Acquity Ultra-performance Liquid Chromatography Research Articles

Variations of Major Glucosinolates in Diverse Chinese Cabbage (Brassica rapa ssp. pekinensis) Germplasm as Analyzed by UPLC-ESI-MS/MS.

In this study, the variability of major glucosinolates in the leaf lamina of 134 Chinese cabbage accessions was investigated using Acquity ultra-performance liquid chromatography (UPLC-ESI-MS/MS). A total of twenty glucosinolates were profiled, of which glucobrassicanapin and gluconapin were identified as the predominant glucosinolates within the germplasm. These two glucosinolates had mean concentration levels above 1000.00 μmol/kg DW. Based on the principal component analysis, accessions IT186728, IT120044, IT221789, IT100417, IT278620, IT221754, and IT344740 were separated from the rest in the score plot. These accessions exhibited a higher content of total glucosinolates. Based on the VIP values, 13 compounds were identified as the most influential and responsible for variation in the germplasm. Sinigrin (r = 0.73), gluconapin (r = 0.78), glucobrassicanapin (r = 0.70), epiprogoitrin (r = 0.73), progoitrin (r = 0.74), and gluconasturtiin (r = 0.67) all exhibited a strong positive correlation with total glucosinolate at p < 0.001. This indicates that each of these compounds had a significant influence on the overall glucosinolate content of the various accessions. This study contributes valuable insights into the metabolic diversity of glucosinolates in Chinese cabbage, providing potential for breeding varieties tailored to consumer preferences and nutritional demands.

Analysis of Secondary Metabolites of Elaeagnus Angustifolia Leaves Based on UPLC-Q-TOF-MS.

The leaves of Elaeagnus angustifolia, belonging to the Elaeagnaceae Juss. family, are known for their medicinal properties for relieving cough and asthma, as well as treating dysentery and diarrhea. To establish a rapid qualitative method for the detection of secondary metabolites in leaves of Elaeagnus angustifolia, including the identification and analysis of various secondary metabolites in leaves of Elaeagnus angustifolia. Samples were separated using a Waters ACQUITY H-Class ultra-performance liquid chromatography (UPLC) system (FTN autosampler, quaternary LC pump) and ACQUITY UPLC® BEH C18 column (1.7 μm, 2.1 mm× 100 mm). The flow rate was set to 0.4 mL/min, the injection volume was 1.0 μL, and the column temperature was set to 45 °C. The mobile phase was methanol (A) with) -0.1% formic acid in water (B). Samples were analyzed by quadrupole time-of-flight mass spectrometry (Q-TOF-MS). A total of 182 different secondary metabolites were detected from 10 varieties of leaves of Elaeagnus angustifolia, including 77 flavonoids, 20 steroids, 7 alkaloids, 15 amino acids, 18 organic acids, and 45 other compound types. A method for the rapid analysis of leaves of Elaeagnus angustifolia by UPLC-Q-TOF-MS was established, and the secondary metabolites in leaves of Elaeagnus angustifolia were identified. The enrichment of secondary metabolites in leaves of different varieties of Elaeagnus angustifolia was clarified. The UPLC-Q-TOF-MS method is very fast and possesses a high degree of selectivity, precision, and sensitivity. These findings provide a reliable foundation for the development of medicinal resources derived from Elaeagnus angustifolia leaves.

Development of a Stability Indicating UPLC Method for the Determination of Tirbanibulin in Bulk and Its Pharmaceutical Dosage Form.

The primary goal of this study was to create and validate a simple, precise, sensitive, and accurate ultra-performance liquid chromatography (UPLC) method for estimating tirbanibulin in pure and dosage form. A UPLC technique was developed using a Waters Acquity UPLC Phenyl (100 x 2.1 mm, 1.7 µm) column. The developed technique was validated in accordance with the International Conference on Harmonization (ICH) guidelines. Tirbanibulin was separated chromatographically with high resolution using the mobile phase acetonitrile: buffer (30:70 v/v) at 0.5 mL/min, 5 µL injection volume, and 220 nm wavelength. The validated technique was found to be linear in the 1-15 µg/mL range. The detection and quantification limits for tirbanibulin were 0.03 and 0.1 µg/mL, respectively. The percentage relative standard deviation was less than 2%, demonstrating the precision of the developed technique. Furthermore, the recovery rate was nearly 100%, confirming the accuracy of the method. Minor modifications to the chromatographic conditions demonstrated the robustness of the method. The developed analytical method was precise, simple, reproducible, and sensitive. Consequently, it can be used to determine tirbanibulin.

