UPLC versus HPLC on Drug Analysis: Advantageous, Applications and Their Validation Parameters

Development of a Validated UPLC-MS/MS Method for Simultaneous Estimation of Neratinib and Curcumin in Human Plasma: Application to Greenness Assessment and Routine Quantification

A validated ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the first-ever simultaneous analysis of neratinib, curcumin and internal standard (imatinib) using acetonitrile as the liquid-liquid extraction medium. On a BEH C18 (100 mm × 2.1 mm, 1.7 μm) column, the analytes were separated isocratically using acetonitrile (0.1% formic acid):0.002M ammonium acetate. The flow rate was set at 0.5 mL.min-1. The authors utilized multiple reaction monitoring-based transitions for the precursor-to-product ion with m/z 557.099 → 111.928 for neratinib, m/z 369.231 → 176.969 curcumin and m/z 494.526 → 394.141 for imatinib during the study. Validation of the method as per United States Food and Drug Administration requirements for linearity (5-40 ng mL-1), accuracy and precision, stability, matrix effect, etc. were investigated and were observed to be acceptable. Afterward, we evaluated the method for establishing its greenness profile by using two greenness assessment tools and found it green. Overall, a reliable green UPLC-MS/MS method was devised and used to estimate neratinib and curcumin in human plasma simultaneously.

Preparation and application of UPLC silica microsphere stationary phase:A review

In this review, microspheres for ultra-performance liquid chromatography (UPLC) were reviewed in accordance with the literature in recent years. As people's demands for chromatography are becoming more and more sophisticated, the preparation and application of UPLC stationary phases have become the focus of researchers in this field. This new analytical separation science not only maintains the practicality and principle of high-performance liquid chromatography (HPLC), but also improves the step function of chromatographic performance. The review presents the morphology of four types of sub-2 μm silica microspheres that have been used in UPLC, including non-porous silica microspheres (NPSMs), mesoporous silica microspheres (MPSMs), hollow silica microspheres (HSMs) and core-shell silica microspheres (CSSMs). The preparation, pore control and modification methods of different microspheres are introduced in the review, and then the applications of UPLC in drug analysis and separation, environmental monitoring, and separation of macromolecular proteins was presented. Finally, a brief overview of the existing challenges in the preparation of sub-2 μm microspheres, which required further research and development, was given.

Improved Stability-Indicating RP-UPLC Method for the Levamisole Hydrochloride Assay and Estimation of Its Related Compounds

BACKGROUND

Levamisole hydrochloride (LVM) is an anthelmintic drug substance with immunomodulatory and anticancer activities. LVM has also found usage as a cutting agent in street cocaine.

OBJECTIVE

This study was aimed to develop and validate an alternative and improved stability-indicating reversed-phase ultraperformance liquid chromatography (RP-UPLC) method for the determination of LVM and the estimation of its related compounds.

METHOD

The UPLC method for the assay was optimized in terms of organic solvents consumed, pH, column temperature, and flow rate. Determination of LVM and its related compounds was performed using a gradient elution on a Waters ACQUITY UPLC® BEH C18 (50 mm × 2.1 mm i.d., 130 Å). The column temperature was maintained at 35°C. Mobile phase A was composed of aqueous 5 mM ammonium hydroxide, and mobile phase B was composed of acetonitrile. All the analytes were monitored by UV detection at 215 nm with a flow rate of 0.7 mL/min. The total runtime of the method with column equilibration is 4.0 min.

RESULTS

The developed method met all the acceptance criteria of the current International Council for Harmonization [ICH Q2 (R1)] guidelines. The method was tested in terms of specificity, linearity (R2 > 0.999), limit of detection (LOD; 0.06 μg/mL), limit of quantitation (LOQ; 0.2 μg/mL), accuracy, precision, and robustness. With a short analysis time (<2.5 min) and reduced consumption of organic solvents, the proposed method is considered a greener alternative to conventional chromatographic methods.

CONCLUSIONS

An alternative and improved UPLC method was successfully developed and validated in accordance with the ICH guidelines for the determination of LVM and the estimation of its related compounds.

HIGHLIGHTS

Due to its high degree of selectivity, speed, and accuracy, the developed method can significantly benefit the end-users with laboratory efficiency and throughput during routine analysis of production batches and stability monitoring of LVM-related drug products.

Analytical studies on some pesticides with antifungal effects: Simultaneous determination by HPLC, investigation of interactions with DNA and DNA damages

A simple, and fast method was developed for the simultaneous determination of five fungicides, namely thiram (THR), epoxiconazole (EPO), hexaconazole (HEX), tebuconazole (TEB), and diethofencarb (DIE), in different matrices by HPLC-UV. Parameters influencing the peak shape and resolution, such as the composition of mobile phase, pH and concentration of buffer solution, and column temperature, were examined and optimized. The proposed method was validated in terms of linearity, sensitivity, precision, and accuracy. Forced degradation studies were carried out for all analytes to demonstrate the specificity of the method and to evaluate the stability of analytes under different conditions. DNA interaction and DNA damage studies were conducted by HPLC and comet assay, respectively. All fungicides were found to bind DNA, except for DIE. While the binding coefficients for EPO, HEX, and TEB were of the order of 104, THR was found to interact more strongly with DNA with a binding coefficient of higher than 106. DIE did not induce DNA damage at any concentration tested. On the other hand, TEB, HEX, and EPO induced DNA damage up to 30 µg/mL. THR showed cytotoxic effects at 20 and 30 µg/mL and caused significant DNA damage at lower concentrations.

Exploiting the power of UPLC in separation and simultaneous determination of pholcodine, guaiacol along with three specified guaiacol impurities

Pholcodine and guaiacol are widely used together in pharmaceutical syrups for cough treatment. On the other hand, the Ultra Performance Liquid Chromatographic technique is characterized by having the power of increasing chromatographic efficiency and decreasing run time compared to the traditional High Performance Liquid Chromatographic one. In this work, this power was exploited for the simultaneous determination of pholcodine, guaiacol along with three guaiacol impurities, namely; guaiacol impurity A, guaiacol impurity B, and guaiacol impurity E. Good separation was achieved by employing Agilent Zorbax C8 column (50 × 2.1 mm) as the stationary phase, and acetonitrile: phosphate buffer pH 3.5 (40: 60, by volume) as a mobile phase. The proposed method was validated as per International Council for Harmonisation guidelines. Linear relationships, at ranges of 50-1000 µg mL^-1 for pholcodine and 5-100 µg mL^-1 for guaiacol and the three related impurities, were established. Finally, the proposed method was applied for pholcodine and guaiacol determination in Coughpent® syrup and compared favorably to the reported one.

