Current Pharmaceutical Analysis - Current Issue

Infrared and Raman spectroscopy have emerged as promising diagnostic tools for gastric and liver cancer, offering significant advantages over traditional histology and biomarker-based methods.

These spectroscopic techniques provide rapid and highly specific molecular fingerprinting with minimal sample preparation, enabling real-time diagnosis and preserving samples for further analysis. The integration of nanoparticles, particularly in surface-enhanced Raman spectroscopy, enhances the sensitivity and resolution of the method by amplifying signal strengths through localized surface plasmon resonances. This advancement facilitates the detection of subtle molecular changes associated with cancer, even at early stages.

Raman spectroscopy, a non-destructive technique, can differentiate between healthy and malignant cells, aiding in the diagnosis of various gastric cancer forms, including adenocarcinoma and gastrointestinal stromal tumors. Similarly, IR spectroscopy provides insights into the chemical composition of tissues, detecting molecular changes associated with cancer. For liver cancer, including hepatocellular carcinoma, these spectroscopic methods reveal biochemical alterations, facilitating early detection and characterization of the disease. This review explores the application of Raman and IR spectroscopy in diagnosing gastric and liver cancers, emphasizing their potential to enhance diagnostic accuracy and improve patient outcomes by identifying molecular changes linked to malignancies.

Overall, the integration of nanoparticles into spectroscopic techniques holds significant potential for improving the accuracy, speed, and efficacy of cancer diagnostics.

The current study examines the methodical Quality by Design (QbD) that facilitated the creation of an easy-to-use, quick, affordable, and stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) technique for the efficient analysis of aloe-emodin.

The chromatographic conditions were optimized with the Design Expert software 11.0 version, i.e., flow rate, buffer concentration, and column temperature.

The results of the linearity graph show R² = 0.9988. The LOQ was 0.07949 µg/mL and the LOD was 0.02623 µg/mL. According to ICH rules, the technique validation parameters were within the allowed range. Utilizing the Design Expert 11.0 version, the Box–Behnken design experimental design explains the relationships between flow rate, buffer concentration, and column temperature at three distinct levels. The responses were monitored: the retention time (Rt), tailing factor (Tf), and number of theoretical plates (NTPs).

The suggested approach was appropriate for quantitative determination and may be used in clinical pharmacokinetic investigations, biopharmaceutics, accredited testing laboratories, and quality control departments in enterprises.

Favipiravir is an antiviral drug having pyrazine group moiety. It is a reliable and an efficient green solvent, and a highly recoverable bio-sampling method is required for it. It is widely used in COVID-19 treatment for the prevention of the spread of viral infections in the body.

This proposed green solvent (ionic liquid)-based bioassay study aimed to quantify favipiravir in rat-dried blood spots using Dispersive Liquid-liquid Microextraction (IL-DLLME).

The proposed bioassay separation was achieved through an isocratic elution mode using a hybrid silica-based ODS column (250 × 4.6 mm; 5 µm), a column temperature of 25°C, an injection volume of 10 µL, a flow rate of 1.0 mL/min, and a detector wavelength set at 310 nm. The run time was less than 10 minutes. Mobile phase was delivered with acetonitrile, methanol, and 10 mM Na2HPO4 at pH 4.0 ± 0.5, (15: 20: 65, v/v/v). In a microtube, 50 mL of Ionic Liquid (IL), 500 µL of disperser ACN, 50 μL of 10% NaCl, and IS (20 ng mL-1) were added to perform the Dried Blood Spot (DBS) sample extraction methodology. The advantages of the proposed methodology have been found to include minimum hematocrit effect and an adequate blood volume for testing, easy transportation, and significant extraction recovery. The sample analysis has been carried out using HPLC-PDA with oseltamivir used as an internal standard.

We have investigated the important variables, i.e., salt concentration (10% NaCl, analyte recovery being higher) and disperser solvent [50μL of BMIHP plus 500 µL of ACN (v/v) yielding the highest recovery], in the extraction process. Extraction Recovery (ER) and Enrichment Factor (EF) were also evaluated using the IL-DLLME method. The calibration curve examined a range of 0.5-150 µg/mL, with a lower Limit of Quantification (LOQ) being 0.5 µg/mL in QC as well as calibration samples, respectively.

