High-performance Liquid Chromatography Results Research Articles

Evaluation of Gentamicin Release of PMMA Cements Using Different Methods: HPLC, Elution and Inhibition Zone Testing.

(1) Background: There is an ongoing discussion on the elution efficacy of antibiotic-impregnated cements. Our experiments were intended to clarify if there are differences in the antibiotic elution of HPLC compared with inhibition zone testing using eluates or PMMA discs. (2) Materials and Methods: Two cement brands with different concentrations of the active ingredient were tested in antimicrobial Kirby-Bauer (disc diffusion) assays. Cement platelets were directly applied on the agar plates and their zone of inhibition was measured. In parallel, the platelets were incubated in phosphate buffered saline (PBS) and at distinct points of time transferred into new buffer. At these time points, 50 µL of the bone cement eluates was used for zone of inhibition testing. Standard gentamicin sulfate solutions served as a control in the same test setup. To verify the microbiological investigations, the antibiotic content of the eluates was also measured via high-performance liquid chromatography (HPLC). (3) Results: The experiments with cement eluates showed better differentiable results than the direct application of the cement discs. The results were also comparable to investigations with HPLC and gentamicin sulfate standard solutions. (4) Conclusions: The results of elution rates are influenced by the test system and the period of observation chosen. The microbial test systems reflect the results of HPLC to the same degree and give evidence of the efficacy of the antibiotics. The HPLC tests on eluates were more suitable in representing differences in release characteristics.

Investigation of quality control of Gastrodia elata using electrochemical fingerprint technology

Gastrodia elata, a traditional Chinese medicinal herb, undergoes processing with ginger to enhance its therapeutic properties. This study investigated the impact of ginger processing on the quality control of G. elata using electrochemical fingerprint technology and high-performance liquid chromatography (HPLC). The electrochemical fingerprint conditions were optimized, and the fingerprints of raw and ginger-processed G. elata samples were compared. The HPLC analysis revealed significant changes in the contents of gastrodin, parishin A, and parishin B after processing. The electrochemical fingerprints exhibited distinct differences between raw and ginger-processed samples, with improved batch-to-batch consistency in the latter. Principal component analysis and hierarchical cluster analysis demonstrated the correlation between the electrochemical fingerprints and HPLC results. The findings highlight the potential of electrochemical fingerprint technology as a complementary tool to HPLC for the comprehensive quality assessment of G. elata. This study provides valuable insights into establishing standardized processing protocols and quality control strategies for G. elata, emphasizing the importance of combining multiple analytical techniques for ensuring the consistency, safety, and efficacy of herbal medicines.

Enhanced Dissolution and Bioavailability of Curcumin Nanocrystals Prepared by Hot Melt Extrusion Technology.

Curcumin nanocrystals (Cur-NCs) were prepared by hot melt extrusion (HME) technology to improve the dissolution and bioavailability of curcumin (Cur). Cur-NCs with different drug-carrier ratios were prepared by one-step extrusion process with Eudragit® EPO (EEP) as the carrier. The dispersed size and solid state of Cur in extruded samples were characterized by dynamic light scattering (DLS), scanning electron microscope (SEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The thermal stability of Cur was analyzed by thermogravimetric analysis (TGA) and high performance liquid chromatography (HPLC). Dissolution and pharmacokinetics were studied to evaluate the improvement of dissolution and absorption of Cur by nano-preparation. Cur-NCs with particle sizes in the range of 50~150 nm were successfully prepared by using drug-carrier ratios of 1:1, 2:1 and 4:1, and the crystal form of Cur was Form 1 both before and after HME. The extrudate powders showed very efficient dissolution with the cumulative dissolution percentage of 80% in less than 2 min, and the intrinsic dissolution rates of them were 13.68 ± 1.20 mg/min/cm2, 11.78 ± 0.57 mg/min/cm2 and 4.35 ± 0.20 mg/min/cm2, respectively, whereas that of pure Cur was only 0.04 ± 0.00 mg/min/cm2. The TGA data demonstrated that the degradation temperature of Cur was about 250 °C, while the HPLC results showed Cur was degraded when extruded at the temperature over 150 °C. Pharmacokinetic experiment showed a significant improvement in the absorption of Cur. The Cmax of Cur in the Cur-NC group was 1.68 times that of pure Cur group, and the Cmax and area under the curve (AUC0-∞) of metabolites were 2.79 and 4.07 times compared with pure Cur group. Cur-NCs can be prepared by HME technology in one step, which significantly improves the dissolution and bioavailability of Cur. Such a novel method for preparing insoluble drug nanocrystals has broad application prospects.

