Diode Array Detection Research Articles

Determination of 31 Antimicrobials in Human Serum Using Ultra-High Performance Liquid Chromatography With Diode Array Detection for Application in Therapeutic Drug Monitoring.

A versatile ultra-high performance liquid chromatography method with diode array detection was developed to quantify a wide range of antibiotics in human serum. This method addresses the need for rapid and accurate determination of antibiotic levels to ensure effective patient treatment and support the fight against antibiotic resistance. This method assesses 31 different compounds covering β-lactams, fluoroquinolones, antifungals, antituberculars, and more. Proteins were precipitated using methanol or acetonitrile, and drugs were extracted by liquid-liquid extraction with dichloromethane. Separation of the antimicrobials was achieved on a pentafluorophenyl column, using a mobile phase of phosphoric acid (0.01 mol/L) and acetonitrile in a gradient elution mode, with a flow rate of 500 μL/min. Almost all compounds were detected at 200 nm. The total analysis time for this method was kept under 18 minutes, including equilibration time. This efficient method enables fast determination of numerous antimicrobial classes, providing clinicians with an essential tool for ensuring effective patient treatment and combating antimicrobial resistance.

Vasculo-Protective Effects of Standardized Black Chokeberry Extracts in Mice Aorta

Black chokeberry (Aronia melanocarpa <Michx.> Elliot) represents a rich source of dietary polyphenols and other bioactive phytochemicals with pleiotropic beneficial cardiovascular effects. The present study was aimed at evaluating the ex vivo effects of two black chokeberry extracts (BChEs), obtained from either dry (DryAr) or frozen (FrozAr) berries, on oxidative stress and vascular function in mice aortic rings after incubation with angiotensin 2 (Ang 2), lipopolysaccharide (LPS) and glucose (GLUC) in order to mimic renin–angiotensin system activation, inflammation and hyperglycemia. The identification of phenolic compounds was performed by means of liquid chromatography with a diode array detector coupled with mass spectrometry using the electrospray ionization interface. The BChE obtained from the FrozAr was rich in cyanidin glucoside, rutin and caffeic acid, while the one obtained from the dried berries was rich in rutin, caffeic acid and chlorogenic acid. Mice aortas were dissected and acutely incubated (12 h) with Ang2 (100 nM), LPS (1 µg/mL) or GLUC (400 mg/dL) in the presence vs. absence of the two BChEs (1, 10, 50, 75, 100, 500 µg/mL). Subsequently, the tissues were used for the assessment of (i) hydrogen peroxide (H2O2) and superoxide production (using two methods, spectrophotometry and immunofluorescence), (ii) H2O2 scavenger effect and (iii) vascular reactivity (using the organ bath/myograph system). After exposure to Ang2, LPS or GLUC, both types of extracts decreased the H2O2 and superoxide levels in a concentration-dependent manner starting from either 50 µg/mL or 100 µg/mL. Also, in the highest concentrations (100 µg/mL, 150 µg/mL and 500 µg/mL), both extracts elicited a significant scavenger effect on H2O2 (similar to catalase, the classic H2O2 scavenger). Moreover, at 100 µg/mL, both extracts were able to significantly improve vascular relaxation in all stimulated aortic rings. In conclusion, in mice aortas, black chokeberry extracts in acute application elicited a concentration-dependent vasculo-protective effect through the reduction of oxidative stress and the alleviation of endothelial dysfunction in ex vivo conditions that mimic cardio-metabolic diseases.

Using phenolic compounds from the Mediterranean Sea west of Egypt to categorize the sediment quality

