concentrations with a regression coefficient of &gt;0.99. The recovery for the method was established with a protocol of three-step sample preparation and was satisfactory within 15-115%. The proposed method can be employed for the routine detection of nitrosamines in loratadine APIs and its doses.

Stability indicating reverse phase (RP)-high-performance liquid chromatography method development and validation for the simultaneous estimation of olanzapine and samidorphan in bulk and tablets

Background Patients with schizophrenia are given a combination tablet combining olanzapine (OLA), an atypical antipsychotic and samidorphan (SAM), an opioid receptor antagonist. Objectives In bulk and tablet dosage forms, a stability-indicating reverse phase (RP)-high-performance liquid chromatography technique for the simultaneous determination of OLA and SAM has been developed and validated. Materials and methods The chromatographic analysis was performed using an isocratic mobile phase of 0.1% formic acid in water : methanol : acetonitrile (10 : 40 : 50, v/v) at a flow rate of 0.8 ml/min, and the eluents were monitored at an isosbestic point of 285 nm. Results and conclusion The suggested method’s specificity, precision, accuracy, linearity, and robustness were all validated according as per International Conference on Harmonization guidelines. The method’s stability was validated by forced degradation experiments. Retention times for OLA and SAM were 2.85 and 4.79 min, respectively. The method was found to be precise and accurate. SAM linearity was found to be between 14.0 and 45.0 µg/ml, whereas OLA linearity was found to be between 22.5 and 67.5 µg/ml. The limit of detection (LOD) and limit of quantification (LOQ) of OLA were 2.65 and 8.85 µg/ml, respectively, whereas the LOD and LOQ of SAM were 8.12 and 27.06 µg/ml, respectively. As a result, the suggested high-performance liquid chromatography method for the quantification of OLA and SAM was reliable, repeatable, accurate, and sensitive.

Efficient hydrogenation of CO2 to formic acid in water without consumption of a base

CO2 hydrogenation to formic acid was achieved without consumption of a base and a turnover number of up to 364 249 was obtained. HCOOH is isolatable and the catalyst–base system is easily recycled.

Dimension-Enhanced Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry Combined with Intelligent Peak Annotation for the Rapid Characterization of the Multiple Components from Seeds of Descurainia sophia

The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components. The seeds of Descurainia sophia (SDS) are utilized in China as a cough and asthma relieving agent. Herein, a dimension-enhanced integral approach, by combining ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (UHPLC/IM-QTOF-MS) and intelligent peak annotation, was developed to rapidly characterize the multicomponents from SDS. Good chromatographic separation was achieved within 38 min on a UPLC CSH C18 (2.1 × 100 mm, 1.7 μm) column which was eluted by 0.1% formic acid in water (water phase) and acetonitrile (organic phase). Collision-induced dissociation-MS2 data were acquired by the data-independent high-definition MSE (HDMSE) in both the negative and positive electrospray ionization modes. A major components knockout strategy was applied to improve the characterization of those minor ingredients by enhancing the injection volume. Moreover, a self-built chemistry library was established, which could be matched by the UNIFI software enabling automatic peak annotation of the obtained HDMSE data. As a result of applying the intelligent peak annotation workflows and further confirmation process, a total of 53 compounds were identified or tentatively characterized from the SDS, including 29 flavonoids, one uridine derivative, four glucosides, one lignin, one phenolic compound, and 17 others. Notably, four-dimensional information related to the structure (e.g., retention time, collision cross section, MS1 and MS2 data) was obtained for each component by the developed integral approach, and the results would greatly benefit the quality control of SDS.