Validation of HPLC and TLC analytical methods to determine radiochemical purity of 99mTc-cAbVCAM1-5, a new experimental radiotracer

Cardiovascular diseases, including fatal myocardial infarctions from atheromatous plaques, are the primary global mortality cause. Detecting stenotic atheromatous plaques is possible through coronary angiography, but vulnerable plaques with eccentric remodeling are undetectable with current diagnostic methods. Addressing this challenge, our group developed a radiopharmaceutical drug targeting vascular cell adhesion molecule 1 (VCAM-1), radiolabeled with technetium-99m. Given the absence of a monograph in the European Pharmacopoeia, and in order to draft the investigational medicinal product documentation, analytical methods had to be validated by high performance liquid chromatography (HPLC) and thin layer chromatography (TLC) to determine the radiochemical purity (RCP) of 99mTc-cAbVCAM1–5. This study therefore presents the results of the validation of analytical methods obtained in this context. The method validation followed the European Association of Nuclear Medicine (EANM) recommendations adapted from ICH Q2(R1), ensuring conformity with specificity, accuracy, repeatability and intermediate precision, linearity, robustness, quantification limit (LoQ), and range criteria. Regarding the results of specificity, both HPLC and TLC methods demonstrated excellent separation of 99mTc-cAbVCAM1–5 from impurities 99mTcO4-. Accuracy results indicated recovery percentages within the range of 99.52–101.40% for the HPLC and 99.51–101.97% for TLC, ensuring reliable measurements for each concentration of 99mTcO4-. Precision of the methods was validated by assessing repeatability and intermediate precision. Linearity was determined over the usual concentrations range and the correlation coefficient was greater than 0.99 for both methods. The limit of quantification was measured by diluting the 99mTcO4- to obtain a signal-to-noise ratio of around 10:1. Under these conditions, we obtained an LOQ of 2.10 MBq/mL for HPLC and 2Mbq/mL for TLC. In conclusion, the analytical methods developed in this study comply with EANM recommendations. This therefore allows us to correctly assess the radiochemical purity of 99mTc-cAbVCAM1–5, a new radiotracer targeting inflammation in vulnerable plaques.

Mycoremediation Approach to Green Air: Phenanthrene and Anthracene Degrading Ability by Fusarium solani Isolate P11M-46

There are many health issues associated with air pollution that are rapidly increasing with time across the globe. Among many air pollutants, polycyclic aromatic hydrocarbons (PAHs) are of particular concern because of their carcinogenicity, genotoxicity, and long persistence in the environment. The majority of these PAHs release into the air through anthropogenic activities and natural sources. After releasing into the air, PAHs usually return to the ground due to their high molecular weight. These hydrocarbon depositions can be categorized as wet or dry depositions. One of the most prominent deposition surfaces of these pollutants is the phyllosphere. Microorganisms such as fungi perform a key role in PAHs elimination through bioremediation processes. Epiphytic fungi such as Fusarium solani isolate P11M-46 utilizes the deposited phenanthrene and anthracene on the phyllosphere and convert those PAHs in to non-toxic levels. The aim of this study was to evaluate the ability of F. solani isolate P11M-46 to degrade phenanthrene and anthracene, through a mycoremediation approach. Leaf samples were collected from Panchikawatta, Orugodawatta, Pettah, Maradana, Colombo Fort, and Sapugaskanda urban areas in Sri Lanka. Furthermore, PAH degradation ability of isolated F. solani isolate P11M-46 was confirmed through High Performance Liquid Chromatography (HPLC). The effects of by-products produced from the biodegradation process on living beings were evaluated using Artemia salina and the by-products were identified using Gas Chromatography and Mass Spectrometry (GCMS). According to HPLC results, F. solani isolate P11M-46 showed 68% of degradation percentage in phenanthrene while exhibiting 76% degradation in anthracene within 6 days. The GCMS analysis confirmed that the by-products were Phenol, 2-(phenylmethyl) from phenanthrene and 9, 10-anthracenedione from anthracene. Toxicity assay with A. salina confirmed that these byproducts were not toxic to the phyllosphere. The findings of the present study revealed the potential use of phyllosphere F. solani isolate P11M-46 in the remediation of environmental pollutants phenanthrene and anthracene. And also the by-products produced during their degradation mechanism were also confirmed as nontoxic compounds. Therefore, F. solani isolate P11M-46 could be effectively used in the bioremediation of phenanthrene and anthracene in polluted environments as a bioremediator. 
 Keywords: Polycyclic aromatic hydrocarbons, Bioremediation, HPLC, GCMS, Toxicity

MALDI-MS in first-line screening of newborns for sickle cell disease: results from a prospective study in comparison to HPLC.