Rapid detection and quantification of paracetamol and its major metabolites using surface enhanced Raman scattering

Paracetamol (also known as acetaminophen) is an over-the-counter (OTC) drug that is commonly used as an analgesic for mild pain, headache, cold and flu. While in the short term it is a safe and effective medicine, it is sometimes used for attempted suicides particularly in young adults. In such circumstances it is important for rapid diagnosis of overdoses as antidotes can be given to limit liver damage from one of its primary metabolites N-acetyl-p-benzoquinone imine (NAPQI). Unfortunately, the demand for rapid and sensitive analytical techniques to accurately monitor the abuse of OTC drugs has significantly risen. Ideally these techniques would be highly specific, sensitive, reproducible, portable and rapid. In addition, an ideal point of care (PoC) test would enable quantitative detection of drugs and their metabolites present in body fluids. While Raman spectroscopy meets these specifications, there is a need for enhancement of the signal because the Raman effect is weak. In this study, we developed a surface-enhanced Raman scattering (SERS) methodology in conjunction with chemometrics to quantify the amount of paracetamol and its main primary metabolites (viz., paracetamol sulfate, p-acetamidophenyl β-D-glucuronide and NAPQI) in water and artificial urine. The enhancement of the SERS signals was achieved by mixing the drug or xenometabolites with a gold nanoparticle followed by aggregation with 0.045 M NaCl. We found that the SERS data could be collected directly, due to immediate analyte association with the Au surface and colloid aggregation. Accurate and precise measurements were generated, with a limit of detection (LoD) of paracetamol in water and artificial urine at 7.18 × 10^-6 M and 2.11 × 10^-5 M, respectively, which is well below the limit needed for overdose and indeed normal levels of paracetamol in serum after taking 1 g orally. The predictive values obtained from the analysis of paracetamol in water and artificial urine were also excellent, with the coefficient of determination (Q²) being 0.995 and 0.996, respectively (1 suggests a perfect model). It was noteworthy that when artificial urine was spiked with paracetamol, no aggregating agent was required due to the salt rich medium, which led to spontaneous aggregation. Moreover, for the xenometabolites of paracetamol excellent LoDs were obtained and these ranged from 2.6 × 10^-4 M to 5 × 10^-5 M with paracetamol sulfate and NAPQI having Q² values of 0.934 and 0.892 and for p-acetamidophenyl β-D-glucuronide this was slightly lower at 0.6437.

A review of conventional and rapid analytical techniques coupled with multivariate analysis for origin traceability of soybean

Soybean has developed a reputation as a superfood due to its nutrient profile, health benefits, and versatility. Since 1960, its demand has increased dramatically, going from a mere 17 MMT to almost 358 MMT in the production year 2021/22. These extremely high production rates have led to lower-than-expected product quality, adulteration, illegal trade, deforestation, and other concerns. This necessitates the development of an effective technology to confirm soybean's provenance. This is the first review that investigates current analytical techniques coupled with multivariate analysis for origin traceability of soybeans. The fundamentals of several analytical techniques are presented, assessed, compared, and discussed in terms of their operating specifics, advantages, and shortcomings. Additionally, significance of multivariate analysis in analyzing complex data has also been discussed.

UPLC Technique in Pharmacy—An Important Tool of the Modern Analyst

In recent years, ultra-efficient liquid chromatography (UPLC) has gained particular popularity due to the possibility of faster separation of small molecules. This technique, used to separate the ingredients present in multi-component mixtures, has found application in many fields, such as chemistry, pharmacy, food, and biochemistry. It is an important tool in both research and production. UPLC created new possibilities for analytical separation without reducing the quality of the obtained results. This technique is therefore a milestone in liquid chromatography. Thanks to the increased resolution, new analytical procedures, in many cases, based on existing methods, are being developed, eliminating the need for re-analysis. Researchers are trying to modify and transfer the analytical conditions from the commonly used HPLC method to UPLC. This topic may be of strategic importance in the analysis of medicinal substances. The information contained in this manuscript indicates the importance of the UPLC technique in drug analysis. The information gathered highlights the importance of selecting the appropriate drug control tools. We focused on drugs commonly used in medicine that belong to various pharmacological groups. Rational prescribing based on clinical pharmacology is essential if the right drug is to be administered to the right patient at the right time. The presented data is to assist the analyst in the field of broadly understood quality control, which is very important, especially for human health and treatment. This manuscript shows that the UPLC technique is now an increasingly used tool for assessing the quality of drugs and determining the identity and content of active substances. It also allows the monitoring of active substances and finished products during their processing and storage.

Identification, synthesis and characterization of avanafil process impurities and determination by UPLC

Avanafil is a phosphodiesterase type 5 inhibitor which is used to treat erectile dysfunction in men. The process-related impurities of avanafil were investigated, and four kinds of impurities in several laboratory batches with a content of 0.29-1.63% were detected by the newly developed gradient ultra-high performance liquid chromatography (UPLC). Based on the synthesis route and UPLC-MS research, the impurities are inferred as Imp-A, Imp-B, Imp-C and Imp-D. The structures of the impurities were inferred from LC-MS studies and confirmed by synthesis, followed by spectroscopic characterization such as NMR and mass spectrometry. Especially, the synthesis of Imp-D is firstly reported. The drug-related substances can be separated well by efficient and selective ultra-high performance liquid chromatography on a Waters ACQUITY HSS C18 (50 × 2.1 mm, particle size 1.8 μm) column at 35 °C, with the mobile phase consisting of ammonium formate (20 mM) and acetonitrile, and the detection at 239 nm with a DAD detector. The method was validated in terms of specificity, linearity, precision, accuracy and sensitivity, and satisfactory results were obtained. The results indicated this developed UPLC method for avanafil and the proposed synthesis mechanism can be used for quality control purposes as required by regulatory agencies to ensure the safety and efficacy of the product.