Variability of Glucosinolates in Pak Choy (Brassica rapa subsp. chinensis) Germplasm.

Glucosinolates are sulfur-containing phytochemicals generally abundant in cruciferous vegetables such as pak choy. Glucosinolates participate in a range of biological activities essential for promoting a healthy human body. In this study, we aimed to elucidate glucosinolate variability present in pak choy germplasm that are under conservation at the Rural Development Administration Genebank, Jeonju, Republic of Korea. The Acquity Ultra-Performance Liquid Chromatography (UHPLC) analytical system was used in profiling the glucosinolate content in leaf samples of various accessions. We identified a total of 17 glucosinolates in the germplasm. Based on principal compoment analysis performed, three separate groups of the accessions were obtained. Group 1 contained the cultivar cheongsacholong which recorded high content of glucobrassicin (an indole), glucoerucin (aliphatic), gluconasturtiin (aromatic) and glucoberteroin (aliphatic). Group 2 consisted of six accessions, BRA77/72, Lu ling gaogengbai, 9041, Wuyueman, RP-75 and DH-10, predominatly high in aliphatic compounds including glucoiberin, glucocheirolin, and sinigrin. Group 3 comprised the majority of the accessions which were characterized by high content of glucoraphanin, epiprogoitrin, progoitrin, and glucotropaeolin. These results revealed the presence of variability among the pak choy germplasm based on their glucosinolate content, providing an excellent opprtunity for future breeding for improved glucosinolate content in the crop.

Hydrogen Peroxide Plasma Sterilization Sabotages the Efficacy of Lidocaine HCl Injection

Background: Lidocaine injection with 2% HCl as an anesthetic drug must guarantee its sterility to avoid microbial contamination. In efforts to maintain the sterile preparation of Lidocaine HCl 2% before use in hospitals, some anesthesiologists opt for re-sterilization. Objective: This study aimed to evaluate the impact of plasma sterilization using hydrogen peroxide on Lidocaine HCl levels employing a validated Ultra Performance Liquid Chromatography (UPLC) assay. Methods: The 2% Lidocaine HCl samples were separated into two groups, one undergoing re-sterilization with hydrogen peroxide and the other handled only with aseptic techniques. The chromatographic assay was performed using a Waters Corp Acquity UPLC® H-Class system and a Waters Corp Acquity UPLC® BEH C18 column, with a mobile phase of 20% Acetonitrile and 80% Acetate Buffer pH 3.4, flow rate of 0.3 mL/min, and total duration of 4.5 minutes. Results: The results showed a decrease in Lidocaine HCl levels to 1.88% after re-sterilization and 2.01% without re-sterilization. Conclusion: These findings suggest that re-sterilization with hydrogen peroxide plasma sterilization leads to a significant decrease in Lidocaine HCl levels, causing non-compliance with pharmacopoeia standards.

Green UPLC method for estimation of ciprofloxacin, diclofenac sodium, and ibuprofen with application to pharmacokinetic study of human samples