Background and aimDespite having a low population, Egypt’s west coast is heavily industrialized resulting in large amounts of industrial wastewater that are dumped directly into the sea, severely polluting the area with various toxins. Numerous human activities release phenolic chemicals into the environment, which can be found in water and sediment. These materials are used to make compounds such as dyes, pesticides, explosives, and pharmaceuticals in a variety of industrial processes. Insufficient research has been done on the infiltration of phenolic compounds, which are organic serious pollutants, into the aquatic environment along the Mediterranean coast of Egypt, particularly the western shore. The research investigates the ecological dangers and concentration of eleven phenolic compounds found in bottom sediments on Egypt’s coastal area west of Alexandria.MethodsBefore analysis, stainless steel sieves were used in a mechanical sieving system to homogenize and size-fractionate samples of superficial sediment that were gathered from each of the 15 measurement locations along Egypt’s west coast. Total nitrogen and total organic carbon were also determined. Samples of dried bottom sediment were extracted with a solution of NaOH and methanol in order to determine the phenolic compounds, the final concentrated extract volume of each sample was reduced to 1.0 ml under a mild stream of purified nitrogen gas. A high performance liquid chromatograph (HPLC) (Series 1100, Agilent Technology Inc., Santa Clara, CA, USA) fitted with an autosampler, vacuum degasser, quaternary pump, and diode array detector was used to analyze eleven phenolic compounds.ResultsThe mean concentration of total eleven phenolic ranged between 1.02–5.62 µg g−1 with the mean value of 3.17 µg g−1 (SD, ±1.68), respectively. It was discovered that the concentration of additional phenolic compounds was not uniform, with their share of less than 10% in the total phenolic compounds.ConclusionPhenol was the most prevalent compound, with pentachlorophenol (PCP) coming in second with a normal centralization of 18.454 and 10.785 µg g−1, respectively. It was found that the remaining phenolic compounds had heterogeneous convergences, with less than 10% of them contributing to the total amount of phenolic compounds. Due to several activities, including force stations that utilize tar instead of gas, the oil pipe organization, and several tourist towns, the SidiKirir and Dabaa zones had the highest quantities of phenol and pentachlorophenol.

Comparative Analysis of Ground-Based and Satellite-Derived UV Index Levels in Natal, Brazil

The ultraviolet radiation index (UV index–UVI) is a dimensionless indicator that informs the intensity of ultraviolet radiation on the Earth’s surface. It makes it easier for people to assess UV levels and understand how to protect themselves from excessive Sun exposure. In Brazil, however, the information regarding UV is scarce, with low spatial and temporal coverage. Thus, continuous monitoring is conducted through satellites, although ground-based monitoring of UV is more accurate than satellite retrievals, and comparisons are necessary for validation. This paper aims to compare the levels of UV index measured on the ground and by satellite (OMI and GOME-2) over Natal, Brazil (05.78°S; 35.21°W) from 2005 to 2022. The comparison was made under clear-sky conditions using METAR cloud cover and LER data. Characterization of the diurnal and seasonal variability of the ground-based UV index levels under all and clear-sky conditions is also reported. The analysis indicates that all-sky UVI is, on average, higher than the clear-sky UVI due to the frequent broken cloud conditions that, on average, result in the enhancement of the noon UVI. The two satellite sources (OMI noontime and overpass) and GOME-2 noontime are reliable sources for UV index, which show good agreement with ground-based measurements, with UVI estimated from OMI both at the overpass and noontime being less biased than GOME-2-estimated UVI. Such a process of data verification is important should these data be used for long-term trend analysis or the monitoring of UV exposure risk and possible impacts on human health.

Facile and rapid preparation of fluorinated imprinted adsorbent for magnetic solid phase extraction of liquid-crystal monomers.

Anew fluorinated imprinted adsorbent (MIA) for magnetic solid phase extraction (MSPE) ofliquid crystal monomer (LCM) pollutantswas one-pot prepared within 3.5h using 4-[difluoro(3,4,5-trifluorophenoxy)methyl]-3,5-difluoro-4'-ethyl-biphenyl (DFBP) as template and 1H,1H,2H,2H-heptadecafluorodecyl acrylate/vinylanthracene as dual monomers. The structure, morphology, and magnetic properties of MIA fabricated were investigated by various characterization techniques. Under the optimal conditions the prepared MIA presented satisfactory specific recognition performance. The recognition factor and adsorption capacity towards DFBP were 2.7 and 15.9mg/g, respectively. The specific recognition behaviors of MIA/MSPE towards DFBP were surveyed by means of adsorption kinetics and adsorption isotherms. Combining MSPEwith HPLC coupled to a diode array detector (DAD), asensitive, reliable and anti-interference method for the monitoring of LCMs residuals in various environmental water and soil samples was established. The achieved enrichment factors were 132-248 and 96-204 in water and soil samples, respectively. The corresponding limits of detection were 0.0017-0.0051μg/L and 0.087-0.28μg/kg, respectively. Moreover, confirmatory experiments were adopted to inspect the accuracy of theestablished MIA/MSPE-HPLC/DAD approach. To the best of our knowledge, this is the first time that an imprinted material has been used forspecific isolation and capture of LCMs which have been classified as emerging organic pollutants.