Determination of the pharmaceuticals-nano/microplastics in aquatic systems by analytical and instrumental methods

Pharmaceutical residues and nanoplastic and microplastic particles as emerging pollutants in the aquatic environment are a subject of increasing concern in terms of the effect on water sources and marine organisms. There is lack of information about pharmaceutical-nanoplastic and pharmaceutical-microplastic mixtures. The present study aimed to investigate the fate and effect of pharmaceutical residues and nanoplastic and microplastic particles, the results of combinations of pharmaceutical residues with nanoplastic and microplastic particles, and toxic effects of pharmaceutical residues and nanoplastic and microplastic particles. Moreover, the objective was also to introduce analytical methods for pharmaceuticals, along with instrumental techniques for nanoplastic and microplastic particles in aquatic environments and organisms. PhAC alone can affect marine environments and aquatic organisms. When pharmaceutical residues combine with nanoplastic and microplastic particles, the rate of toxicity increases, and the result of this phenomenon constitutes this kind of pollutant in wastewater. Hence, the rate of mortality in organisms enhances. This study aimed to investigate the effect of pharmaceuticals residues and nanoplastic and microplastic particles, and a mixture of pharmaceutical residues and nanoplastic and microplastic particles in aquatic biota. Another object was survey methods for recognizing pharmaceutical residues and nanoplastic and microplastic particles. The findings show that pharmaceutical residues in organisms caused cell structure damage, inflammatory response, and nerve cell apoptosis. This study aimed to investigate the effect of microplastic particles in the human food chain and their impact on human health. Moreover, this review aims to present an innovative methodology based on comprehensive analytical techniques used to determine and identify pharmaceuticals adsorbed on nano- and microplastics in aquatic ecosystems. Finally, this review addresses the knowledge gaps and provides insights into future research strategies to better understand their interactions.

A rapid and sensitive UPLC–MS/MS method for quantification of erdosteine as bulk drug and in capsules as dosage forms

A rapid, sensitive, specific ultra-performance liquid chromatography-tandem mass spectrometric (UPLC-MS-MS) method was developed for the determination of erdosteine (ERD) in pharmaceutical preparations. The chromatographic separation was achieved with 0.1% formic acid in combination with acetonitrile (25:75 v/v) using C18 UPLC column, 95Å, 2.1 x 50 mm, 1.8 µm. The flow rate was 0.15 mL/min and the total run time was 2.0 min. The column temperature was kept constant at 40 °C and the injection volume was 5 μL. Ibuprofen was used as internal standard (IS). The mass transitions of ERD and IS were m/z 249.9 → 231.8 and 205.1 → 161.0. Also, another product ion of ERD (m/z 249.80 → 231.80) was monitored as predictive ion during the analysis. The standard calibration curve shows determination coefficient (R2) greater than 0.996 with a range of 1-5000 ng/mL using the linear regression model. Within-run precision and between-run repeatability were expressed as relative standard deviation and were lower than 5%. The developed method was successfully applied in the analysis of ERD-containing capsule formulation indicating that the method could be used for routine quality control analyses. Keywords: erdosteine, UPLC-MS/MS, multiple reaction monitoring, pharmaceutical analysis, method validation

Does bisphenol A bioaccumulate on zebrafish? Determination of tissue bisphenol A level

Bisphenol A (BPA) is a high-production-volume industrial chemical mainly used in the production of polycarbonates and epoxy resins utilized in the manufacture of containers, bottles, toys, and medical devices. It has systemic effects as an endocrine disruptor even at low doses. To analyze its quantity in biological materials, sensitive and reproducible methods have to be used. Different doses and duration (90 and 900 μg/L, 24 and 120 h, and 21 days) of BPA exposure to whole body zebrafish were analyzed after specific homogenization of tissue, and then a modified method HPLC was used. The mobile phase was acetonitrile and water using a gradient method of reversed-phase C18 column, and excitation = 227 nm/emission = 313 nm. The calibration curve for BPA using HPLC-fluorescence detection method was between a concentration range of 1 and 1000 ng/mL and linear, and r²  = 0.999. The mean and standard error of mean values were 4.29 ± 1.05, 2.50 ± 0.92, and 2.53 ± 0.68 for control; 10.43 ± 2.61, 11.46 ± 3.24, and 8.55 ± 3.11 for BPA-90 μg/L; and 17.78 ± 4.39, 21.55 ± 4.37, and 25.32 ± 3.25 for BPA-900 μg/L (24 h, 120 h, and 21 days, respectively). Although some statistical significance among dose/time was observed between two different dose-treated groups, statistical significance was not found in dose/time results within the group. However, the positive result of BPA in the control group can be explained by low-dose, chronic exposure or prevalence of endocrine-disrupting chemicals.

Recent Analytical Method for Detection of Chemical Adulterants in Herbal Medicine

Herbal medicine has become popular in recent years as an alternative medicine. The problem arises when herbal medicines contain an undeclared synthetic drug that is illegally added, since it is a natural product that does not contain any chemical drugs due to the potential cause of harmful effects. Supervision of herbal medicines is important to ensure that these herbal medicines are still safe to use. Thus, developing a reliable analytical technique for the determination of adulterated drugs in herbal medicine is gaining interest. This review aims to provide a recent analytical method that has been used within the past 5 years (2016-2021) for the determination of chemical adulterants in herbal medicine.