Newborn screening (NBS) for sickle cell disease (SCD) requires a robust, high-throughput method to detect hemoglobin S (HbS). Screening for SCD is performed by qualitative methods, such as isoelectric focusing (IEF), and both qualitative and quantitative methods such as high performance liquid chromatography (HPLC), capillary electrophoresis (CE), and tandem mass spectrometry (MS/MS). All these methods detect HbS, as well as low-level or absent HbA, and also other variants of hemoglobin. HPLC is considered as a reference method for NBS, because of its high sensitivity and specificity in detecting HbS. NeoSickle®, a fully automated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) platform, combined with automated sample processing, a laboratory information management system and NeoSickle® software for automatic data interpretation, has increased the throughput of SCD testing. The purpose of this study was to compare the performances of NeoSickle® and HPLC. A prospective study was conducted including 9,571 samples from the NBS program to compare MALDI-MS using NeoSickle® with an HPLC method. Correlation between the two methods was studied. For the MALDI-MS method, sensitivity, specificity, NPV, and PPV were calculated. We found over 99.4 % correlation between the HPLC and MALDI-MS results. NeoSickle® showed 100 % of sensitivity and specificity in detecting SCD syndrome, leading to positive and negative predictive values of 100 %. NeoSickle® is adapted to NBS for SCD, and can be used in first-line high-throughput screening to detect HbS, and beta-thalassemia major warning. When HbS is detected, second-line use of another specific method as HPLC is necessary.

Study of Quality Standards of Xiao’er Qingre Enema Preparation in Hospitals

Objective: To establish the quality standards for the preparation of Xiao’er Qingre enema in hospitals. Method:Thin-layer chromatography (TLC) was used to identify Radix Isatidis and Glycyrrhizae in the prescription. The content of (R,S)-Goitrin was determined by high-performance liquid chromatography (HPLC). Results: In TLC identification, there was no interference between the negative controls of Radix Isatidis and glycyrrhizae, and the spots were well-separated. The HPLC results of (R,S)-Goitrin showed a good linear relationship between the peak area and concentration within the range of 0.476–95.2 μg·mL-1 (r = 0.9999). Conclusion: The TLC and HPLC methods established in this experiment are simple, reproducible, and specific, making them suitable for the quality control Xiao’er Qingre enema preparation in hospitals.

Extraction, Isolation and Structure Elucidation of Two Phenolic Acids from Aerial Parts of Celery and Coriander

Celery and coriander are vastly applied in modern medicine and traditionally because various medicinal and nutritional benefits depend on their medicinal characteristics. The study aimed to detect, isolate and compare extracts contents of phenolic acids (caffeic and p-coumaric acids) in ethyl acetate fraction of fresh and dry aerial parts of coriander (Coriandrum sativum L.) and celery (Apium graveolens L.) of the Apiaceae family. The extraction of these constituents was carried out by maceration method using 70% ethanol and fractionation was done by using petroleum ether, and ethyl acetate. The existence of caffeic and p-coumaric acids in aerial part extracts of two plants was identified by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). After qualitative determination of these active constituents, high-performance liquid chromatography analysis was also applied for quantification of caffeic and p-coumaric acid and the results showed that ethyl acetate extract of dry coriander showed higher contents of caffeic and p-coumaric acid than ethyl acetate extracts of fresh coriander and celery (dry and fresh). Depending on the results of TLC and HPLC, two bioactive compounds (caffeic acid and p-coumaric acid) were isolated and identified by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and full scan product ion mode liquid chromatography mass spectrometry. This result opens the minds to the dry plant era and leads to counter fiction of what was known that fresh plant gives better results than the dry one.

Influence of Galvanic Interaction between the Iron Grinding Medium and Chalcopyrite on Collectorless Flotation Behavior of Chalcopyrite: Experimental and Density Functional Theory Study.

The eco-friendly flotation process for chalcopyrite is economically significant and promotes sustainable development in mining. Collectorless flotation is a green and clean method for chalcopyrite utilization, but galvanic interactions during the grinding process can affect the surface structure, chemical composition, and electrochemical properties, impacting collectorless flotation recovery. This article uses a self-made device and flotation experiments to study galvanic interactions and their effects on surface oxidation and collectorless flotation behavior under different grinding conditions (including mineral particle size, slurry water content, pressure, and galvanic interaction time). The impact of galvanic interaction on the surface chemical composition and electrochemical properties of chalcopyrite is studied using high-performance liquid chromatography (HPLC), X-ray photoelectron spectroscopy (XPS), and electrochemical tests. Additionally, the effect of the galvanic interaction on the surface structure is analyzed with density functional theory. XPS and HPLC results show that iron grinding media contact with chalcopyrite, reducing elemental sulfur content of the chalcopyrite surface, improving hydrophilicity, and decreasing chalcopyrite collectorless flotation recovery. Grinding conditions, such as mineral particle size, slurry water content, and galvanic interaction time, significantly impact collectorless flotation and can be regulated to optimize results.