Application of deep eutectic solvent based dispersive liquid–liquid microextraction method followed by HPLC-DAD for quantification of selected neonicotinoid pesticides in vegetable oils

The use of deep eutectic solvents (DES) as alternative green solvents in various analytical chemistry fields has garnered attention of researchers globally. Therefore, this study presents environmentally friendly DES for extraction of selected neonicotinoids (acetamiprid, imidacloprid, thiacloprid and thiamethoxam) prior to their determination using high-performance liquid chromatography- diode array detector (HPLC-DAD). The DES mixture that resulted in the highest extraction recoveries of neonicotinoids (NEOs) was choline chloride with ethylene glycol (CCl:EG) and nuclear magnetic resonance and Fourier transform infrared confirmed the successful synthesized CCl:EG. Thereafter, the CCl:EG was applied in dispersive liquid–liquid microextraction (DLLME) for the preconcentration and extraction of acetamiprid, imidacloprid, thiacloprid and thiamethoxam. The optimum factors affecting extraction efficiency of the DES-DLLME procedure were 0.8 mL (DES volume), 4.5 min (extraction time), 0.5 mL (eluent volume), 7 pH and 75 s (eluent time). The optimized DES-DLLME achieved limit of detection (LOD) and quantification (LOD) range of 0.4–4.95 ng.µL−1 and 1.43–9.70 ng.µL−1 respectively. Additionally, the extraction method achieved good accuracy (79.0–119.6 %), preconcentration factors (39.3–118), interday (0.61–1.62 %) and intraday (0.1–0.98 %) precisions. The greenness assessment of the proposed DES-DLLME method using AGREE, NEMI and AES tools revealed that the method was green. Finally, the developed DES-DLLME method was applied to real vegetable oils and the concentrations were below detection limits.

Synthesis of a bimetal-organic framework-cobalt oxide nanoflowers (Ni/Co-MOF@Co3O4 NFs) for sensitive tebuconazole extraction from fruit juice and water samples using micro-solid phase extraction-HPLC-DAD

Tebuconazole (TBZ) is a widely used triazole fungicide that poses potential risks to human health and the environment due to its persistence in food and water. Effective monitoring of TBZ residues is crucial for ensuring food safety and environmental protection. This study presents a novel method for synthesizing Ni/Co-MOF@Co3O4 nanoflowers (NFs) and their application in extracting TBZ from water and fruit juice samples via micro-solid phase extraction (µ-SPE). Ni/Co-MOF@Co3O4 NFs was synthesized using the hydrothermal technique followed by calcination. The synthesized nanoflowers were characterized through SEM, XRD, and FT-IR analyses. Optimal extraction conditions were established at pH 8, using 10 mg of adsorbent, with adsorption and desorption times of 3 and 2 min, respectively. TBZ analysis was conducted using HPLC with a Poroshell 120 EC-C18 column and a diode array detector (DAD). The method demonstrates excellent recovery rates (90–102 %) and RSD% of 3.7 % in spiked fruit juice and natural water samples. The analytical performance showed a wide linear range (1–2000 µg L−1) with a high correlation coefficient (R2 = 0.9998), a detection limit of 4.0 ng L−1, and a quantification limit of 13.0 ng L−1. This approach is fast, simple, and highly sensitive, offering a reliable technique for detecting trace levels of TBZ in food and water environments.