Comprehensive analysis of phenolic compounds from natural products: Integrating sample preparation and analysis

The comprehensive analysis of phenolic compounds from natural products comprises critical steps, including quantitative extraction, extract preparation, and chromatographic procedure. Performing these steps off-line requires a long time to obtain results, besides being laborious and more error-prone. This work discusses the concept and presents the details of assembling and validating a new system to comprehensively analyze phenolic compounds in natural products. The system is based on a bidimensional separation through the combination of pressurized liquid extraction with in-line solid-phase extraction coupled online with HPLC-PDA. The system proved to be able to perform a bidimensional separation to characterize the sample and ensure quantitative extraction of all detected components using the most appropriate extraction solvent gradient depending on the raw sample analyzed. The 1st dimension separation is achieved by PLE-SPE with a solvent gradient and differential interactions of extracted compounds with the adsorbent. The 2nd dimension presents the HPLC-PDA separation. The extraction/separation process can be monitored in real-time, and kinetic extraction curves for individual compounds can also be obtained to ensure quantitative extraction. Thus, the 2D PLE-SPE × HPLC-PDA may provide fast and precise comprehensive analyses of a large plethora of phenolic compounds, finding relevant applications in the chemical, food, pharmaceutical, and agricultural fields.

A Stability-Indicating Ultra Performance Liquid Chromato-Graphic (UPLC) Method for the Determination of a Mycophenolic Acid-Curcumin Conjugate and Its Applications to Chemical Kinetic Studies

A simple, precise, and accurate reversed-phase ultra-performance liquid chromatographic (UPLC) method was developed and validated for the determination of a mycophenolic acid-curcumin (MPA-CUR) conjugate in buffer solutions. Chromatographic separation was performed on a C18 column (2.1 × 50 mm id, 1.7 µm) with a gradient elution system of water and acetonitrile, each containing 0.1% formic acid, at a flow rate of 0.6 mL/min. The column temperature was controlled at 33 °C. The compounds were detected simultaneously at the maximum wavelengths of mycophenolic acid (MPA), 254 nm, and curcumin (CUR), or MPA-CUR, at 420 nm. The developed method was validated according to the ICH Q2(R1) guidelines. The linear calibration curves of the assay ranged from 0.10 to 25 μg/mL (r² ≥ 0.995, 1/x² weighting factor), with a limit of detection and a limit of quantitation of 0.04 and 0.10 μg/mL, respectively. The accuracy and precision of the developed method were 98.4-101.6%, with %CV < 2.53%. The main impurities from the specificity test were found to be MPA and CUR. Other validation parameters, including robustness and solution stability, were acceptable under the validation criteria. Forced degradation studies were conducted under hydrolytic (acidic and alkaline), oxidative, thermal, and photolytic stress conditions. MPA-CUR was well separated from MPA, CUR, and other unknown degradation products. The validated method was successfully applied in chemical kinetic studies of MPA-CUR in different buffer solutions.

Forensic profiling of non-volatile organic compounds in soil using ultra-performance liquid chromatography: a pilot study

Soil is of particular interest to the forensic community because it can be used as valuable associative evidence to link a suspect to a victim or a crime scene. Liquid chromatography is a powerful analytical tool for organic compound analysis. Recently, high-performance liquid chromatography (HPLC) has proven to be an efficient method for forensic soil analysis, especially in discriminating soils from proximity locations. However, ultra-performance liquid chromatography (UPLC), which is much more sensitive than HPLC, has never been explored in this context. This study proposed a UPLC method for profiling non-volatile organic compounds in three Malaysian soils (red, brown and yellowish-brown soils). The three soils were analysed separately to assess the effects of individual chromatographic parameters: (a) elution programme (isocratic vs. two gradient programmes); (b) flow rate (0.1 vs. 0.2 mL/min); (c) extraction solvent (acetonitrile vs. methanol) and (d) detection wavelength (230 vs. 254 nm). The injection volume and total run time were set to 5 µL and 35 min, respectively. Consequently, each soil sample gave 24 different chromatograms. Results showed that the most desirable chromatographic parameters were (a) isocratic elution; (b) flow rate at 0.2 mL/min and (c) acetonitrile extraction solvent. The proposed UPLC system is expected to be a feasible method for profiling non-volatile organic compounds in soil, and is more chemical-efficient than a comparable HPLC system.

Development of Reverse Phase Ultra-fast Liquid Chromatography Using Ion-pairing Reagent for Quantitative Assessment of Ceftriaxone in Rat Serum and Cerebrospinal Fluid

Background:

In case of meningitis, the meninges are inflamed and the blood brain barrier is distorted, therefore, there is no hindrance to drug penetration. The problem arises when the disease is at the verge of cure, the meninges become uninflamed and the permeability of the drug is reduced to such extend that it becomes nearly impossible to maintain the minimum inhibitory concentration of drug at the site of infection. This problem was overcome by formulating ceftriaxone loaded NLCs and administrating it through intraperitoneal route to Wistar Albino rat. For quantitative assessment of drugs in rat serum and cerebrospinal spinal fluid, a new RP-UFLC (reverse-phase ultra-fast liquid chromatography) method has been developed and validated.

Objective:

Development and validation of RP-UFLC (using ion-pairing reagent) method for accurate estimation of ceftriaxone in rat serum and CSF.

Methods:

Method validation is done according to the ICH Guidelines (Q2) for the estimation of ceftriaxone in rat serum and its CSF (cerebrospinal fluid) by the RP-UFLC method. The blood was collected from the rat tail vein and CSF was collected carefully from cisterna magna of the rats by a 23G syringe. The mobile phase was used in a ratio of 70:30%v/v of phosphate buffer with ion-pairing reagent and acetonitrile with a pH of 8.0

Results:

Limit of detection and limit of quantification of ceftriaxone in rat serum was 1.08 μg/ml and 3.84 μg/ml, respectively. Similarly, the limit of detection and limit of quantification of ceftriaxone in CSF of rats was 0.94 μg/ml and 2.84 μg/ml, respectively. In both cases, the R2value was more than 0.99 and showed 99% accuracy.

Conclusion:

The experimental result suggests that the new RP-UFLC method developed and validated can be effectively used to assess ceftriaxone in preclinical studies in rats.