Significant bioanalytical validation has been performed and all the parameters have been evaluated systematically as per bioanalytical method validation protocols, i.e., US FDA-2018 guidelines. The following analytical parameters have been covered: standard curve, limit of quantification, range, recovery, stability, accuracy, precision, sensitivity, ER, EF, and selectivity. The developed bioassay method has been successfully applied in the pharmacokinetic studies of rats and successfully applied in bulk drugs.

Potentilla discolor Bge. is a plant extensively utilized in Traditional Chinese Medicine (TCMs). Nevertheless, our knowledge of the chemical components and metabolic complexities in its extracts is still quite limited.

The study aimed to thoroughly analyze the flavonoid metabolism in Potentilla discolor Bge. extracts and conduct a pharmacodynamic evaluation.

In this study, we investigated the metabolism of flavonoids in Potentilla discolor Bge. extracts using SD rats. The research adopted the strategy of “in vivo metabolism assessment, basic study of pharmacodynamics and preliminary evaluation of molecular docking” to systematically investigate the pharmacodynamic substances and targets of action of Potentilla discolor Bge.

The results of the study showed that the main metabolic forms of Potentilla discolor Bge. in vivo include hydroxylation, methylation, and glycosylation. Among them, luteolin in the total flavonoids of Potentilla discolor Bge. has the strongest antimicrobial and antioxidant ability. Outcomes of molecular docking experiments indicated that the glycosylated metabolite of luteolin had a significant advantage in acting with Glp-1 (Glucagon-like peptide-1).

The present study revealed the metabolic pathways of total flavonoids in Potentilla discolor Bge. It not only effectively screened out their pharmacodynamic substances and targets but also provided a theoretical basis for the application of TCMs into a systematic application and also provided ideas for the direction of drug optimization in the future. However, the sample range of this study is limited, and it generalizability needs to be investigated.

This study investigates the application of polyamidoamine (PAMAM) dendrimers as an innovative drug delivery approach for enhancing the pharmacokinetic profile of ursolic acid (UA), a pentacyclic triterpenoid with multifaceted therapeutic properties. UA, sourced from plants like Sanguisorba officinalis and Salvia officinalis, has been extensively studied for its pharmacological characteristics, including anti-inflammatory, antioxidant, and anti-diabetic properties, as recognized in Traditional Chinese Medicine (TCM). The clinical utility of UA is hampered by low bioavailability, which is attributed to its hydrophobic nature. To address this limitation, we explore the use of PAMAM dendrimers, known for their drug delivery potential.

The UA-PAMAM G0 dendrimers were synthesized with varying molar ratios. Characterization included size analysis, PDI, and zeta potential determination. FTIR confirmed the chemical structure. Male SD rats were acclimatized and administered UA control suspension and UA-G0 dendrimer complex orally. Blood samples were collected for pharmacokinetic analysis. The study obtained IAEC approval.

The UA-PAMAM G0 dendrimer complexes exhibited varying sizes based on molar ratios, with the 2:1 ratio showing significantly smaller dimensions. FTIR confirmed successful conjugation. In the pharmacokinetic study, the UA-G0 dendrimer complex demonstrated higher plasma concentrations than UA alone, as indicated by increased Cmax and AUC values. The results suggest enhanced oral delivery and bioavailability of UA in the dendrimer complex.

This study demonstrated the successful synthesis of UA-PAMAM G0 dendrimer complexes with size variations based on molar ratios. The pharmacokinetic analysis revealed improved plasma concentrations and bioavailability of UA in the dendrimer complex compared to UA alone. These findings highlight the potential of PAMAM dendrimers for enhancing the oral delivery of hydrophobic compounds like UA, bridging the gap between traditional herbal medicine and modern drug delivery strategies. Further research can explore the broader applications of such dendrimer complexes in drug delivery systems.

This paper aims to analyze the clinical distribution and drug resistance changes of Klebsiella pneumoniae (KPN) from 2017 to 2021 in the Beijing Hospital of Integrated Traditional Chinese and Western Medicine to provide a reference for the clinical rational use of antibiotics.

We collected Klebsiella pneumoniae isolated from various clinical specimens in 2017-2021, analyzed the isolation rate, specimen distribution, and department distribution characteristics during the five years, and statistically analyzed their drug sensitivity tests and multiple drug resistance. Zhuhai Deere DL-96 full-automatic microbial analyzer was used for bacterial identification and drug sensitivity tests. The drug sensitivity test was interpreted according to the standards recommended by the American Clinical and Laboratory Standards Institute (CLSI).