Two-pot synthesis of polypyrrole‐coated rubber foam for the extraction of carbendazim residue in orange juice

Natural rubber foam was coated with polypyrrole (PPy) via a rapid two-pot synthesis. This PPy-coated rubber foam was used as sorbent for the solid-phase extraction of carbendazim in fresh orange juice. The extracted carbendazim was quantified by high performance liquid chromatography with diode array detection (HPLC-DAD). Under the optimal conditions, the method exhibited linearity in the range of 25–1000 µg kg−1 with a limit of detection (LOD) of 24.1 µg kg−1 and a limit of quantification (LOQ) of 80.5 µg kg−1. Good reproducibility (RSD < 2.5 %, n = 6) and good reusability (RSD < 3.8 %, n = 10) were achieved. The sorbent was applied to extract carbendazim in fresh orange juice. Accuracy was excellent and recoveries were attained from 81.6 % to 104.8 %. The found carbendazim in real samples ranged from 40.0 µg kg−1 to 101.1 µg kg−1. The developed sorbent can be produced in large quantities at a reasonable cost and utilized as an environmentally friendly sorbent for the extraction of pesticides and other trace organic substances.

Capillary Electrophoresis with Diode Array Detection for the Quantification of Triptorelin and Lanreotide in Pharmaceutical Quality Control: Development, Validation, Greenness and Practicality Evaluation

Abstract Aim Capillary electrophoresis (CE)-based methods hold significant potential for routine use in pharmaceutical quality control (QC) laboratories. Therefore, this study aimed to develop a novel, green, and simple hydrodynamically open-system capillary zone electrophoresis method with diode-array detection (CZE-DAD) for the simultaneous analysis of lanreotide and triptorelin in a single electrophoretic run and to objectively evaluate the analytical technique’s greenness and practicality for application in the pharmaceutical QC settings. Materials and Methods The two therapeutic peptides were analysed using a commercially available CZE-DAD analytical system. The separation process was optimised by changing the composition and concentration of the background electrolyte (BGE). The developed method was validated in accordance with the International Conference on Harmonisation (ICH) Q2(R1) guidelines, and Diphereline® (powdered form for injection, 0.1 mg of triptorelin acetate) was used as a real dosage form of triptorelin. Greenness and practicality were evaluated using Green Analytical Procedure Index (GAPI), Analytical GREEnness (AGREE), and Blue Applicability Grade Index (BAGI) metrics. Results The optimised method utilised 250 mmol/L formic acid as the BGE, achieving high separation efficiency and short migration times, where both the peptides were analysed in &lt;5 min. The method showed excellent linearity (r 2 &gt; 0.99), precision (relative standard deviation [RSD] &lt;7.1%), and accuracy (92.7%–113.6%). The limit of detection (LOD) and limit of quantification (LOQ) were determined to be 0.5 μg/mL and 2 μg/mL, respectively. The method was also found to be environmentally friendly, with high scores achieved in both the GAPI and AGREE assessments, while also being practical, with a BAGI score of &gt;60. Conclusions The newly developed CZE-DAD method proved to be a reliable, efficient, and environmentally sustainable alternative to liquid chromatography (LC)-based methods for the analysis of lanreotide and triptorelin. The method’s acceptable validation parameters and favourable greenness and practicality scores support its high application potential in pharmaceutical QC laboratories.

New Antioxidant Caffeate Esters of Fatty Alcohols Identified in Robinia pseudoacacia

The stem bark of black locust (Robinia pseudoacacia L.) was extracted, and nine antioxidant compounds (R1–R9) were detected by high-performance thin-layer chromatography combined with the radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH•) assay, multi-detection, and heated electrospray high-resolution mass spectrometry. For structure elucidation, the methanolic crude extract was fractionated by solid-phase extraction, and the compounds were isolated by reversed-phase high-performance liquid chromatography with diode array detection. The structures of isolated compounds were elucidated by nuclear magnetic resonance and attenuated total reflectance Fourier-transform infrared spectroscopy as well as gas chromatography-mass spectrometry to determine the double bond position. 3-O-Caffeoyl oleanolic acid (R1), oleyl (R2), octadecyl (R3), gadoleyl (R4), eicosanyl (R5), (Z)-9-docosenyl (R6), docosyl (R7), tetracosyl (R8), and hexacosanyl (R9) caffeates were identified. While R1 has been reported in R. pseudoacacia stem bark, the known R3, R5, R7, R8, and R9 are described for the first time in this species, and the R2, R4, and R6 are new natural compounds. All nine caffeates demonstrated antioxidant activity. The antioxidant effects of the isolated compounds R1–R8 were quantified by a microplate DPPH• assay, with values ranging from 0.29 to 1.20 mol of caffeic acid equivalents per mole of isolate.