Differential sensitivity to hypoxia enables shape-based classification of sickle cell disease and trait blood samples at point of care.

Red blood cells (RBCs) become sickle-shaped and stiff under hypoxia as a consequence of hemoglobin (Hb) polymerization in sickle cell anemia. Distinguishing between sickle cell disease and trait is crucial during the diagnosis of sickle cell disease. While genetic analysis or high-performance liquid chromatography (HPLC) can accurately differentiate between these two genotypes, these tests are unsuitable for field use. Here, we report a novel microscopy-based diagnostic test called ShapeDx™ to distinguish between disease and trait blood in less than 1 h. This is achieved by mixing an unknown blood sample with low and high concentrations of a chemical oxygen scavenger and thereby subjecting the blood to slow and fast hypoxia, respectively. The different rates of Hb polymerization resulting from slow and fast hypoxia lead to two distinct RBC shape distributions in the same blood sample, which allows us to identify it as healthy, trait, or disease. The controlled hypoxic environment necessary for differential Hb polymerization is generated using an imaging microchamber, which also reduces the sickling time of trait blood from several hours to just 30 min. In a single-blinded proof-of-concept study conducted on a small cohort of clinical samples, the results of the ShapeDx™ test were 100% concordant with HPLC results. Additionally, our field studies have demonstrated that ShapeDx™ is the first reported microscopy test capable of distinguishing between sickle cell disease and trait samples in resource-limited settings with the same accuracy as a gold standard test.

A Novel, Rapid, and Accurate Quantitative Hydroxyurea Assay

Introduction: Hydroxyurea is a highly effective treatment for children and adults with sickle cell anemia (SCA) and is now considered standard-of-care therapy in high-resource countries. There is wide interpatient variability in the optimal dose, which is defined as the daily dose that provides maximal induction of protective fetal hemoglobin to decrease erythrocyte sickling while causing only mild marrow suppression. The time and cost of hydroxyurea dose titration are barriers to its widespread use in low-resource settings. The titration process required to identify an optimal dose can be abbreviated by measuring individualized hydroxyurea pharmacokinetics (PK) to guide personalized precision dosing, which could be especially useful in low-resources settings with limited laboratory monitoring. However, measurement of hydroxyurea in serum and other physiological fluids is not commonly performed during routine clinical treatment. Current methodology to quantify hydroxyurea concentrations requires complex and time-consuming chemical derivatization followed by detection by colorimetric spectrophotometry, high performance liquid chromatography (HPLC), or liquid chromatography mass spectrometry (LC-MS). To consider performing PK-guided dosing in low-resource settings, a simple, accurate, and efficient hydroxyurea assay is needed. Methods: A commercially available open-system HPLC unit for hemoglobin separation (SmartLifeLC, PolyLC Inc, Columbia MD) was equipped with a 3.5-micron, 4.6 mm × 50 mm Zorbax Eclipse XDB-C18 column with matching guard column (Agilent Technologies, Santa Clara, CA); mobile phases of 46% methanol and 100% acetonitrile; and a 200-600nm multi-wavelength detector. The chemical derivatization process was modified from previously published techniques that use xanthydrol (Sigma-Aldrich, St. Louis MO) for detection of primary amides. N-methylurea (Sigma-Aldrich) was included as an internal standard. Hydroxyurea (Sigma-Aldrich) was diluted in whole blood collected from healthy controls to create a calibration curve encompassing the typical pharmacological range of hydroxyurea at 80, 40, 20, 10, and 5 mg/mL. Quality Control (QC) samples were prepared at 50, 25, 12.5, and 6.25 mg/mL to validate the calibration curve before testing patient samples. Blood was applied to 20mL volumetric absorptive microsampling devices (Mitra, Trajan Scientific and Medical, Torrance CA) and dried for future elution and analysis. HPLC results were compared to LC-MS results to assess accuracy. Results: Blood was eluted from the Mitra microsampling device and derivatized in a xanthydrol solution before HPLC analysis. Using a 10-minute run with 210nm wavelength detection, the xanthydrol-modified hydroxyurea reproducibly yielded a linear calibration curve with r 2 >0.95 (Figure), and the actual concentrations were within 20% of the theoretical values. Repeated testing of control and patient samples revealed a typical intra-day coefficient of variation <15% and inter-day coefficient of variation <20%. The agreement between nominal values and assay results determined for a wide range of QC samples from both methods exceeded the FDA-recommended threshold of 67% for chromatographic assay validation with 86% agreement on LC-MS and 85% with the new method. The entire elution and derivatization procedure could be completed using dried Mitra blood samples in less than 60 minutes. Conclusions: Quantitative hydroxyurea measurement of blood or serum can now be accomplished using a novel, rapid, HPLC technique that features xanthydrol-based derivatization of hydroxyurea, an internal standard, and UV wavelength detection. This technique is accurate, reproducible, and relatively simple, and thus deemed suitable for hydroxyurea concentration measurements needed for PK-guided dosing calculations for children with SCA living in low-resource settings. This novel technique will be added to the multi-country Realizing Effectiveness Across Continents with Hydroxyurea (REACH, NCT01966731) trial that will feature PK-guided precision dosing for young children with SCA starting hydroxyurea treatment.