A total of 1057 strains of Klebsiella pneumoniae were identified between 2017 and 2021, with proportions of 18.6%, 15.7%, 15.4%, 15.1%, and 15.0% in each respective year. Specimen distribution included sputum (66.0%), urine (17.9%), throat swab (9.4%), secretion (2.4%), pus (0.7%), venous blood (0.6%), vaginal swab (0.4%), and other sources (2.6%). Distribution by the department revealed specimens originating from the respiratory department (21.2%), cardiology department (17.8%), neurology department (13.4%), oncology department (13.0%), nephrology department (12.2%), acupuncture department (10.1%), and other departments (12.3%). In terms of drug susceptibility testing, Klebsiella pneumoniae exhibited high resistance rates to ceftriaxone, cefotaxime, ceftazidime, and ampicillin/sulbactam, with rates of 50.8%, 46.8%, 46.3%, and 43.6% respectively. Conversely, resistance rates to minocycline, amikacin, imipenem, and meropenem were relatively low, at 8.6%, 16.5%, 8.5%, and 9.4% respectively. Resistance rates to cefepime/sulbactam and piperacillin/tazobactam were 29.9% and 28.9%, respectively, while cephalosporin resistance rates ranged from 36.1% to 50.8%. Regarding multidrug resistance, the detection rates of ESBL-producing Klebsiella pneumoniae were 8.2%, 10.9%, 4.5%, 10.6%, and 6.4% from 2017 to 2021, with an average detection rate of 7.9%. The detection rates of CR-Kp were 12.1%, 11.7%, 5.8%, 9.9%, and 8.9% respectively, averaging 9.6% over the five-year period.

The sputum specimen of Klebsiella pneumoniae exhibits the highest detection rate among specimen distributions, signifying its significance as a pathogenic bacterium in respiratory tract infections. Notably, the respiratory department demonstrates the highest detection rate, underscoring the necessity to enhance the monitoring and management of Klebsiella pneumoniae infections in respiratory patients. Over the past five years, our hospital has observed a decreasing trend in the overall drug resistance rate of Klebsiella pneumoniae to 17 antibiotics. While imipenem and meropenem exhibit minimal resistance rates, these carbapenem antibiotics serve as crucial agents for treating gram-negative bacilli, particularly in critically ill patients, and are thus not recommended as first-line choices for routine clinical use. Conversely, minocycline, amikacin, ceftazidime/sulbactam, and piperacillin/tazobactam showcase relatively low resistance rates, enabling their empirical use based on clinical experience. Combination therapy with other antibiotics is advised for amikacin. Conclusion: Nevertheless, cephalosporins display a relatively high resistance rate, necessitating a reduction in their clinical utilization. Regarding multidrug resistance, the detection of ESBLs-producing Klebsiella pneumoniae (KP) and Carbapenem-Resistant KP (CR-Kp) has exhibited a declining trend over the past three years. Despite this positive trend, the issue of multidrug resistance in Klebsiella pneumoniae remains severe, with instances of complete drug resistance reported. Clinicians are urged to judiciously administer antibiotics guided by drug sensitivity test results and resistance rate variations, restrict the use of broad-spectrum antibiotics, and manage the emergence and spread of ESBLs-producing and CR-Kp bacteria.

Azithromycin (AZT), an antimicrobial, despite having a monograph in official compendiums and some methods available in the literature, there is still a demand for eco-efficient methods, which include green analytical chemistry.

This study aimed to develop and validate a green spectrophotometric method for quantifying AZT tablets.

Purified water and ethanol (90:10, v/v) and sulfuric acid 20% as a diluent and reagent, respectively, quartz cubette and 482 nm were used. The Eco-Scale Assessment (ESA) tool was used to evaluate the greenness of the proposed analytical method.

The proposed method was linear (20-70 µg mL^-1 with a correlation coefficient of 0.9984), precise (RSD < 5%), selective by sample adjuvants, exact (100.46%), and robust against changes in acid proportion and wavelength. The ESA calculation was 85 points.

The proposed method can be classified as an excellent green alternative to quantify AZT in tablets, in accordance with ESA.

Quercetin is a flavanol that has demonstrated pharmaceutical properties such as anti-inflammatory, antioxidant, and anti-carcinogenic properties. However, parenteral formulations of quercetin are currently not in widespread use due to its poor aqueous solubility, fast metabolism, and low bioavailability.