Enhancing Doxorubicin Detection: Multiphase Electroextraction for Efficient and Affordable UHPLC-DAD Analysis in Saliva.

Attesting optimal drug concentrations in biological fluids is crucial to ensure precise dosage adjustment, to guarantee therapy adherence, and to manage side effects in chemotherapy. Accurate drug determination relies on liquid chromatography and advanced detectors, with sample preparation playing a pivotal role, especially in complex matrices such as biological fluids. This study introduces a multiphase electroextraction (MPEE) of doxorubicin (DOX) in saliva by utilizing a paper point, followed by ultra-high-performance liquid chromatography coupled to diode array detection. The extraction time and electric potential were carried out by using the Doehlert optimization approach, whereas the desorption solvent was fine-tuned through the centroid-simplex experimental design. After optimization, DOX and the internal standard were extracted in 35min, utilizing an applied voltage of 300V and a multiwell plate capable of simultaneous extraction of 66 samples. The recovery was 87%-101%, with a linear range between 50 and 500µgL-1 (R2>0.999). The intra- and inter-assay coefficients of variation for precision were <10%, and the limit of detection and limit of quantification were 25 and 50µgL-¹, respectively. When applied to five different fortified saliva samples, there were no statistically significant differences in the detected concentrations. Although the enrichment factor (0.6) was not as high as expected, the other results confirm that the method obtained is suitable for monitoring DOX in this complex matrix and can contribute to further developments in sample preparation using MPEE approaches.

Optimization of the Microwave-Assisted Extraction Conditions for Phenolic Compounds from Date Seeds.

Date seeds, often discarded during industrial processing, are an underexploited by-product rich in polyphenols with significant antioxidant potential. This study explores the extraction of polyphenols from date seeds using microwave-assisted extraction (MAE) with an organic solvent. The extraction process was optimized using response surface methodology (RSM), focusing on extraction time, ethanol concentration, and temperature. The optimal extraction conditions were 46% (v/v) of ethanol, at 62 °C and for 27.3 min. Under these optimized conditions, the extraction yield and total phenolic content of the extract are 12.5% and 59 mg gallic acid equivalent g-1 of date seed, respectively, as confirmed by the experimental tests. The extract's antioxidant activity was confirmed through DPPH, ABTS, and FRAP assays. High-performance liquid chromatography with diode-array detection (HPLC-DAD) identified major phenolic compounds, including procyanidin B1, catechin, quercetin-3,5'-di-O-glucoside, epicatechin, procyanidin B, and syringic acid, alongside eight other tentatively identified compounds. These findings underscore the potential of MAE as an environmentally friendly technique for producing polyphenol-rich extracts from date seeds, adding value to this by-product and opening avenues for its application in food and nutritional products.

MCM-41 based dispersive micro-solid phase extraction of selected cephalosporin antibiotic residues from water samples prior to liquid chromatographic quantification