Investigation of a unique and fast method for the determination and separation of a mixture of three drugs viz., ciprofloxacin (CIP), Ibuprofen (IBU), and diclofenac sodium (DIC) in actual samples of human plasma. Also, the technique was used to look at their pharmacokinetics study. Hydrocortisone was chosen as the internal standard (IS). The drugs were chromatographically separated using an Acquity ultra-performance liquid chromatography UPLC ® BEH C18 1.7 µm (2.1 × 150 mm) column with a mobile phase composed of acetonitrile: water (65:35, v/v) adjusted to pH 3 with diluted acetic acid. Plasma proteins were precipitated with acetonitrile. The separated drugs ranged from 0.3 to 10, 0.2–11, and 1–25 µg/mL for CIP, IBU, and DIC, respectively. Calibration curves were discovered to achieve linearity with acceptable correlation coefficients (0.99%). Examination of quality assurance samples showed exceptional precision and accuracy. Following the successful application of this improved technique to plasma samples, the pharmacokinetic characteristics of each selected drug were evaluated using (UPLC) with UV detection at 210 nm. Two green metrics were applied, the Analytical Eco-scale and the Analytical GREEnness Calculator (AGREE). Separation was achieved in only 4-min analysis time. The method's validation agreed with the requirements of the FDA, and the results were sufficient.

Levels of organophosphate flame retardants and their metabolites among 391 volunteers in Taiwan: difference between adults and children.

Organophosphate flame retardants (OPFRs) are ubiquitous in the environment. The compositions and concentrations of different OPFRs metabolites vary in different environments depending on different human activities. The objective of the present study was to evaluate the exposure of different age groups to OPFRs in Taiwan. Volunteers provided urine samples and responded to questionnaires including demographic factors, underlying disease, lifestyle information, and occupation from October 2021 to January 2022. OPFR measurements were performed using a Waters Acquity Ultra-Performance Liquid Chromatography system coupled with a Waters Xevo TQ-XS mass spectrometer. A total of 391 volunteers (74 children and 317 adults) were enrolled in this study. The concentrations (presented as μg/g creatinine) of bis(1,3-dichloro-2-propyl) phosphate (BDCPP, p = 0.029) and tri-n-butyl phosphate (TNBP, p = 0.008) were higher in the adult group, while the concentrations of bis-2-chloroethyl phosphate (BCEP, p = 0.024), diphenyl phosphate (DPHP, p < 0.001), tris(1,3-dichloro-2-propyl) phosphate (TDCPP, p = 0.009), and Tris(2-butoxyethyl) phosphate (TBEP, p = 0.007) were higher in the child group. Compared with school age children (>6 years), the concentration of di(2-n-butoxyethyl) phthalate (DBEP, 1.14 vs. 0.20 μg/g creatinine, p = 0.001), DPHP (1.23 vs. 0.54 μg/g creatinine, p = 0.036), TBEP (1.63 vs. 0.29 μg/g creatinine, p < 0.001), and the sum of OPFR metabolites (ΣOPFRs, 6.58 vs. 2.04 μg/g creatinine, p < 0.001) were statistically higher in preschool-aged children. After adjusting for confounding factors, pre-school age [odds ratio (OR): 4.579, 95% confidence interval (CI): 1.389-13.115] and current smoker (OR: 5.328, 95%CI: 1.858-14.955) were independently associated with the risk of ΣOPFRs higher than 90 percentile. This study revealed the distribution of different OPFRs metabolites in children and adults. DBEP, DPHP, TBEP, and ΣOPFR were higher in preschool-aged children. Pre-school age and current smoking status were independent risk factors for ΣOPFRs higher than 90 percentile.

Simultaneous determination of five indole/indazole amide-based synthetic cannabinoids in electronic cigarette oil by ultra performance liquid chromatography