Determination of Trans-loxoprofen-alcohol Tromethamine in Pregnant SD Rats by a Validated LC-MS/MS Method：Application to a Toxicokinetics and Tissue Distribution Study

Background: As an anti-inflammatory prodrug, loxoprofen is metabolized into transloprofenol to treat diseases related to pain and inflammation. Although loxoprofen has fewer adverse effects than other NSAIDs, the safety of its usage during pregnancy remains unclear and needs to be considered. Fortunately, the toxicokinetics and tissue distribution study of transloxoprofen- alcohol in pregnant rats can resolve the problem. Objective: The purpose of this study is to establish a simple, sensitive, and effective LC-MS/MS analysis method for determining the concentration of trans-loxoprofen alcohol in plasma and tissues. Methods: The analytic samples were precipitated by methanol in one step and separated using a reverse-phase Poroshell 120 EC-C18 column (4.6 mm×50 mm; 2.7 μm). And the mobile gradient phase at a flow rate of 0.6 mL/min was composed of acetonitrile and 0.1% formic acid in water. The quantitative detection was achieved by multiple-reaction monitoring mode with a positive electrospray ionization source, transitional ion pairs of m/z 265.9&gt;184.8 for trans-loxoprofenalcohol, and 268.8&gt;187.9 for rac-trans-loxoprofen-D3 alcohol (Internal standard). Results: A good linearity of calibration curves for plasma and tissues was observed in the concentration range from 5.0 to 5000 ng/mL, and the lower limit of quantification was detected at 5.0 ng/mL. The intra-day and inter-day precision in plasma and tissues were within 8.94% and 7.26%, respectively. The mean extraction recovery and matrix effects in plasma and tissues were in the range of 89.08~109.27% and 89.00~106.80%, respectively. Precision of stability in plasma and tissues was within 8.91% and 7.08%, respectively. Conclusion: Complying with the requirements of bioanalytical guidelines by validation, this method was successfully adopted to the toxicokinetics and tissue distribution study after intravenously administrated trans-loxoprofen-alcohol into pregnant SD rats.

Forced degradation studies and structural characterization of related substances of bisoprolol fumarate in finished drug product using LC-UV-MS/MS

Methods for determination of bisoprolol and related substances mostly use UV detection and a phosphate buffer and are not suitable for MS detection. In this study, LC?UV?MS/MS for separation and characterization of bisoprolol related substances was developed, validated and applied for studying the degradation products of bisoprolol when exposed to hydrolytic stress, heat and light. The method uses a C18 column, formic acid in water and acetonitrile as mobile phases, gradient elution and UV and MS detection. Forced degradation revealed that acid hydrolysis produces the most intensive transformation of bisoprolol to its impurity A, along with impurities L and D. Alkaline hydrolysis produced impurities A, L, Q, G and K; oxidative and thermal degradation produced impurities A, L and K, while photodegradation produced impurities A, L, G and K, all characterized by their mass spectral data. The developed method using two detection systems was demonstrated as efficient since mass spectra allowed identification of the related substances of bisoprolol and quantification was possible using absorbance measurements at 270 nm. The obtained results will fill in the lack of data on the fragmentation patterns of bisoprolol and related substances that could be used by researchers and practitioners in research and quality control laboratories.

Rapid Profiling and Characterization of the Multicomponents from the Root and Rhizome of Salvia miltiorrhiza by Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry in Combination with Computational Peak Annotation Workflows

Herbal components characterization represents a challenging task because of the co-existing of multiple classes of naturally occurring compounds with wide spans of polarity, molecular mass, and the ubiquitous isomerism. The root and rhizome of Salvia miltiorrhiza have been utilized as a reputable traditional Chinese medicine Salviae Miltiorrhizae Radix et Rhizoma (Dan-Shen) in the treatment of cardiovascular disease. Herein, a dimension-enhanced ultra-high performance liquid chromatography/ion mobility/quadrupole time-of-flight mass spectrometry approach in combination with intelligent peak annotation workflows was established aimed to rapidly characterize the multicomponents from S. miltiorrhiza. Due to the sufficient optimization, satisfactory chromatography separation was enabled on an HSS T3 column within 33 min using 0.1% formic acid in water (A) and acetonitrile (B) as the mobile phase, while the data-independent HDMSE in both the negative and positive electrospray ionization modes was utilized for the high-coverage MS2 data acquisition. Streamlined automatic peak annotation by searching an in-house library (recording 198 known compounds) followed by the subsequent confirming steps (e.g., comparison with the reference compounds, fragmentation pathways analysis, and retention behavior comparison, etc.), allowed us to identify or tentatively characterize a total of 86 components (including 50 terpenoids, 21 phenolic acids, and 15 others) from S. miltiorrhiza. Importantly, three-dimensional structure information, such as the retention time, MS1 and MS2 data, and collision cross section (CCS), was provided, which can facilitate the more reliable characterization of herbal components.