Performance indicators for a holistic evaluation of catalyst-based degradation-A case study of selected pharmaceuticals and personal care products (PPCPs)

Considerable efforts have been made to develop effective and sustainable catalysts, e.g., carbon-/biochar-based catalyst, for the decontamination of organic pollutants in water/wastewater. Most of the published studies evaluated the catalytic performance mainly upon degradation efficiency of parent compounds; however, comprehensive and field-relevant performance assessment is still in need. This review critically analysed the performance indicators for carbon-/biochar-based catalytic degradation from the perspectives of: (1) degradation of parent compounds, i.e., concentrations, kinetics, reactive oxidative species (ROS) analysis, and residual oxidant concentration; (2) formation of intermediates and by-products, i.e., intermediates analysis, evolution of inorganic ions, and total organic carbon (TOC); and (3) impact assessment of treated samples, i.e., toxicity evolution, disinfection effect, and biodegradability test. Five most frequently detected pharmaceuticals and personal care products (PPCPs) (sulfamethoxazole, carbamazepine, ibuprofen, diclofenac, and acetaminophen) were selected as a case study to articulate the performance indicators for a holistic evaluation of carbon-/biochar-based catalytic degradation. This review also encourages the development of alternative performance indicators to facilitate the rational design of catalysts in future studies.

HPLC methods for quantifying anticancer drugs in human samples: A systematic review

Pharmacokinetic (PK) study of anticancer drugs in cancer patients is highly crucial for dose selection and dosing intervals in clinical applications. Once an anticancer drug is administered, it undergoes various metabolic pathways; to determine these pathways, it is necessary to follow the administered drug in biological samples via different analytical methods. In addition, multi-drug quantification methods in patients undergoing multi-drug regimens of cancer therapy can have several benefits, such as reduced sampling time and analysis costs. In order to collect and categorize these studies, we conducted a systematic review of HPLC methods reported for the analysis of anticancer drugs in biological samples. A systematic search was performed on PubMed Medline, Scopus, and Web of Science databases, and 116 studies were included. In summary of included studies, when the objective of a method was to quantify a single drug, MS, or UV detectors were utilized equivalently. On the other hand, in methods with the aim of quantifying drug and metabolite(s) in a single run, MS detectors were the most utilized. This review can provide a comprehensive insight for researchers prior to developing a quantification method and selecting a detector.

Ultra high-performance liquid chromatography method development for separation of formoterol, budesonide, and related substances using an analytical quality by design approach

The application of the Quality by Design (QbD) principles in developing a new ultra high performance liquid chromatography method for the analysis of formoterol/budesonide and related substances using Fusion QbD® software is explored. The effect of various chromatographic parameters including, column stationary phase, pH, temperature, flow rate, and gradient time on separations were systematically investigated. Results show that optimal separations of these compounds in a standard solution can be achieved using a BEH C₁₈ column (2.1 × 1.7 μm × 10 cm) applying a pH of 8.2, a temperature of 35 °C, a flow rate of 0.35 mL min^-1 and a gradient time of 25 min. Furthermore, the results show that the main parameters affecting the performance of the method were the mobile phase pH, gradient time, and the temperature. For example, the most important factor for peak tailing was the pH of the mobile phase and the critical factors affecting resolution of the analytes were the gradient time and the temperature. As an application, the method was further used to analyze budesonide and formoterol in a sample obtained from a Symbicort® metered dose inhaler and it was found to provide similar separations to those obtained with the standard solution. These findings indicate that applying the QbD principles in analytical method development can be very advantageous not only in obtaining deep understanding of the effect of input parameters but also potential regulatory flexibility.

Miniature Multiwavelength Deep UV-LED-Based Absorption Detection System for Capillary LC

A new miniature deep UV absorbance detector has been developed using low-cost and high-performance LEDs, which can be operated in both scanning (230 to 300 nm) and individual wavelength (240, 255, and 275 nm) detection modes. The detector is mostly composed of off-the-shelf components, such as LEDs, trifurcated fiber optic assembly, a capillary Z-type flow cell, and photodiodes. It has been characterized for use with a standard capillary LC system and was benchmarked against a standard variable wavelength capillary LC detector. The detector shows very low levels of stray light (<0.4%), utilization of up to 99.0% of the effective path length of the flow cell, a wide dynamic range (0.5 to 200 μg/mL for sulfamethazine, carbamazepine, and flavone), and low noise levels (at 300 μAU level). The detector was applied within a miniaturized LC system.

UPLC-ESI/Q-TOF MS/MS Method for Determination of Vildagliptin and its Organic Impurities

Vildagliptin (VLG) corresponds to a drug used for the treatment of diabetes mellitus. This disease requires continuous treatment, and so the control of impurities present in it is important to assure the quality of this drug. Thus, it is necessary to use sensitive and selective detection techniques and the ultra-performance liquid chromatography is a better option compared with high-performance liquid chromatography because it enhances the separation efficiency with a shorter analysis time and an increased resolution. This research analysis was accomplished by using liquid chromatography/tandem mass spectrometry, and the quantification was performed by using an extracted ion from the VLG drug and its main organic impurities of synthesis. During the validation process, following international standards, the method proved to be linear for the tree substances (R2 = 0.997-0.998) and the analysis of variance showed a non-significant linearity deviation (P > 0.05). Three critical factors were selected to evaluate method robustness with a full factorial experimental design, and the changes in the parameters were found to be not significant for the quantification of VLG and its impurities. The ultra-performance liquid chromatography-tandem mass spectrometry for the determination of impurities in VLG was precise, accurate and robust proving to be effective for analysis in the pharmaceutical industry and to improve the quality, safety and effectiveness of the new drug developed.

Development of a RP-HPLC method for simultaneous determination of reference markers used for in-situ rat intestinal permeability studies

One of the most common techniques for assessing the intestinal absorption characteristics of drugs is single-pass intestinal perfusion (SPIP) method. Metoprolol tartrate (MT, reference standard) and phenol red (PR, zero permeability marker) are the compounds that are normally used in SPIP studies. The aim of this study was to develop a reverse phase high-performance liquid chromatography (RP-HPLC) method combined with UV-detection for the simultaneous determination of MT and PR in the perfusion medium used in SPIP experiments. Elution was performed using a Restek Raptor C18 column (5 μm, 4.6 mm × 250) at a temperature of 25 °C. The mixture of the mobile phase consisted of (MeOH):(Phosphate buffer solution, PBS), (20 mM, pH 3.0 adjusted with ortho-phosphoric acid),(55:45, v/v). Flow rate and column temperature were set at 1.2 mL min^-1 and 25 °C, respectively. MT and PR were injected as 20 µL into the HPLC system. UV detection was performed at 227 nm. The obtained retention times were reported as 2.89 and 3.80 min for MT and PR, respectively. The developed RP-HPLC method was validated according to Q2(R1) guideline of The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). The method was linear within the range of 2-50 μg mL^-1 for PR and 10-75 μg mL^-1 for MT. The developed RP-HPLC method was successfully applied on determination of MT and PR in perfusion medium. The developed method could be helpful for researchers working on in-situ rat intestinal permeability studies and it could be easily modified on further studies.