Synthetic cannabinoids (SCs), which are considered some of the most widely abused new psychoactive substances available today, are much more potent than natural cannabis and display greater efficacy. New SCs can be developed by adding substituents such as halogen, alkyl, or alkoxy groups to one of the aromatic ring systems, or by changing the length of the alkyl chain. Following the emergence of the so-called first-generation SCs, further developments have led to eighth-generation indole/indazole amide-based SCs. Given that all SCs were listed as controlled substances on July 1, 2021, the technologies used to detect these substances must be quickly improved. Due to the sheer number of SCs, the chemical diversity and the fast update speed, it is challenging to determine and identify the new SCs. In recent years, several types of indole/indazole amide-based SCs have been seized, but systematic research on these compounds remains limited. Therefore, developing rapid, sensitive, and accurate quantitative methods to determine new SCs are of great importance. Compared with high performance liquid chromatography (HPLC), ultra performance liquid chromatography (UPLC) shows higher resolution, better separation efficiency, and faster analysis speeds; thus, it can meet the demand for the quantitative analysis of indole/indazole amide-based SCs in seized materials. In this study, a UPLC method was developed for the simultaneous determination of five indole/indazole amide-based SCs, including N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-butyl-1H-indazole-3-carboxamide (ADB-BUTINACA), methyl 2-(1-(4-fluorobutyl)-1H-indole-3-carboxamido)-3,3-dimethylbutanoate (4F-MDMB-BUTICA), N-(1-methoxy-3,3-dimethyl-1-oxobutan-2-yl)-1-(5-fluoropentyl)-1H-indole-3-carboxamide (5F-MDMB-PICA), methyl 3,3-dimethyl-2-(1-(pent-4-en-1-yl)-1H-indazole-3-carboxamido)butanoate (MDMB-4en-PINACA), and N-(adamantan-1-yl)-1-(4-fluorobutyl)-1H-indazole-3-carboxamide (4F-ABUTINACA) in electronic cigarette oil; these SCs have been detected with increasing frequency in seized materials in recent years. The main factors influencing the separation and detection performance of the proposed method, including the mobile phase, elution gradient, column temperature, and detection wavelength, were optimized. The proposed method successfully quantified the five SCs in electronic cigarette oil via the external standard method. The samples were extracted using methanol, and the target analytes were separated on a Waters ACQUITY UPLC CSH C18 column (100 mm×2.1 mm, 1.7 μm) at column temperature of 35 ℃ and flow rate of 0.3 mL/min. The injection volume was 1 μL. The mobile phase consisted of acetonitrile and ultrapure water, and gradient elution was employed. The detection wavelengths were 290 and 302 nm. The five SCs were completely separated within 10 min under optimized conditions and showed good linear relationships between 1-100 mg/L, with correlation coefficients (r2) of up to 0.9999. The limits of detection (LOD) and quantification (LOQ) were 0.2 and 0.6 mg/L, respectively. Precision was determined using standard solutions of the five SCs at mass concentrations of 1, 10, and 100 mg/L. The intra-day precision (n=6) was <1.5%, and the inter-day precision (n=6) was <2.2%. Accuracy was determined by spiking electronic cigarette oil with low (2 mg/L), moderate (10 mg/L), and high (50 mg/L) levels of the five SCs, with six replicates per determination. The recoveries of the five SCs were 95.5%-101.9%, and their relative standard deviations (RSDs, n=6) were 0.2%-1.5%, with accuracies ranging from -4.5% to 1.9%. The proposed method showed good performance when applied to the analysis of real samples. It is accurate, rapid, sensitive, and effective for the determination of five indole/indazole amide-based SCs in electronic cigarette oil. Thus, it satisfies the requirements for practical determination and provides a reference for the determination of SCs with similar structures by UPLC.

Characterization of famotidine API and simultaneous Quantification of its organic impurities by UPLC

To evaluate the characterization of Famotidine API (active pharmaceutical ingredient) and develop the accurate, precise, linear ultra-performance liquid chromatographic (UPLC) method for quantitating determination of organic impurities (Impurity-A, Impurity-B, and Impurity-C) in Famotidine API, pharmaceutical dosage forms and the method has been validated as per international council of harmonization (ICH) guidelines. The Famotidine API characterization was done by using spectroscopic techniques such as mass, infrared spectroscopy (IR), differential scanning calorimetry (DSC), proton nuclear magnetic resonance (1H-NMR), Carbon-13 nuclear magnetic resonance (C13-NMR), and two-dimensional nuclear magnetic resonance (2D-NMR). The organic impurities (A, B, and C) quantification was done using ACQUITY UPLC CSH C18- 100 mm × 2.1 mm, 1.7 μm column connected to ACQUITY UPLC with PDA detector. The optimized chromatographic conditions were achieved at 0.3 mL/min flow rate using a gradient system with 0.1% Tri fluoro acetic acid in water acetonitrile and Methanol as mobile phase. Three organic impurities are measured at λmax 260 nm at 45°C column temperature. Famotidine structure was confirmed by the appraised complete characterization data. The coefficient of correlation (r2) for the Impurity-A, Impurity-B, and Impurity-C was obtained not less than 0.99. The limit of detection (LOD) obtained 0.12 µg/mL and the limit of quantification (LOQ) obtained 0.4 µg/mL for each impurity concerning Famotidine test concentration. The method was fully validated as precision, accuracy, LOQ precision, LOQ accuracy, ruggedness, and robustness complying with FDA, ICH, AOAC, and European medicines agency (EMEA) guidelines. The characterization study and the proposed UPLC method were specific, accurate, precise, linear, rugged, and robust for the determination of the three organic impurities in Famotidine API and it can be implemented for its intended use in pharmaceutical industries.