A strategy takes “Yiqing” tablets as an example to carry out simpler multi-component quantification and use fingerprint technology for comprehensive quality consistency evaluation

The comprehensive evaluation of the quality of traditional Chinese medicines (TCM) is an important issue for the continuous progress and exploration of TCM. In this study, a “Yiqing” tablet (YQT) was taken as an example, and the sample quality was comprehensively investigated by multi-component quantification, multi-dimensional fingerprint construction, and antioxidant activity analysis. Based on high performance liquid chromatography (HPLC) and fourier transform infrared spectroscopy (FTIR) fingerprint, accurate and fast multi-component quantification is achieved by reliable Multi-markers assay by mono-linear method (MAML) method and verified partial least squares regression (PLSR) model. The basic HPLC fingerprint and the special FTIR quantitative fingerprint were evaluated by SQFM, and the rich fingerprint qualitative and quantitative information of the sample was obtained. The characteristic parameter (blocking rate (BR)) characterizing antioxidant activity in the electrochemical (EC) fingerprint was excavated for the first time, and the fingerprint-efficacy analysis results with HPLC and FTIR were obtained through bivariate correlation analysis (BCA). The results showed that 25 components in the HPLC fingerprint and had antioxidant activity, and most bands of FTIR showed antioxidant activity. Finally, by combining the evaluation results of HPLC and FTIR fingerprint using the mean method, all samples were classified as first level, except for S1, demonstrating the consistency of sample quality. Based on the comprehensive quality evaluation system combining vertical and horizontal combination, this study provides a new idea for achieving comprehensive quality evaluation of TCM.

The Significance of System Suitability in High-Performance Liquid Chromatography (HPLC) Analysis: Ensuring Accurate and Reliable Results

High-Performance Liquid Chromatography (HPLC) has emerged as a fundamental technique in modern analytical chemistry, serving as a powerful tool for the separation, identification, and quantification of [1] diverse compounds. One critical aspect that ensures the validity and credibility of HPLC results is the concept of system suitability. This abstract highlights the importance of system suitability in HPLC analysis, emphasizing its role in ensuring accurate and reliable results. System suitability is a set of pre-defined criteria that evaluate the performance of the HPLCsystem, encompassing factors such as resolution, peak symmetry, tailing factor, retention time, and peak area reproducibility. Adhering to these criteria is essential for consistent and precise analyses, as they confirm that the instrument is operating optimally and capable of generating dependable data

The blood count as a compass to navigate in the ever-changing landscape of the carrier state of hemoglobinopathies: a single-center Italian experience.