HPLC quantitative analysis of protocatechuic acid contents in 11 Phellinus mushroom species collected in Thailand

Phellinus mushrooms have been traditionally used for various medicinal purposes. Protocatechuic acid, which was previously reported to be a component in some Phellinus mushrooms, has some pharmacological effects. This study aimed to validate a HPLC method for the quantitative analysis of the protocatechuic acid contents in the extracts from different Phellinus mushroom species collected in Thailand. HPLC was carried out using a C18 column and the gradient mobile phases of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. Method validation was performed to assure the linearity, accuracy, precision, limit of detection and limit of quantitation of the analytical method. The linearity range of protocatechuic acid was 1 - 10 µg/ml. The average recovery was 104.16%. The method was shown to be precise with the RSD of repeatability and intermediate precision at less than 3%. The protocatechuic contents in 11 Phellinus mushrooms were in the range of less than 0.0099 - 0.4121 %w/w of the extract. The developed HPLC method was reliable and suitable for the quantitative analysis of protocatechuic acid content in Phellinus mushrooms.

Rapid screening and identification of 62 kinds of illegally added traditional Chinese medicine in food by high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry

建立了高效液相色谱-四极杆-飞行时间质谱快速筛查鉴别食品中非法添加的62种中药材的方法。依据卫生部关于进一步规范保健食品原料管理的通知(卫法监发[2002]51号)中可用于保健食品的物品名单,确定食品中可能非法添加的62种中药材原料清单,再从62种中药材中筛选其特征组分,获得不同中药材对应的特征组分清单。62种对照药材经甲醇超声提取后,于Thermo Accucore aQ色谱柱(150 mm×2.1 mm, 2.6 μm)上分离,在电喷雾正负离子扫描模式下,分别以0.1%(v/v)甲酸水溶液-乙腈和水-乙腈为流动相梯度洗脱,进行一级质谱和二级质谱全扫描检测,采用Library View软件建立不同中药材对应的特征组分的一级精确质量数据库和二级碎片质谱库。样品同法处理后上样分析,采用Peak View软件将样品高分辨数据与自建数据库中的质谱图、精确分子离子质量数、碎片离子质量数、保留时间等相关参数进行快速筛查鉴别分析。该工作通过建立“中药材-特征组分”对应清单,构建了食品中易非法添加的62种中药材中共388种特征组分的高分辨质谱库,每种中药材包括5~10种特征组分,通过对实际食品样品配制酒、代用茶及饮料进行筛查分析,1批次配制酒样品与淫羊藿中药材的7种特征组分匹配一致,推断该配制酒样品中加入了淫羊藿中药材。该法可实现无标准品情况下中药材的定性筛查,具有高通量、准确、简便、快捷的特点,解决了食品中非法添加中药材难以识别和确证的难题,可以实现食品中非法添加中药材的快速筛查鉴别分析。

A Quantitative LC-MS/MS Method for the Simultaneous Determination of the Presence of R-α-lipoic Acid and S-α-lipoic Acid After Protein Precipitation in Rat Plasma and its Application in a Toxicokinetic Study