This study aimed to develop a quick, simple, and accurate method for the quantification of quercetin using ultra-fast liquid chromatography-tandem mass spectrometry (LC-MS/MS).

A rapid and sensitive LC-MS/MS method was developed and fully validated for the quantification of quercetin in rat plasma after intravenous administration. Quercetin reference standard was used for the method development as well as in-vivo validation. ACQUITY UPLC BEH C18 Column (2.1 x 50 mm, 1.7 µm) was used for the chromatographic separation. The mobile phase consisted of solution A (water with 0.1% formic acid) and solution B (methanol: acetonitrile with 0.1% formic acid in the ratio of 1:1) with a flow rate of 0.350 µL/min. Further, the method was applied to quantify and pharmacokineticly profile quercetin in the blood plasma of outbred male and female Wistar rats.

The accuracy of the method was calculated for intraday and inter-day, which came out as ≤ 85.23% and 84.87%, respectively. The precision of the method calculated for intraday was ≤3.02%, and for inter-day was ≤2.75%. The percentage recovery was found to be ≤85.23% for intraday and ≤84.87% for inter-day. The Relative Standard Deviation was 0.04 for intraday and 1.10 for inter day, respectively.

The developed method has an advantage over other reported methods because of its short run time of 6 minutes as well as its short time of data registration of approximately 2.5 minutes. This method can be used for the routine analysis of quercetin in vivo animal studies.

Antiretroviral medications are widely used to treat HIV infections. Lamivudine (3TC) is prescribed for HIV-1 infection management in adults and pediatrics, while valganciclovir (VGC) is a prodrug of ganciclovir derived from valine.

The Biopharmaceutics Classification System (BCS) estimates the contributions of intestinal permeability, dissolution, and solubility in oral drug absorption. Intestinal permeability refers to a substance's capacity to pass through the protective layer of cells in the intestine. The intestinal permeability of 3TC and VGC was analyzed and categorized using the single-pass intestinal perfusion technique according to the BCS in male Sprague Dawley rats, and a reversed-phase HPLC method was validated for precise and accurate measurement.

According to the BCS, 3TC and VGC have been classified as having low permeability when compared to metoprolol tartrate, which is classified as Class I with good permeability and resolution.

The permeability values derived from this work can be valuable in exposure assessment models.

S. barbata D. Don, a perennial herb from the Lamiaceae family, is renowned for its medicinal properties, with scutellarin and scutellarein being key bioactive constituents.

In this study, we present the development and validation of a High-Performance Thin-Layer Chromatography (HPTLC) method for the simultaneous quantitative and qualitative analysis of scutellarin and scutellarein in the hydroethanol extract of S. barbata D. Don.

The chromatographic conditions were optimized using different solvent systems, and validation was performed as per ICH guidelines.

The mobile phase comprising Ethyl acetate: methanol: formic acid: water (20: 2.7: 0.5: 2) and scanning wavelength set at 254 nm was optimized for study, resulting in distinct and well-separated spots for scutellarin and scutellarein with Rf values of 0.31 and 0.96, respectively. The method was rigorously validated to ensure reliability and reproducibility. Calibration curves exhibited excellent linearity for both scutellarin (r² > 0.98) and scutellarein (r² > 0.99) over a concentration range of 10-30 µg/ml. The developed method underwent thorough validation following ICH guidelines. Validation parameters included accuracy, limit of quantification, limit of detection, linearity, precision, and recovery. The determined concentration of scutellarin and scutellarein in the hydroethanolic extract of S. barbata D. Don was found to be 27.00 µg/mg and 20.16 µg/mg of extract, respectively.

This proposed method demonstrates its utility for both qualitative and quantitative analyses of scutellarin and scutellarein in the hydroethanolic extract of S. barbata D. Don, offering a reliable and validated approach for quality control and standardization in the herbal product industry.

Considerable interest has been devoted to electrochemical sensors for the detection of L-cysteine using BiPr-based oxide-modified electrodes due to high specific surface area and good electro-catalytic activity with several oxidation states. The combination of the BiPr composite oxide nanowires with polyaniline (PAn) can promote the electro-catalytic performance towards L-cysteine because PAn can facilitate the electro-catalytic process by enhancing the charge transfer.