The occurrence of antibiotics in water bodies is of concern owing to the serious risk they pose to the environment, water security, aquatic organisms, and human health. In this study, mesoporous silica (MCM-41) nanostructured material was synthesised and characterized by various analytical techniques to determine its morphology and dimension, functional groups, surface charge, and textural properties. The nanostructured MCM-41 was used as an adsorbent in ultrasound-assisted dispersive micro solid-phase extraction (UA-D-µ-SPE) of cefadroxil (CFDX) and cephalexin (CPLX) in water samples. The concentration of the analytes in aqueous solution and real water samples was determined using high-performance liquid chromatography coupled with diode array detection (HPLC-DAD). The developed method for CFDX and CPLX in various water samples exhibited relative linear ranges of 0.1–600 µg/L and 0.1–550 µg/L, respectively, and correlation coefficients ranging from 0.9923–0.9993. Under optimum condition, the UA-D-µ-SPE/HPLC-DAD method displayed low limits of detection (LOD) and quantification (LOQ), with values ranging from 0.02–0.16 µg/L and 0.067–0.53 µg/L, respectively. The investigated intraday and interday accuracy in spiked water samples showed acceptable extraction efficiencies with a range of 73.5–98.1% and a relative standard deviation less than 6.0%. Moreover, the performance of MCM-41 was also assessed for the removal of cephalosporin antibiotics aqueous solutions. The kinetic and isotherm studies revealed that the adsorption process followed pseudo-second order and the Langmuir model, respectively. Furthermore, the maximum adsorption capacities for CFDX and CPLX were 43.2 and 47.8 mg/g. Lastly, the UA-D-µ-SPE/HPLC-DAD method was successfully applied in extracting, preconcentrating, separating and determining CFDX and CPLX in wastewater and surface water samples. These results demonstrated that MCM-41 can be applied in the removal of cephalosporin antibiotics from aquatic environments.

Robust In Vitro HPLC-DAD Method for Accurate Quantification of N-Carbamylglutamate in Drug Formulations

A comprehensive in vitro testing method has been developed and validated for accurately quantifying N-Carbamylglutamate (Carglumic acid) using a high-performance liquid chromatography instrument with a diode array detector. A method specifically developed for pharmaceutical quality control utilizes a reverse-phase C18 column for precise and reliable measurement of Carglumic acid. The chromatographic parameters were refined for peak resolution, employing a phosphate buffer and acetonitrile as the mobile phase, with detection setup at 205 nm. The method was validated under ICH Q2(R2) requirements. The approach exhibited a significant level of specificity, with no interference from excipients or other possible impurities. Linearity was achieved across the entire concentration range, yielding an R² value of 0.999. Precision (RSD ≤ 2) was demonstrated by intra- and inter-day variability being within acceptable limits. Recovery tests validated accuracy (98 – 102%). Determining the limit of detection (LOD, 0.1 ppm) and the limit of quantitation (LOQ, 0.5 ppm) was conducted. This in vitro test method was valid and effective for the routine quantification of Carglumic acidin pharmaceutical formulations, serving as a crucial tool for ensuring product quality and regulatory compliance. The methods' elevated sensitivity and endurance make it appropriate for bioanalytical applications, such as dissolution testing and stability analysis.

Histological Study and Chemical Composition of Apium graveolens: In Vivo Antimicrobial Activity

The purpose of the current investigation is to evaluate the methanolic extract from Apium graveolens seeds for chemical composition and in vivo antimicrobial activity, supported by a histological study. The chemical profile of the methanolic extract was identified using high-performance liquid chromatography diode array detector analysis. The toxicity and antimicrobial effects of the methanolic extract were examined through in vivo experiments on rats weighing 220 ± 5 g. The histological study was conducted using the rats’ ileum. The methanolic extract (80%) contained sinapic acid (49.9%), ascorbic acid (25.4%), butylated hydroxyanisole acid (6.1%), and quercetin (8.2%), with a yield ratio of 11.74%. The dose of 50 mg/kg of the methanolic extract did not lead to animal lethality or toxicity symptoms. Two days after treatment, the blood cultures of all females treated with the methanolic extract at 50 mg/kg showed sterility (100%). The same result appeared on the fifth day after treatment in all males of the same group. Histopathological examination revealed normal and well-preserved architecture of the ileum in both sexes. The study concludes that the methanolic extract of Apium graveolens possesses significant antimicrobial capacity. KEYWORDS Anatomopathology, celery, chemical compounds, enteric infection, HPLC, rats

Matrix Effect on a New Dispersive Liquid–Liquid Microextraction‐High‐Performance Liquid Chromatography–Diode Array Detection Method for the Determination of Efavirenz in Human Plasma