Approximately 7% of the worldwide population exhibits variations in the globin genes. The recent migration of populations from countries where hemoglobin disorders are endemic has resulted in important epidemiological changes with the diffusion of newly discovered or poorly characterized genetic variants and new combinations and very heterogeneous clinical phenotypes. The aim of our study is to assess the parameters that are more significant in predicting a positive genetic testing outcome for hemoglobinopathies in a pediatric population of patients presenting with anemia or microcythemia, without a definite diagnosis. This study included patients evaluated in our hematological outpatient clinic for anemia and/or microcythemia despite normal ferritin levels. A screening of pathological hemoglobins using high-performance liquid chromatography (HPLC) was performed for the entire population of the study. Subsequently, patients with hemoglobin (Hb) S trait and patients with an HPLC profile compatible with beta thalassemia trait were excluded from the study. Genetic screening tests for hemoglobinopathies were performed on the remaining patients, which involved measuring the red blood cell (RBC) counts, red blood cells distribution width (RDW), reticulocyte count, and mean corpuscular volume of reticulocytes (MCVr). This study evaluated a total of 65 patients, consisting of nine patients with negative genetic analysis results and 56 patients with positive genetic analysis results. The Hb and RDW values in these two groups did not demonstrate statistical significance. On the other hand, there were statistically significant differences observed in the mean corpuscular volume (MCV), RBC count, reticulocyte count, and MCVr between the two groups. Furthermore, in the group of patients with positive genetic test results, specific genetic findings associated with different HPLC results were observed. In particular, 13 patients with positive genetic test results had normal HPLC findings. This study has demonstrated that HPLC, while serving as a valuable first-level test, has some limitations. Specifically, it has been observed that some patients may exhibit a negative HPLC result despite a positive genetic analysis. In addition to the presence of low levels of Hb and HPLC alterations, other parameters could potentially indicate the underlying mutations in the globin genes. Therefore, we propose that the complete blood cell count be utilized as a widely available parameter for conducting targeted genetic analyses to avoid the risk of overlooking rare hemoglobinopathies.

Iron/carbon conductive materials for enhancing anaerobic treatment of synthetic acrylamide wastewater

AbstractBACKGROUNDMost studies have focused on the degradation of acrylamide (AM) by a single strain. There are relatively few studies on the treatment of AM by anaerobic activated sludge. Previous studies have shown that conductive particles can change the mode of electron transport between anaerobic microorganisms. Therefore, this study compared the enhancement effect of three different particles (Fe3O4, granular activated carbon (GAC), graphite) on the treatment of synthetic AM wastewater by anaerobic activated sludge under different temperature conditions (30, 25, 20 °C) and particle dose (2, 6 g L−1).RESULTSThe results showed that 6 g L−1 GAC improved the removal rate of chemical oxygen demand (COD) and AM by 22.95% and 19% compared with the control group at 30 °C, respectively, indicating that the addition of GAC contributes to the degradation of AM and improves COD removal rate. Results of high‐performance liquid chromatography (HPLC) showed that the activated sludge with GAC obviously promoted the degradation of AM. Besides, a large amount of propionic acid was detected in all experimental groups during the reaction, and the activated sludge with GAC promoted degradation of propionic acid.CONCLUSIONAnaerobic activated sludge supplemented with sufficient GAC can not only absorb and degrade AM synchronously but also accelerate the conversion of intermediates, such as acrylic and propionic acids. Based on the results of HPLC and liquid chromatography–mass spectrometry, a possible method of degradation of AM by anaerobic activated sludge was proposed. © 2023 Society of Chemical Industry (SCI).

Combining orthogonal measurements to unveil diclofenac encapsulation into polymeric and lipid nanocarriers

The quantification of the drug associated to nanoparticle carriers, often expressed in terms of encapsulation efficiency, is a regulatory requirement. The establishment of independent methods to evaluate this parameter provides a means for measurement validation, which is critical in providing confidence in the methods and enabling the robust characterization of nanomedicines. Chromatography is traditionally used to measure drug encapsulation into nanoparticles. Here, we describe an additional independent strategy based on analytical centrifugation. The encapsulation of diclofenac into nanocarriers was quantified based on the mass difference between placebo (i.e. unloaded) and loaded nanoparticles. This difference was estimated using particle densities measured by differential centrifugal sedimentation (DCS) and size and concentration values measured by particle tracking analysis (PTA). The proposed strategy was applied to two types of formulations, namely poly(lactic-co-glycolic acid) (PLGA) nanoparticles and nanostructured lipid carriers, which were analysed by DCS operated in sedimentation and flotation modes, respectively. The results were compared to those from high performance liquid chromatography (HPLC) measurements. Additionally, X-ray photoelectron spectroscopy analysis was used to elucidate the surface chemical composition of the placebo and loaded nanoparticles. The proposed approach enables the monitoring of batch-to-batch consistency and the quantification of diclofenac association to PLGA nanoparticles from 0.7 ng to 5 ng of drug per 1 μg of PLGA, with good linear correlation between DCS and HPLC results (R2 = 0.975). Using the same approach, similar quantification in lipid nanocarriers was possible for a loading of diclofenac ≥1.1 ng per 1 μg of lipids, with results in agreement with the HPLC method (R2 = 0.971).Hence, the strategy proposed here expands the analytical tools available for evaluating nanoparticles encapsulation efficiency, being thus significant for increasing the robustness of drug-delivery nanocarriers characterization.