A Simple Stability-Indicating UPLC Method for the Concurrent Assessment of Paracetamol and Caffeine in Pharmaceutical Formulations

A fixed-dose combination of paracetamol (PCM) and caffeine (CAF) tablets/capsules is the most frequently used over-the-counter medicine for fever and headache. In this paper, a simple, reliable, sensitive, rapid, and stability-indicating ultra-performance liquid chromatography (UPLC) analytical method was proposed for simultaneously assessing PCM and CAF in pharmaceutical formulations. The UPLC method was developed on an Acquity UPLC® CSHTM C18 column, and the column oven temperature was maintained at 35 ± 5 °C with isocratic elution by using a solution of methanol and water (30:70, v/v). The maximum absorbance of PCM and CAF was observed at 272.5 nm. The flow rate was 0.2 mL/min, and the injection volume was 1 µL, with the total run time of 2 min for the separation of PCM and CAF. The proposed UPLC method was validated according to the ICH guidelines, and it demonstrated excellent linearity, with correlation coefficients of 0.9995 and 0.9999 over the concentration ranges of 40–400 and 7–70 ng/mL for PCM and CAF, respectively. The mean retention times of 0.82 ± 0.0 and 1.16 ± 0.02 were observed for PCM and CAF, respectively. The limits of detection and quantification were 16.62 and 3.86 for PCM, respectively, and 50.37 and 11.70 for CAF, respectively. PCM and CAF were subjected to acidic, alkali, oxidative, phytochemical, dry-heat, and wet-heat degradation. The method was found to well separate the analytes’ peaks from degradation peaks, with no alterations in retention times. The proposed method is linear, precise, accurate, specific, and robust, and it can indicate stability and be used for the quantitative assessment of pharmaceutical formulations comprising PCM and CAF within a short period of time.

Detection of Neonicotinoid Insecticides and Their Metabolites in Human Cerebrospinal Fluid.

Detection of Neonicotinoid Insecticides and Their Metabolites in Human Cerebrospinal Fluid.

Cellular toxicity and pharmacokinetic study of butachlor by ultra-performance liquid chromatography-tandem mass spectrometry based on tandem mass spectrometry cubed technique.

Butachlor is an aromatic amide compound that plays a role as a herbicide, a xenobiotic, and an environmental contaminant. The aim of this work was to develop a highly selective and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method based on the tandem mass spectrometry cubed technique to determine butachlor in a biological matrix. Butachlor and internal standard acetochlor were separated on a Waters Acquity ultra-performance liquid chromatography BEH C18 column (2.1 × 50mm, 1.7μm) with gradient elution using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as mobile phases. The transitions selected for tandem mass spectrometry cubed quantitative analysis in positive ion mode were: for butachlor, mass-to-charge ratio 312.2→238.1→162.1; for acetochlor, mass-to-charge ratio 270.1→224.0→148.1. The total running time for each sample was 5.5 min. The ultra-performance liquid chromatography-tandem mass spectrometry cubed method showed a linear relationship (R2 ≥ 0.995) in the concentration range of 0.5-100ng/ml. The intra and interday accuracies are within the range of -10.6%-4.3% and precisions are between 4.48% and 13.14%. The novelty of the method is the use of tandem mass spectrometry cubed scanning mode, which improves selectivity and sensitivity. The results indicated that butachlor was cellular toxic. The safety of butachlor should be considered when it is used as a herbicide.