PAn/BiPr composite oxide nanowires were obtained via low temperature one-step hydrothermal route. The obtained composite oxide nanowires were analyzed by X-ray diffraction, electron microscopy, and electrochemical methods.

Characterization results indicate that amorphous PAn nanoparticles with a size of about 50 nm are homogeneously dispersed at the surface of the BiPr composite oxide nanowires. PAn/BiPr composite oxide nanowire-modified electrode shows an enhanced L-cysteine electro-catalytic activity. PAn promotes electro-catalytic activity of the BiPr composite oxide nanowires. A pair of quasi-reversible cyclic voltammetry (CV) peaks exist at +0.49 V, -0.19 V, respectively. PAn/BiPr composite oxide nanowire modified electrode possesses a linear response in L-cysteine concentration of 0.001-2 mM and detection limit of 0.095 μM, good repeatability, and stability.

PAn/BiPr composite oxide nanowires act as effective electro-catalysts for L-cysteine oxidation resulting in the enhancement of the electro-catalytic activity relative to BiPr composite oxide nanowires.

Preservatives called parabens are frequently found in medicinal formulations and personal hygiene products. However, questions have been raised concerning their possible impact on health, leading to the need for reliable methods to determine their presence and degradation of products.

This study aimed to create and validate a straightforward, accurate, dependable, and selective method for determining the levels of methyl and propyl parabens, as well as the breakdown product p-hydroxy benzoic acid. Additionally, a force degradation study was conducted to assess the stability of parabens in a parenteral formulation under various conditions.

Separation of the compounds was achieved using X-Bridge C18 (250 X 4.6 mm) 5µm column with a mobile phase composed of water (pH 3.0 with glacial acetic acid) and methanol (30:70). Detection was carried out at 254 nm using a UV detector with an injection volume of 20 µL and a flow rate of 1.0 mL/min. Force degradation studies included acid, base, oxidation, thermal, and photo-degradation.

Under the described conditions, the separation of p-hydroxy benzoic acid, methylparaben, and propylparaben was achieved in less than 12.0 minutes. The concentration ranges for p-hydroxy benzoic acid, methylparaben, and propylparaben were determined to be 1ng - 50 µg/mL, 100ng - 50µg/mL, and 100ng -12µ g/mL, respectively. The linearity, accuracy, and precision of the method were within acceptable ranges.

Maximum degradation of methylparaben was observed under base and neutral conditions in the first sample and under base and thermal conditions in the second sample. Similarly, maximum degradation of propylparaben was observed under base conditions in the first sample and under neutral and thermal conditions in the second sample. P-hydroxy benzoic acid degradation was observed under all conditions, with the highest degradation occurring in 0.1 N NaOH and 0.1 N HCl at 60°C.

The developed method proved to be effective for the determination of methyl and propylparaben, along with their degradation product p-hydroxy benzoic acid, in pharmaceutical formulations. The results of the force degradation study provided valuable insights into the stability of parabens under various conditions, highlighting the importance of monitoring and controlling their degradation in pharmaceutical products.

Difenidol is widely used in clinical practice due to its good anti-dizziness effect and low side effect rate. This aim was to develop an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the selective and straightforward measurement of diphenidol in mouse plasma.

A total of eighteen mice were divided into three groups: six for intravenous administration at a dose of 0.2 mg/kg, six for oral administration at a dose of 0.4 mg/kg, and another six for oral administration at a dose of 1.6 mg/kg. The analytes were extracted using acetonitrile-mediated protein precipitation following the addition of the internal standard (IS), midazolam. On an Acquity HSS T3 column (50 mm × 2.1 mm, 1.8 μm). The quantification process involved the use of multiple reactions monitoring (MRM) mode, with target fragment ions m/z 310.2→128.9 for diphenidol and m/z 326.2→291.4 for IS.

For diphenidol, calibration curves showed a linear distribution between 0.2 and 50 ng/mL. The accuracy of the method was between 94.6% and 110.4%, and the mean recovery of diphenidol in mouse plasma was over 76.5%. The intra-day and inter-day precision RSDs were both limited to 14%. The bioavailability of diphenidol in mice was determined to be 19.9% and 23.56% for the oral dose of 0.4 mg/kg and 1.6 mg/kg, respectively.

The UPLC-MS/MS was successfully applied to study the pharmacokinetics of diphenidol in mice, to which it was administered orally and intravenously.