ABSTRACTA high‐performance liquid chromatography–diode array detection (HPLC‐DAD) method was developed and validated for the determination of efavirenz in human blood plasma samples from patients taking the antiretroviral drug. Results were compared with those previously obtained using gas chromatography/mass spectrometry (GC/MS) on the same sample extracts using dispersive liquid‐liquid microextraction. Validation of the HPLC‐DAD method yielded the United States Food and Drug Administration guidelines acceptable values. However, when validated, the accuracy using the HPLC‐DAD method was poor in contrast to GC/MS at the lower limit of quantification (LLOQ) level. The linearity of the HPLC‐DAD method was good with a coefficient of determination (R2) of 0.9922. The linear range of the calibration curve was 0.05–0.5 µg/mL. The LLOQ was 0.03 µg/mL at which spike level the accuracy was 8.9% (n = 3) and the precision was 8.3% (n = 3). Statistical analysis of the data showed that there were no systematic errors introduced in the HPLC‐DAD method but that there was a matrix effect that suppressed the signals and led to random error and subsequently impacted the accuracy of the results.

Chromatographic assay of recently approved co-formulation of Vonoprazan fumarate with low dose Aspirin: AGREE, Complex MoGAPI, and RGB 12-model assessments

Two simple, valid and green chromatographic based techniques are developed in the present work for first time to simultaneously analyze the recently approved combination of Aspirin (ASP) with the novel gastro-protective agent Vonoprazan (VON). First method is an HPLC-DAD “diode array detection”, where separation was successful using C18 (250 × 4.6 mm) column with isocratic elution of phosphate buffer-pH 6.8 and acetonitrile in ratio of 63:37 with detection at 230 nm. Second method is an HPTLC method on HPTLC silica plates using ethyl acetate: ethanol (75%): ammonia (5:5:0.05 v/v) mobile phase followed by densitometric scanning at 230 nm. The methods were applied successfully for analysis of VON and ASP mixture in laboratory-prepared tablets and the methods were validated in regards to linearity, precision, accuracy and selectivity. The proposed methods are assessed for their greenness and whiteness as well using the “Analytical GREEnness Metric Approach”, “Complementary Modified Green Analytical Procedure Index” and the new algorithm “RGB 12 model” (Red-Green-Blue) and proved the greenness and the sustainability of the methods in the routine assay of the newly marketed formulation.

Comprehensive honey analysis: A novel HPLC-DAD method for hydroxymethylfurfural quantification and quality evaluation via diastase activity and sugar profile determination

Ensuring the authenticity and quality of honey is essential to safeguarding consumer health and combating food fraud. The primary analyses for honey quality involve determining diastase activity (DA), 5-hydroxymethylfurfural (HMF), and carbohydrate composition. A new high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) method was developed, for the precise quantification of HMF, a key marker of honey quality and degradation. Utilizing a Phenomenex Kinetex RP-18 column (5 µm, 150 × 4.6 mm i.d.), with a mobile phase containing water and methanol (95:5, v/v) in gradient mode, at a flow rate of 1 mL/min, and UV detection at 284 nm, the method achieved rapid and efficient separation within 10 minutes, with a low detection limit of 0.03 mg L−1, and demonstrated good linearity, precision and recovery rates. The carbohydrate composition of honey, specifically glucose, fructose, saccharose, and maltose, was analysed using a HPLC with refractive index detection (HPLC-RI) method, using a Phenomenex Luna Omega Sugar column (3 µm, 250 ×4.6 mm i.d.), with a mobile phase composed of acetonitrile and water (85:15, v/v). This analytical protocol, incorporating the quantification of maltose, a critical yet often overlooked sugar, significantly bolsters the standard evaluation framework for honey authenticity. DA, a crucial enzymatic indicator, was assessed via the Schade method, providing additional insights into the enzymatic integrity and freshness of the honey samples. The methods were applied to analyse 65 commercial Spanish honey samples, revealing significant compliance with EU regulatory standards, yet also uncovering situations of potential adulteration. This research adds to the ongoing discussions on food safety by offering improved and dependable techniques for thoroughly assessing honey samples.