Untargeted Metabolomics Identifies a Novel Panel of Markers for Autologous Blood Transfusion.

Untargeted metabolomics was used to analyze serum and urine samples for biomarkers of autologous blood transfusion (ABT). Red blood cell concentrates from donated blood were stored for 35–36 days prior to reinfusion into the donors. Participants were sampled at different time points post-donation and up to 7 days post-transfusion. Metabolomic profiling was performed using ACQUITY ultra performance liquid chromatography (UPLC), Q-Exactive high resolution/accurate mass spectrometer interfaced with a heated electrospray ionization (HESI-II) source and Orbitrap mass analyzer operated at 35,000 mass resolution. The markers of ABT were determined by principal component analysis and metabolites that had p < 0.05 and met ≥ 2-fold change from baseline were selected. A total of 11 serum and eight urinary metabolites, including two urinary plasticizer metabolites, were altered during the study. By the seventh day post-transfusion, the plasticizers had returned to baseline, while changes in nine other metabolites (seven serum and two urinary) remained. Five of these metabolites (serum inosine, guanosine and sphinganine and urinary isocitrate and erythronate) were upregulated, while serum glycourdeoxycholate, S-allylcysteine, 17-alphahydroxypregnenalone 3 and Glutamine conjugate of C6H10O2 (2)* were downregulated. This is the first study to identify a panel of metabolites, from serum and urine, as markers of ABT. Once independently validated, it could be universally adopted to detect ABT.

A quantitative method for the simultaneous detection of SR9009 and SR9011 in equine plasma using liquid chromatography-electrospray ionization-tandem mass spectrometry.

SR9009 and SR9011 are metabolic modulators pharmacologically targeting REV-ERB receptors as synthetic agonists. A liquid chromatography-tandem mass spectrometry method for the detection of SR9009 and SR9011 in equine plasma was developed and validated. Plasma samples were pretreated by protein precipitation with methanol and were loaded onto an ACQUITY ultra performance liquid chromatography high-strength silica C18 column (2.1 × 150 mm, 1.8 μm) for chromatographic separation. The mobile phase consisted of 5-mM ammonium formate (pH 3.0) in distilled water and 0.1% formic acid in acetonitrile, and a gradient elution was used at a flow rate of 0.25 ml/min. For the mass spectrometry detection, the selected reaction monitoring mode was used with transitions of 438.2 → 124.9 for SR9009, 479.2 → 125.1 for SR9011, and 292.2 → 109.1 for the internal standard (testosterone-d3) in the positive ionization mode. The linearity, lower limit of quantification, intra- and inter-day precision, accuracy, matrix effect, recovery, and stability were evaluated. The method was found to be accurate and reproducible for the quantitation of SR9009 and SR9011. The developed method was successfully applied to plasma samples of thoroughbreds injected intramuscularly with SR9009.

Antibiotic Residues in Waste Impacted Surface Waters from Lagos, Nigeria

In the past few decades, there has been increasing interest and concern about the environmental presence of human and veterinary pharmaceutically active chemicals (PHACs). and the implication of such on ecosystem health at organismal and population levels This study was conceived, to identify and quantify the concentrations of an important sub-group i.e., the pharmaceuticals. Which have been shown to have ecological implications on various aquatic life-forms. In surface water bodies in Lagos Nigeria.&#x0D; Study Design: water specimens taken from six locations in the city of Lagos in Nigeria were analysed using SPE coupled with tandem LC/MS.&#x0D; Place and Duration of Study: The project, split site collaboration. Spanned a period of nine months between 30.09.2013 to 30.04.2014. Analysis of water specimens was done at the IWW Water Centre. Mulheim, Germany.&#x0D; Methodology: Analysis of water samples were carried out by IWW Water Centre, Mulheim, Germany according to published guidelines or validated in-house methods. Waters Acquity ultra performance liquid chromatography (UPLC-TQD/PDA and UPLC-TQS) (Milford) was used to carry out LC-MS/MS analyses. For GC-MS analyses an Agilent GC-MS system (6890 GC and 5973 MSD single quadrupole mass analyzer was used.&#x0D; Results: In surface water samples, 12 pharmaceutical agents were detected. Of these Six antibiotics, Viz: Chloramphenicol,Erythromycin,Erythromycin-A dehydrate,Sulfadiazine, and Sulphaamethoxazole.&#x0D; Trimetoprim were detected out of thirteen screened for, at environmentally significant concentrations.&#x0D; Conclusion: This study has established the precence and locational prevalence of primary antibiotic and antibiotic degradates in surface waters in Lagos, Nigeria More studies are required to investigate the ecological implications of such presences.