AutoTuner: High Fidelity and Robust Parameter Selection for Metabolomics Data Processing

Untargeted metabolomics experiments provide a snapshot of cellular metabolism but remain challenging to interpret due to the computational complexity involved in data processing and analysis. Prior to any interpretation, raw data must be processed to remove noise and to align mass-spectral peaks across samples. This step requires selection of dataset-specific parameters, as erroneous parameters can result in noise inflation. While several algorithms exist to automate parameter selection, each depends on gradient descent optimization functions. In contrast, our new parameter optimization algorithm, AutoTuner, obtains parameter estimates from raw data in a single step as opposed to many iterations. Here, we tested the accuracy and the run-time of AutoTuner in comparison to isotopologue parameter optimization (IPO), the most commonly used parameter selection tool, and compared the resulting parameters’ influence on the properties of feature tables after processing. We performed a Monte Carlo experiment to test the robustness of AutoTuner parameter selection and found that AutoTuner generated similar parameter estimates from random subsets of samples. We conclude that AutoTuner is a desirable alternative to existing tools, because it is scalable, highly robust, and very fast (∼100–1000× speed improvement from other algorithms going from days to minutes). AutoTuner is freely available as an R package through BioConductor.

pH-adjusted solvent extraction and reversed-phase HPLC quantification of isoflavones from soybean (Glycine max (L.) Merr.)

Soybeans, Glycine max (L.) Merr., are among the most important food crops worldwide. Isoflavones are major bioactive phytochemicals in soybeans, and have a variety of health benefits, including antioxidative, antiatherosclerotic, antiinflammatory, and weak estrogen-like effects. The isoflavone content and composition of soybeans vary according to the cultivar and the extraction solvent conditions. Therefore, we investigated the effects of three different solvent pHs (1.0, 5.5, and 10.0) on the isoflavone, total phenolic, and total flavonoid contents and antioxidant capacities of eight soybean cultivars developed in Korea. Twelve isoflavones in soybeans were efficiently separated and identified on a reversed-phase high-performance liquid chromatography (HPLC) system. The percentage distribution of isoflavones measured by HPLC in the eight soybean cultivars at various extraction pHs decreased as follows: malonyl isoflavones (67.2% to 81.3%) > isoflavone glucosides (16.2% to 29.0%; as nonacylated form) > acetyl isoflavones (1.6% to 5.9%). The highest contents of isoflavone glucosides, malonyl derivatives, and acetyl derivatives were extracted at solvent pHs of 10.0, 1.0, and 5.5, respectively. The solvent extraction at pH 1.0 yielded a lower total isoflavone content than those at pHs 5.5 and 10.0. However, the highest total phenolic and flavonoid contents were extracted from soybeans at pH 1.0. Soybeans extracted at pH 10.0 displayed the highest antioxidant capacities in the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical assay. Taken together, these results suggest that proper solvent pH adjustment is needed to maximize the extraction of targeted forms of isoflavones from soybeans. PRACTICAL APPLICATION: Soybeans contain a variety of bioactive compounds, including isoflavones, which function as antioxidants and weak phytoestrogens. Chemical and instrumental analyses can facilitate the selection of soybean cultivars with high amounts of isoflavones for soybean breeding and isoflavone-enriched product development. Proper solvent pH adjustment allows for the efficient extraction of high amounts of targeted isoflavone subgroups (acetyl and malonyl forms) from soybeans for functional food products.

Dietary Antioxidants in Coffee Leaves: Impact of Botanical Origin and Maturity on Chlorogenic Acids and Xanthones

Natural polyphenols are important dietary antioxidants that significantly benefit human health. Coffee and tea have been shown to largely contribute to the dietary intake of these antioxidants in several populations. More recently, the use of coffee leaves to produce tea has become a potential commercial target, therefore prompting studies on the quantification of polyphenols in coffee leaves. In this study a variety of coffee leaf species, at different development stages, were analyzed using ultra-high pressure liquid chromatography. The results demonstrate that both the botanical origin of the samples and their maturity influence significantly the concentration of the antioxidants; for total chlorogenic acids a two-fold difference was found between different species and up to a three-fold variation was observed between young and mature leaves. Furthermore, the range of concentrations of chlorogenic acids in young leaves (35.7–80.8 mg/g of dry matter) were found to be comparable to the one reported for green coffee beans. The results provide important data from which potential new commercial products can be developed.

Stability of extemporaneous sulfadiazine oral suspensions from commercially available tablets for treatment of congenital toxoplasmosis

OBJECTIVES

To determine the physicochemical and microbiological stability of sulfadiazine suspensions (100 mg/mL) in simple syrup (A) and sorbitol (B) formulations prepared from commercially available tablets.

METHODS

An ultra-performance liquid chromatographic assay was developed and validated to determine the chemical stability of sulfadiazine. Three samples were prepared and stored at 5 and 25 °C and assayed at 0, 7, 14 and 30 days. Physical parameters (appearance, pH, particle size and viscosity) were also monitored. Microbiological examination was performed through the suitable counting method.

RESULTS

The formulations presented a sulfadiazine concentration of around 95% at the beginning at both temperatures. There was some variation in pH, viscosity and particle size distribution over time. The samples met the pharmacopoeia criteria of microbiological quality over 30 days, but only sulfadiazine formulated in syrup stored at 25 °C was suitable for use after one week.