Extraction, structural characterization, and antioxidant activity of polysaccharides derived from Arctium lappa L.

Arctium lappa L. root has high nutritional and medicinal values and has been identified as a healthy food raw material by the Ministry of Health of the People's Republic of China. In the present study, an aqueous two-phase system (ATPS) of polyethylene glycol (PEG)-(NH4)2SO4 was used to extract Arctium lappa L. polysaccharides (ALPs) from the Arctium lappa L. roots, the optimal extraction conditions of crude ALPs were optimized by using the single-factor experiment and response surface methodology. The structure and composition of ALPs were determined by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and high-performance liquid chromatography (HPLC). At the same time, the antioxidant activity of ALPs was investigated by in vitro antioxidant experiment. The optimized extraction parameters for extraction ALPs were as follows: the PEG relative molecular weight of 6,000, a quality fraction of PEG 25%, a quality fraction of (NH4)2SO4 18%, and an extraction temperature of 80°C. Under these conditions, the extraction rate of ALPs could reach 28.83%. FTIR, SEM and HPLC results showed that ALPs were typical acidic heteropolysaccharides and had uneven particle size distribution, an irregular shape, and a rough surface. The ALPs were chiefly composed of glucose, rhamnose, arabinose, and galactose with a molar ratio of 70.19:10.95:11.16:6.90. In addition, the ALPs had intense antioxidant activity in vitro with IC50 values in the ·OH radical (1.732 mg/ml), DPPH radical (0.29 mg/ml), and superoxide anion (0.15 mg/ml) scavenging abilities. The results showed that ATPS was an efficient method to extract polysaccharides and could be used for the extraction of other polysaccharides. These results indicated that ALPs had great prospects as a functional food and could be exploited in multiple fields.

Synthesis and Characterization of Nanoparticles Extracted from <i>Catharanthus roseus</i> Plant

The Catharanthus roseus plant was extracted and converted to nanoparticles in this work. The Soxhlet method extracted alkaloid compounds from the plant Catharanthus roseus and converted them to the nanoscale. Chitosan polymer was used as a linking material and converted to Chitosan nanoparticles using Sodium TriPolyPhosphate (STPP). The extracted alkaloids were linked with Chitosan nanoparticles CSNPs by maleic anhydride to get the final product (CSNPs- Linker- alkaloids). The synthesized (CSNPs- Linker- alkaloids) was characterized using SEM spectroscopy UV–Vis., Zeta Potential, and HPLC High-Performance Liquid Chromatography. Scanning electron microscope (SEM) analysis shows that the Chitosan nanoparticles (CSNPs) have small dimensions with regular spherical and nanotube shapes of a diameter range of (49 - 70) nm. The final product (CSNPs- Linker- alkaloids) has two shapes (spherical particles and tubes) in nano dimensions and is close to each other compared to normal Chitosan. The absorption peaks for Chitosan (CS), Chitosan nanoparticles (CSNPs), Chitosan nanoparticles (CSNPs), and maleic anhydride revealed that converting Chitosan to Chitosan nanoparticles and mixing it with the plant extract, led to an increase in the absorption value and wavelength range. Also, the appearance of two peaks at 222 nm and 402 nm nano instead of the peak of Chitosan at 289.9 nm. Zeta Potential results of CSNPs- Linker- alkaloids showed that the extract of the nano-alkaloids bound to chitosan nanoparticles carries a positive charge of 54.4 mV. This surface charge is essential in maintaining the colloidal solution's stability in its natural form without changing. High-Performance Liquid Chromatography (HPLC) was used to estimate qualitative and quantitative plants extracted from Catharanthus roseus. Quantitative HPLC results show that Catharanthus roseus contains a good and acceptable concentration of Vinblastine, Vincristine, Vinorelbine, Vincamine, and Vintafolide (66.75, 242.91, 0.7, 83.77, 42.34) ppm respectively. The qualitative results show a good match for the influential groups of pure standard vincristine and alcoholic extract and dry powder of the Catharanthus roseus plant. The successful synthesis of nanoparticles from the Catharanthus roseus plant can be used in biosensors and biomedical applications.