Simultaneous quantitative analysis of 39 common toxicological drugs for increased efficiency in an ante- and postmortem laboratory

BackgroundA novel forensic method was developed to quantitate 39 drugs of toxicological interest for ante-mortem and postmortem analysis. This method was created to combine and replace four existing quantitation methods as well as add three additional compounds of interest and serves to drastically increase the efficiency of the criminalists and reduce the case backlog. The method is currently applied to ante-mortem blood, postmortem blood, urine, liver, brain, and gastric contents. MethodsThe extraction was performed by using a protein precipitation and DPX WAX-S tips with analysis on a Waters® i-class Acquity ultra-performance liquid chromatography with a Phenomenex Kinetex® Column (1.7 µm Biphenyl Å, 2.1 ×100 mm) followed by a Waters® XeVo-TQS tandem mass spectrometer using positive electrospray ionization in multiple reaction monitor mode. The sample volume required for analysis was 0.5 mL, or 0.5 g, an improvement from 4 mL when performing previous methods utilized in the laboratory. ResultsThe improved method incorporated the 2017 recommended cut-offs for toxicological investigation of driving under the influence of drugs and was validated following the SWGTOX and ANSI/ASB guidelines of method validation. The advantages of analyzing low volume cases and/or detecting drugs previously outside the laboratory’s scope of analysis, (such as gabapentin, pregabalin and baclofen) will be presented in two case studies. ConclusionThe multi-drug quantitation method allowed for the analysis of 39 drugs including a hydrolysis step, if needed, with only 0.5 mL or 0.5 g of sample. The method condensed two previously un-validated quantitative methods and two additional qualitative methods, which detected many commonly seen drugs, all into a single method. Three additional analytes of interest, gabapentin, pregabalin and baclofen, which it had previously been unable to detect, were added to the new method. The added benefit of these new drugs added both the coroner’s investigators in cause of death determination and driving under the influence of drugs investigation especially with the high prevalence of gabapentin.

Nitrites as precursors of N-nitrosation in pharmaceutical samples – A trace level analysis

The ultra-performance liquid chromatography (UPLC) method, which involves pre-column derivatization of nitrite with 2,3-diaminonaphthalene (DAN) to form 2,3-naphthotriazole (NAT), offers the advantages of easy sample preparation, simple derivatization, stable derivatives, rapid analysis, high sensitivity and specificity and lack of interferences for determining nitrite in pharmaceutical samples. Determination of NAT was performed on a an Acquity UPLC HSS T3 column using a gradient elution of 0.1% formic acid with acetonitrile at flow rate of 0.4 mL/min and temperature at 45 °C. The single-quadrupole mass detector was operated in the positive ion mode. Quadrupole mass analyser was employed in selected ion monitoring mode using a target ion at m/z = 170 as [M+H]+. The UPLC-MS method was validated as per International Council on Harmonization (ICH) guidelines in terms of linearity, limit of detection, limit of quantification, selectivity, accuracy, precision, intermediate precision and stability. The UPLC-MS method was demonstrated to be applicable for the determination of nitrite in various pharmaceutical samples. The proposed UPLC-MS method was used to study the effect of nitrite content in pharmaceutical products on the formation of N-nitrosamines. The high importance of nitrites in relation to the N-nitrosation reaction was discussed. As deduced from theory and justified by the presented results, reducing the nitrite concentration could definitely solve the N-nitrosamine contamination. Nitrites, unlike secondary and tertiary amines, are universal precursors to any N-nitrosamine, so this solution is easily transferable to any relevant pharmaceutical product.