Trade-Off Between Growth Regimes in Chlorella vulgaris: Impact on Carotenoid Production

With the increasing awareness of socio-environmental issues, a global trend has emerged emphasizing the valorization of natural ingredients that promote health and well-being within sustainable production systems, such as microalgae-based carotenoids. Currently, little is understood about the correlation between biomass productivity and carotenoid content, which is a fundamental parameter for facilitating the immediate expansion of microalgae bioprocesses and ensuring the availability and industrial viability of these compounds. In this context, this study aims to investigate the carotenoid profile of Chlorella vulgaris through growth curve experiments conducted under photoautotrophic and heterotrophic regimes. Additionally, a trade-off analysis was performed for the production of carotenoids from microalgae. Carotenoids were quantified using high-performance liquid chromatography coupled with diode array and mass spectrometry detectors (HPLC-PDA-MS/MS). The performance of kinetic phases and energy demands across growth regimes was assessed to provide insights into production trade-offs. The results indicated that a total of 22 different carotenoids were identified in all the extracts. The all-trans-lutein and all-trans-β-carotene were the majority compounds. The total carotenoid content of Chlorella vulgaris revealed significant differences in the kinetic phases of carotenoid production, indicating that carotenoid volumetric production is only viable if the cultures are conducted until the log and stationary phases, based on the function of the biomass volumetric production (weight.volume−1). Therefore, the best trade-off for the process was to provide photoautotrophic growth until the exponential phase (log). Under this condition, the maximum carotenoid and lutein content was 2921.70 µg.L−1, reaching a maximum cell biomass of 1.46 g.L−1. From an environmental/economic point of view, the energy demand was 7.74 kWh.L−1. Finally, the scientific advances achieved in this study provide a holistic view of the influence of the main cultivation methods on the production of microalgae carotenoids, suggesting a viable initial direction for different industrial applications.

Comparative phytochemical profile and biological activity of three Terminalia species as alternative antimicrobial therapies

Ethnopharmacological relevanceMedicinal plants can help combat antibiotic resistance by providing novel, active molecules. Three plant species of the Terminalia genus are widely used in traditional medicine in the Mouhoun region for the treatment of cutaneous and respiratory diseases. Therefore, it is important to determine the ethnopharmacological potential of bark extracts from the trunks of these three Terminalia species. Aim of the studyThis study compared the phytochemical and biological activities of extracts from three Terminalia species to determine their ethnopharmacology. Materials and methodsThe medicinal properties of the extracts were assessed based on their ability to inhibit the growth of the following microorganisms: Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans, Candida krusei, Candida glabrata, and Candida tropicalis. The significant interest in these medicinal plants among the local communities were elucidated by their antioxidant properties and phytochemical composition, along with the detection key bioactive compounds. Major phytochemical groups and phenolic compounds were determined using high-performance liquid chromatography with a diode array detector. These phytochemical findings were validated by evaluating the antioxidant capacity of the extracts using DPPH, FRAP, and ABTS assays. ResultsHydroethanolic, ethanolic, and hexane extracts from the bark of three Terminalia species inhibited the growth of both bacteria and fungi, as evidenced by their minimum inhibitory concentrations (MICs).The findings showed that Terminalia species were most effective against various tested bacteria and fungi, with MICs ranging from 0.1 to 6.25 mg/mL. Terminalia avicennioides, Terminalia macroptera, and Terminalia laxiflora extracts demonstrated 50 % inhibition of DPPH at concentrations ranging from 0.04 to 0.6 mg/mL. Phytochemical analysis revealed the presence of several families of chemical compounds, such as total phenolics and flavonoids. Phenolic compounds identified by HPLC in ethanolic extracts of T. avicennioides, such as isorhamnetin, quercetin, and ferulic acid, are recognised for their antimicrobial and antioxidant properties. ConclusionThese findings establish an ethnobotany for these three Terminalia species, with their chromatographic characteristics facilitating the identification of key molecules of interest. The ethanolic extract of T. avicennioides can be used in phytomedicinal formulations against bacterial (P. aeruginosa and S. aureus) and fungal (C. albicans and C. glabrata) infections, both of which are recurrently recorded in certain skin and respiratory tract diseases.