CONCLUSION

The sulfadiazine suspension in simple syrup was chosen as the most suitable formulation because it demonstrated stability for 14 days at room temperature, providing an alternative liquid dosage form of sulfadiazine for congenital toxoplasmosis treatment.

Mapping metabolome changes in Luffa aegyptiaca Mill fruits at different maturation stages via MS-based metabolomics and chemometrics

Introduction

Luffa aegyptiaca Mill, sponge gourd or Egyptian cucumber, is grown worldwide for its edible fruit consumed as a vegetable like cucumber. Unlike young fruit (YF), the fully mature ripened fruit (MF) is strongly fibrous and is used as a cleanser to make scrubbing bath sponges. YF undergoes a complex series of physiological and biochemical changes during fruit ripening. However, the chemical compositional differences between YF and MF in Luffa aegyptiaca have not been distinguished to date.

Objectives

Comprehensively compare the metabolites profile of YF and MF to give insight on how maturation stage affects chemical composition.

Methods

Mass-based metabolomics comprising GC/MS and UHPLC/MS were adopted in this study targeting its volatile and non-volatile metabolites coupled with chemometrics to rationalize for the differences.

Results

A total of 53 volatile metabolites were identified via headspace solid phase microextraction (SPME) comprising 66.2% aldehydes/furans, 51.6% alcohols, 38.2% ketones, 15.1% acids and 10.1% aromatics of which aldehydes/ furans were dominant at both fruit stages. Young fruit was in general more erniched in metabolites as revealed from UHPLC/MS and GC/MS analyses. The YF group encompassed higher levels of short chain alcohols (1-octen-3-ol) and aldehydes ((E)-2-hexenal and cucumber aldehyde) in addition to terpenoids (linalool). In contrast, fatty acids (octanoic acid) predominated MF specimens. UHPLC/MS analysis revealed for several oleanene triterpene glycosides as major secondary bioactive compounds, dihydroxy-oxo-oleanenoic acid glycoside found more abundant in YF versus MF as revealed from multivariate data analyses.

Conclusions

Our results reveal for the distinct metabolite changes in L. aegyptiaca fruit in its different stages and to rationalize for its different usage.

Determination of Probiotic Abilities and Lactic Acid Content of Pediococcus acidilactici

Background:

Probiotics are living microorganisms that have a healthy influence on a host.

Objective:

The aim of this study was to isolate a probiotic Pediococcus acidilactici strain from newborn faeces and develop and optimize a selective high-performance liquid chromatography method for the determination and validation of its lactic acid content and also evaluate some probiotic characteristics.

Methods:

Isolated strains were identified by the API 50 CH system and 16S rDNA gene sequence analysis and tested for antibiotic susceptibility, bile salt tolerance, low pH resistance, proteolytic, haemolytic activity, as well as the production of bacteriocin, hydrogen peroxide, and lactic acid. Antimicrobial activity of selected strain against standard test microorganisms was determined by the spot lawn method and the quantitation of lactic acid was carried out by high-performance liquid chromatography on a Rezex ROA organic acid (300x7.8 mm) analytical column.

Results:

P. acidilactici M7 strain was evaluated as a potential probiotic due to its ability to survive at low pH values or in the presence of pepsin, pancreatin, and bile salts. The lactic acid amount of strain was found in the range between 5.59-5.94 mg mL-1 by HPLC. M7 strain was also found to be resistant to vancomycin, had no bacteriocin, and hydrogen peroxide production and was able to inhibit the growth of P. aeruginosa and E. faecalis by its lactic acid content.

Conclusion:

This study explains a simple, selective, and fully validated procedure for the determination of lactic acid from probiotic bacteria.

Recent Advances on Drug Analyses Using Ultra Performance Liquid Chromatographic Techniques and their Application to the Biological Samples

Introduction:

Ultra-Performance Liquid Chromatographic (UPLC) method enables analyst to establish an analysis at higher pressure than High Performance Liquid Chromatographic (HPLC) method towards liquid chromatographic methods. UPLC method provides the opportunity to study a higher pressure compared to HPLC, and therefore smaller column in terms of particle size and internal diameter are generally used in drug analysis. The UPLC method has attracted gradually due to its advantages such as short analysis time, the small amount of waste reagents and the significant savings in the cost of their destruction process. In this review, the recent selected studies related to the UPLC method and its method validation are summarized. The drug analyses and the results of the studies which were investigated by UPLC method, with certain parameters from literature are presented.

Background:

Quantitative determination of drug active substances by High-Performance Liquid Chromatography (HPLC) from Liquid Chromatography (LC) methods has been carried out since the 1970's with the use of standard analytical LC methods. In today's conditions, rapid and very fast even ultra-fast, flow rates are achieved compared to conventional HPLC due to shortening analysis times, increasing method efficiency and resolution, reducing sample volume (and hence injection volume), reducing waste mobile phase. Using smaller particles, the speed and peak capacity are expanding to new limit and this technology is named as Ultra Performance Liquid Chromatography. In recent years, as a general trend in liquid chromatography, ultra-performance liquid chromatography has taken the place of HPLC methods. The time of analysis was for several minutes, now with a total analysis time of around 1-2 minutes. The benefits of transferring HPLC to UPLC are much better understood when considering the thousands of analyzes performed for each active substance, in order to reduce the cost of analytical laboratories where relevant analysis of drug active substances are performed without lowering the cost of research and development activities.

Methods:

The German Chemist Friedrich Ferdinand Runge, proposed the use of reactive impregnated filter paper for the identification of dyestuffs in 1855 and at that time the first chromatographic method in which a liquid mobile phase was used, was reviewed. Christian Friedrich Chönbein, who reported that the substances were dragged at different speeds in the filter paper due to capillary effect, was followed by the Russian botanist Mikhail S. Tswet, who planted studies on color pigment in 1906. Tswet observes the color separations of many plant pigments, such as chlorophyll and xanthophyll when he passes the plant pigment extract isolated from plant through the powder CaCO3 that he filled in the glass column. This method based on color separation gives the name of "chromatographie" chromatography by using the words "chroma" meaning "Latin" and "graphein" meaning writing.