Development and Validation of Ultra Performance Liquid Chromatography (UPLC) Method for the Quantitative Estimation of Caffeine in Non-Alcoholic Soft and Energy Drinks.

The popularity of beverages such as cold coffee, iced tea, and energy drinks has risen tremendously among athletes and youths. Energy drinks are used to enhance performance due to the presence of a high amount of caffeine (CFN) and sugars, as well as other constituents such as vitamins, amino acids, taurine, extracts of Ginkgo biloba, ginseng, guarana, and other herbal products. Commercial drinks are promoted as being beneficial to health; thus it is an important concern regarding adverse effects linked with these drinks or products. The aim of the study is to develop and validate the ultra performance liquid chromatography-photodiode array detector (UPLC-PDA) method for the estimation of CFN in eight marketed non-alcoholic drinks including two soft drinks and six energy drinks. The chromatographic separation of CFN was achieved on Acquity UPLC® CSHTM C18 1.7 µm, 2.1 × 100 mm column, using isocratic mode, mobile phase comprising acetonitrile and water (30:70, v/v) at a flow rate 0.3 mL/min using injection volume 1 µL. The elution of CFN occurred at 1.06 min, and the calibration curve of the CFN was computed from the peak area ratio detected at 273 nm. All the validation parameters were found within the assay variability limits as per ICH guidelines. The obtained results revealed that the soft drinks SD1 and SD2 have 87.21 ± 1.28 and 101.81 ± 1.52% (w/w), whereas CFN concentration in energy drink brands ED1, ED2, ED3, ED4, ED5, and ED6 was 95.90 ± 1.62, 64.0 ± 1.07, 76.68 ± 1.95, 74.97 ± 2.33, 82.09 ± 2.43, and 88.04 ± 2.94% (w/w) of labeled claims, respectively. The developed UPLC method was found suitable for the quality control of commercial soft and energy drinks containing CFN. The developed chromatographic method is very simple, cost effective and could be utilized for the routine analysis of caffeine in the soft and energy drinks.

A Novel UPLC Method for Simultaneous Estimation of Ertugliflozin and Sitagliptin in Bulk and Tablet Dosage Form

Aim: The proposed study aimed to develop a novel ultra-performance liquid chromatography (UPLC) method for the estimation of Ertugliflozin and Sitagliptin in Bulk and Tablet dosage form and validate the method in accordance with the International Conference on Harmonization guidelines. Methods: The optimized conditions for the developed UPLC method are Acquity UPLC HIBRA C18 (100mm × 2.1mm, 1.8µ) column maintained at 30°C with a mobile phase consisting of Buffer (0.01N sodium hydrogen phosphate) pH adjusted to 4.0 with dil. orthophosphoric acid: Acetonitrile in the ratio of 60:40%v/v on isocratic mode at a flow rate of 0.3mL/min. Results and conclusion: The sample was detected at 220nm. The retention time for Ertugliflozin and Sitagliptin was deemed at 1.873min and 1.260min. The developed method was validated for accuracy, precision, specificity, ruggedness, robustness, and solution stability. The method obeyed Beer’s law in the concentration range of 3.75µg/mL to 22.5µg/mL for Ertugliflozin and 25µg/mL to 150µg/mL for Sitagliptin with a correlation coefficient of 0.999 for Ertugliflozin and Sitagliptin respectively. Forced degradation studies were conducted by exposing the drug solution to numerous stress conditions such as acidic, basic, peroxide, neutral, photolytic, and thermal conditions. The net degradation was considered within the limits, indicating that the drug is stable in stressed conditions. The developed method for the estimation of Ertugliflozin and Sitagliptin can be utilized for the routine analysis of Pharmaceutical dosage form.

Facile Access to Polar-Functionalized Ultrahigh Molecular Weight Polyethylene at Ambient Conditions

Facile Access to Polar-Functionalized Ultrahigh Molecular Weight Polyethylene at Ambient Conditions