Background: Lipoic acid is the only known chiral antioxidant that is both lipidsoluble and water-soluble. It is often used as a treatment for peripheral polyneuropathy caused by diabetes, alcohol, and chemicals. However, only a few long-term toxicological studies have been conducted on R-α-lipoic acid, which is a bioactive ingredient in lipoic acid. Objective: In this study, a simple, efficient, sensitive and stable LC-MS/MS method was used to determine RLA in rats, using deu-lipoic acid as an internal standard. Method: The samples to be detected were plasma samples treated with protein precipitation and the simultaneous determination of the presence of R-α-lipoic acid and S-α-lipoic acid was conducted using LC-MS/MS. An isocratic elution program with a mobile phase composed of acetonitrile and 0.1% formic acid water solution (52/48) used for chromatographic separation was set up using a CHIRALPAK® IE C18 (250 mm × 4.6 mm, 5 μm) column with a flow rate of 0.9 mL/min. A negative electrospray ionization source was chosen, and the multiple monitoring (MRM) mode was applied. Results: R-α-lipoic acid and S-α-lipoic acid both were found to be present at a linear range of 5- 5000 ng/mL. The plasma samples were stable under various storage conditions and temperatures. The toxicokinetics study indicated that there were gender differences and that R-α-lipoic acid showed bioaccumulative toxicity after long-term daily administration. In addition, R-α-lipoic acid and S-α-lipoic acid were not converted into each other in the rats. Conclusions: The method established was successfully used for the long-term toxicokinetic study of R-α-lipoic acid administered to rats through caudal vein injection. The toxicokinetics results indicated the presence of gender differences and the toxic accumulation of R-α-lipoic acid. The two enantiomers were not converted into each other in the rats.

Evaluation of aloins, pH and moisture in aloe leaf gel-based personal care products.

Some easily applicable analytical methods were explored to evaluate the quality of personal care products containing aloe leaf gel. Aloins should be absent in these products in view of their side effects. To check this, liquid chromatography (LC) was applied. The LC method used a C18monolithic column combined with gradient elution and ultraviolet (UV) detection. The mobile phase consisted of a mixture of 0.1% formic acid in water (A) and 0.1% formic acid in acetonitrile (B). The method was validated with respect to specificity, linearity, precision and accuracy. Next, it was practically applied for the analysis of commercial samples. In addition, the pH and moisture content were determined. The LC results indicated that aloins were detected in 25% of the analysed commercial samples. Further, it turned out that 42% of the test samples were found to be in the basic pH range and 33% of them contained excessive moisture. Proper quality control and adequate labelling of aloe leaf gel-based cosmetics are mandatory to avoid side effects.

QbD-Based Development and Validation of Novel Stability-Indicating Method for the Assay and Dissolution of Garenoxacin in Garenoxacin Tablets.

Garenoxacin mesylate is a novel des-fluoro(6) quinolone, approved and marketed for human use in Japan under the name Geninax. In this current work, a simple and stability-indicating method for the assay and dissolution of garenoxacin in garenoxacin tablets 200 mg was performed. New method developed for the particle size measurement of Garenoxacin mesylate Active Pharmaceutical Ingredient using Malvern 2000. A quality by design (QbD)-based stability-indicating assay method was developed using 0.1% (v/v) formic acid in water and methanol (70:30). Using a photodiode array detector the peak purity of the garenoxacin peak for all degradation samples was studied. The biopharmaceutical classification system (BCS) solubility of garenoxacin mesylate active pharmaceutical ingredient (API) was studied by a modified shake flask method. A dissolution test method was developed using 0.1 N hydrochloric acid as the medium, United State Pharmacopoeia apparatus-II (paddle), revolution per minute (rpm) 50, temperature 37 ± 0.5°C and time 30 min. Liquid paraffin was used as the dispersant in the particle size measurement of garenoxacin mesylate API using the Malvern Mastersizer-wet method. The QbD-based RP-HPLC method was stability-indicating, simple, precise, and accurate. The assay method was linear over 12.5 to 75 µg/mL at the detection wavelength of 280 nm. A UV-based method was developed and validated for the dissolution of garenoxacin 200 mg tablets and the method was found to be linear over 2.9 to 34.2 µg/mL at 280 nm. Based on data, the dissolution tolerance for garenoxacin 200 mg tablets was proposed as Q not less than 80% at time 30 min (% drug released with respect to label claim (Q). The effect of garenoxacin mesylate API particle size in the tablet dosage form was studied using particles of 92 µm and 220 µm [90% of the total particles are smaller than this size (D90)] and it was found that there was no impact on the in vitro dissolution profile. The reported stability-indicating assay and dissolution test methods can be used in regular QC testing of garenoxacin 200 mg tablets. The Malvern particle size wet dispersion measurement method developed and validated for garenoxacin mesylate API is simple and robust. A QbD based RP-HPLC method (using Design Expert Software version 11) was developed and studied peak purity of Garenoxacin peak using Photo Diode Array detector (for all degradation samples, control sample and standard solution) and the same method is validated following USP and ICH guidelines.LC-MS compatible volatile buffer solution is used in the preparation of the mobile phase for the novel stability-indicating RP-HPLC assay method.