Results and Conclusion:

Because the UPLC method can be run smoothly at higher pressures than the HPLC method, it offers the possibility of analyzing using much smaller column sizes and column diameters. Moreover, UPLC method has advantages, such as short analysis time, the small amount of waste reagents and the significant savings in the cost of their destruction process. The use of the UPLC method especially analyses in biological samples such as human plasma, brain sample, rat plasma, etc. increasingly time-consuming due to the fact that the analysis time is very short compared to the HPLC, because of the small amount of waste analytes and the considerable savings in their cost.

Transformation Products of Organic Contaminants and Residues-Overview of Current Simulation Methods

The formation of transformation products (TPs) from contaminants and residues is becoming an increasing focus of scientific community. All organic compounds can form different TPs, thus demonstrating the complexity and interdisciplinarity of this topic. The properties of TPs could stand in relation to the unchanged substance or be more harmful and persistent. To get important information about the generated TPs, methods are needed to simulate natural and manmade transformation processes. Current tools are based on metabolism studies, photochemical methods, electrochemical methods, and Fenton’s reagent. Finally, most transformation processes are based on redox reactions. This review aims to compare these methods for structurally different compounds. The groups of pesticides, pharmaceuticals, brominated flame retardants, and mycotoxins were selected as important residues/contaminants relating to their worldwide occurrence and impact to health, food, and environmental safety issues. Thus, there is an increasing need for investigation of transformation processes and identification of TPs by fast and reliable methods.

A Review on Liquid Chromatography-Tandem Mass Spectrometry Methods for Rapid Quantification of Oncology Drugs

In the last decade, the tremendous improvement in the sensitivity and also affordability of liquid chromatography-tandem mass spectrometry (LC-MS/MS) has revolutionized its application in pharmaceutical analysis, resulting in widespread employment of LC-MS/MS in determining pharmaceutical compounds, including anticancer drugs in pharmaceutical research and also industries. Currently, LC-MS/MS has been widely used to quantify small molecule oncology drugs in various biological matrices to support preclinical and clinical pharmacokinetic studies in R&D of oncology drugs. This mini-review article will describe the state-of-the-art LC-MS/MS and its application in rapid quantification of small molecule anticancer drugs. In addition, efforts have also been made in this review to address several key aspects in the development of rapid LC-MS/MS methods, including sample preparation, chromatographic separation, and matrix effect evaluation.

Analytical Methods for the Determination of Rosuvastatin in Pharmaceutical Formulations and Biological Fluids: A Critical Review

Rosuvastatin calcium (ROS), ( Figure 1 ) belongs to the "statins" group, which is the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. This drug is indicated for dyslipidemias treatment and can help to decrease the level of "bad cholesterol" and can consequently reduce the development of atherosclerosis and the risk of heart diseases. ROS was developed by Astra-Zeneca and it was approved in 2003 by the FDA in the United States. In 2015, under the trade name Crestor®, it was the fourth largest selling drug in the United States with sales above $5 billion. This study presents a literature review of analytical methods for the quantification of ROS in pharmaceutical preparations and biological fluids. The major analytical methods described in this study for ROS were spectrophotometry, high-performance liquid chromatography (HPLC) coupled to ultraviolet (UV) detection, and tandem mass spectrometry (LC-MS/MS).

Physicochemical Stability of Extemporaneously Prepared Oral Suspension of Fluconazole 50 mg/mL in SuspendIt™

Background

There is a lack of an age-appropriate formulation of fluconazole. The extemporaneous preparation of an oral suspension with an extended beyond-use-date may represent a good therapeutic alternative for the paediatric population.

Methods

A fluconazole 50 mg/mL oral suspension was prepared and evenly distributed into twenty amber plastic bottles: ten bottles were stored in controlled room temperature (25 °C) whereas the remainder ten bottles were stored in refrigerated temperature (5 °C). The physical characteristics (colour/appearance, odor, pH and density) and chemical characteristics [fluconazole concentration using Ultra High Performance Liquid Chromatography (UPLC)] of the oral suspension were tested at nine pre-determined time-points over a period of 182 days.

Results

The density, pH and mean concentration of the oral suspension did not change significantly. The recovery of fluconazole ranged from 92.67 % to 98.79 % (5 °C) and from 94.31 % to 100.02 % (25 °C), both within the specification limits.

Conclusions

A palatable, sugar-free formula was developed for fluconazole 50 mg/mL in the oral suspending vehicle SuspendIt™ to allow an easy and rapid extemporaneous preparation in the hospital setting. The beyond-use-date of the formula was determined using a valid, stability-indicating analytical method and it was concluded that the extemporaneously prepared oral suspension is stable for 6 months at refrigerated and controlled room temperature.

Development and validation of ultra-performance liquid chromatography method for the determination of meloxicam and its impurities in active pharmaceutical ingredients

The main objective was to develop a suitable and rapid ultra-performance liquid chromatography (UPLC) method for the quantitative determination of meloxicam and its impurities. Starting from data in literature, we calculated the new parameters to translate a high performance liquid chromatography method used for the analysis of meloxicam with its major degradation products to UPLC method, and then we switched on many trials to optimize and improve its analytical performance. Chromatographic separation was achieved on ACQUITY UPLC HSS-T3 (2.1×100mm, 1.8μm). The eluted compounds were monitored at 260nm and 350nm. The flow rate was set at 0.4mL/min, injection volume at 0.8μl, and the column oven temperature was maintained at 45°C. The developed method was validated according to the International Conference on Harmonisation (ICH) guidelines for specificity, linearity, accuracy, precision, robustness, quantification limit, detection limit; and then applied to stability study of meloxicam subjected to different ICH prescribed stress conditions (hydrolysis, oxidation, heat and photolysis). The results show that the new UPLC method enables separation of meloxicam from its impurities in only 5min with a total mobile phase consumption of 1.8mL. All impurities get separated with good peak shapes and resolution factor greater than 2. The new method indicates stability and proved to be specific, precise accurate with linear correlation between concentrations and peak areas, allowing gain of more than six times analysis and more than twenty times solvent consumption, so in cost. Therefore, it can be beneficial for pharmaceutical industrial output.