Antifungal activity of potato glycoalkaloids and its potential to control severity of dry rot caused by Fusarium sulphureum

AbstractIdentifying novel sources of antifungal agents from common food waste (i.e., green potato peel) could provide an inexpensive alternative for botanical fungicides. Identification of the potato (Solanum tuberosum L.) glycoalkaloids (PGAs) content in the green peel by high performance liquid chromatography (HPLC), and the antifungal activity of PGAs against the potato dry rot pathogen Fusarium sulphureum were evaluated using addition of PGAs to the medium in vitro and injection of it into potato tubers in vivo. The results of HPLC showed that the average content of PGAs per kilogram green potato peel was 2238.76 mg, and the α‐chaconine content was about 1.8 times higher than that of α‐solanine. Antifungal activity test of PGAs in vitro uncovered that mycelium growth rate of F. sulphureum was inhibited in potato dextrose agar (PDA) medium with varying concentrations of PGAs, and the inhibition rate was positively correlated with PGAs concentration. Moreover, PGAs were also capable of reducing the contents of malondialdehyde, total phenols, flavonoids as well as the activities of peroxidase and superoxide dismutase induced by F. sulphureum through inhibiting or killing part of mycelium. These findings suggest that the protective effect of PGAs against potato dry rot might be associated with the direct fungistatic effect on the pathogen. Thus, PGAs can serve as a promising botanical fungicide to substitute, at least partially, the use of synthetic fungicides in the disease management of potato.

Rapid screening of 14 antibacterial drugs in anti-acne cosmetics using ion mobility spectrometry coupled with solid-phase extraction

The main methods currently used to detect illegally added chemicals in cosmetics include thin-layer chromatography, high performance liquid chromatography (HPLC), gas chromatography (GC), and liquid chromatography-mass spectrometry (LC-MS). Compared with other analytical techniques, these methods have the advantages of high sensitivity, specificity, and accuracy, all of which are required in practical detection work. However, they also present a number of limitations, such as long analysis times and requirements for skilled operators and strictly controlled laboratory environments. Supervision, a growing trend in market surveillance, requires rapid and effective methods to screen illegally added chemicals. The suspected samples are sealed for some time and then sent to the laboratory for further testing. Ion mobility spectrometry (IMS) is a new type of trace gas separation technology that was developed in recent years. The principle behind IMS is the separation and characterization of chemical species based on differences in the migration speed of their gas-phase ions under an electric field. As this technology has the advantages of miniaturization, easy operation, and quick responses, it is widely used in food and drug quality testing, as well as other related fields. However, it is rarely used in cosmetic detection, likely because the cosmetics matrix is highly complex, which can interfere with ion determination. Thus, optimizing the pretreatment process of cosmetics for IMS is important. In this work, solid-phase extraction (SPE) is combined with IMS to establish a method for the rapid screening of 14 antibacterial drugs in anti-acne cosmetics. The IMS detection parameters, sample extraction conditions, and SPE clean-up conditions (SPE column, type of leachate, type and volume of eluent) were studied and optimized in detail. The sample was extracted with 80%(v/v) acetonitrile aqueous solution (containing 0.2% (mass fraction) trichloroacetic acid), loaded onto an activated Oasis® MCX SPE column, leached with 3.0 mL of methanol, and eluted with 1.0 mL of 2% ammonia methanol solution. The eluate was then directly injected into the IMS instrument. The IMS parameters were as follows: positive ion source voltage=2200 V, transfer tube voltage=8000 V, inlet temperature=180 ℃, transfer tube temperature=180 ℃, ion gate voltage=50 V, gate voltage pulse width=85 μs, and migration gas flow rate=1.2 L/min. The migration times for the 14 antibacterial drugs ranged from 11 to 17 ms, and the detection limits for the target compounds ranged from 0.2 to 1.2 μg/g. Owing to the narrow linear range of IMS, a quantitative method employing HPLC was also established to optimize the SPE pretreatment step and verify the positive samples. Chromatographic separation was conducted on a Phenomenex Luna C18 column (250 mm×4.6 mm, 5 μm), with a column flow rate of 1.0 mL/min and gradient elution with mobile phases A (0.01 mol/L potassium dihydrogen phosphate adjusted to pH 4.0 with phosphoric acid) and B (acetonitrile). The column temperature was set to 35 ℃, and the injection volume was fixed at 5 μL. A total of 25 cosmetics samples were screened, and one positive sample was found to be consistent with the results of HPLC. The proposed method is fast, simple, and efficient, and it can be used for the rapid screening of the 14 antibacterial drugs in anti-acne cosmetics. Pretreatment can significantly reduce the influence of the cosmetic matrices on the determination results, improve instrument sensitivity, and effectively decrease the occurrence rate of false positives and negatives. The technique developed in this work can improve the efficiency of screening for illegally added chemicals and expand the applications of IMS for detecting various chemicals in complex matrices, such as cosmetics.