Liquid chromatography-mass spectrometric methods for trace quantification of potential genotoxic impurities in ivacaftor and lumacaftor

The objective of the current study was to develop and validate the sensitive LC-MS methods for trace analysis of genotoxic impurities in Ivacaftor and Lumacaftor. The first method is for the trace analysis of 2,4-di-tert-butyl-5-nitrophenol in ivacaftor and the second method is for the trace analysis of 1-(2,2-difluoro-1,3-benzodioxol-5yl)-cyclopropane carboxylic acid and 3-carboxyphenyl boronic acid in lumacaftor.High pure analytical grade solvents and reagents were used for this study. The chromatographic separation was performed on Luna C18 (250×4.6mm, 5.0μm) at a column temperature of 25°C using eluent consisting of acetonitrile and 0.1% v/v formic acid in water in a gradient elution mode. The eluent was run at a flow of 1.0mL/min and injection volume of 20μL.The linearity, precision and accuracy of the developed methods was validated over the concentration range of 0.35-15.0ppm for 2,4-di-tert-butyl-5-nitrophenol, 0.30-15.0ppm for 1-(2,2-difluoro-1,3-benzodioxol-5yl)-cyclopropane carboxylic acid and 0.23-15.0ppm for 3-carboxyphenyl boronic acid. In both methods, interference was not observed at the retention time of analyte peaks. All the analytes were found to be stable in solution for a period of 48h.The proposed methods are reliable, sensitive, precise, accurate, and robust for the trace level quantification of genotoxic impurities in Ivacaftor and Lumacaftor. These methods can be successfully implemented in the quality control lab for routine analysis.

Qualitative and quantitative analysis of alkaloids in Eurycoma longifolia by HPLC-Q-TOF-MS combined with UPLC-QQQ-MS/MS

A sensitive and efficient method was established and validated for qualitative and quantitative analysis of total alkaloids from the extract of Eurycoma longifolia by high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(HPLC-Q-TOF-MS) combined with ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry(UPLC-QQQ-MS/MS). The HPLC-Q-TOF-MS conditions are as follows: Welch Ultimate XB-C_(18) column(4.6 mm×250 mm, 5 μm) with acetonitrile(containing 0.1% formic acid)-0.1% formic acid in water as mobile phase for gradient elution. The UPLC-QQQ-MS/MS conditions are as below: Agilent Eclipse Plus C_(18) column(2.1 mm×50 mm, 1.8 μm) with acetonitrile(containing 0.1% formic acid) and 0.1% formic acid in water as mobile phase for gradient elution. MS data were collected by electrospray ionization in positive ion mode. According to the comparison with reference standards and the accurate masses of molecules, a total of 17 alkaloids in E. longifolia extract were identified by HPLC-Q-TOF-MS. The UPLC-QQQ-MS/MS quantitative analysis result of 3 alkaloids showed that the linear ranges of them were good(r≥0.999 7) and the overall recoveries ranged from 108.8%-110.2%, with RSDs of 2.9%-5.3%. The method is accurate, reliable, and efficient, which can comprehensively reflect the constituents and content of alkaloids in E. longifolia. The result can serve as a reference for further elucidating its therapeutic material basis and quality control.