Current Analytical Chemistry - Online First

Despite the widespread use of Ephedra altissima plant in traditional Algerian medicine, the biological potential of this species has still not been well explored.

This study, for the first time, focused on determining the effect of extraction methods and solvents on the phenolic content and antioxidant ability of the aerial part of Ephedra altissima.

Extraction was carried out by maceration and Soxhlet using the solvents H2O, Methanol/H2O and Petroleum ether. The chemical profile of E. altissima was determined by a qualitative HPLC/UV–Visible, and the antioxidant potential was evaluated by in vitro and in-silico studies.

The aqueous extract obtained by maceration exhibited the greatest total phenol content, while the petroleum ether prepared by Soxhlet extraction demonstrated the highest total flavonoid and condensed tannin contents. The HPLC profile showed the presence of a variety of phenolic compounds. The in-vitro assay results indicated good antioxidant potential. Gallic acid and sinapic acid were highlighted as the most potent antioxidants in the Soxhlet hydro-methanolic and petroleum ether extracts, respectively, according to the machine learning model. Molecular docking predicted the possible antioxidant potential of E. altissima phytocompounds by the interaction with human peroxiredoxin 5, and epicatechin was the most effective ligand. Molecular dynamics simulations confirmed the stability of the epicatechin-Prdx5 complex. Multivariate analysis was used to categorize the Ephedra altissima extracts into three groups according to their phenolic compound content and in vitro antioxidant ability.

Overall, the results of the present study revealed that the choice of solvent and extraction technique directly influence the biomolecule content and bioactivity of Ephedra altissima aerial part extracts.

Milk, an essential part of diet is comprised of all indispensable nutrients. However, it proves to be beneficial only if it is available in its pure form.

The current study aimed to evaluate packaged milk samples collected from local markets of Karachi and to assess level of consumer awareness about health risks associated with substandard milk consumption.

Package milk samples were assessed collectively for physical parameters, and microbial load. Seventeen colour-based chemical tests were also conducted to detect different dyes, preservatives, and other added chemicals as adulterants in milk. A household-based community survey was conducted to evaluate consumer’s preferences regarding packaged milk consumption.

97% of tested milk samples were observed to have added solids and water in them. Chemical adulterants in tetra packaged milk were detected in order of Glucose > cane sugar, Vegetable fat > Formalin, >Artificial colour > Neutralizer > Detergent >Urea, Annatto dye > starch. For the household-based survey, a total of 266 respondents were interviewed. Although 61.7% of respondents preferred pasteurized milk, potential customer satisfaction with the quality of pasteurized milk was 74.4%. Multivariate analysis showed that customer satisfaction regarding pasteurized milk was significantly associated with the preference of customer [Odds Ratio (OR)=4.18, p=0.004], buying factors like price, offers, and discounts (OR=6.92, p=0.014), quality and availability (OR=4.81, p=0.003), and experienced negative health effects (OR=0.26, p=0.002).

The study concluded that more than 70% of the packaged milk samples were adulterated with detergents, artificial flavors and glucose which signify the compromised quality of the packaged milk and their products. Strict regular quality checks should be established and closely monitored by regulatory authorities and the government.

In this study, aiming to solve the problem of difficult recovery of powder catalysts in the treatment of antibiotic wastewater by photocatalytic technology, titanium dioxide nanotubes (TiO2 NTs) photoelectrodes were prepared on titanium sheet substrates by anodic oxidation method.

The precious metals Pd and Ag were introduced to be co-deposited, which realized the effective transfer of photogenerated electrons between the semiconductor and the precious metals and remarkably improved the photoelectrocatalytic activity of the photoelectrodes.

The experimental results showed that the prepared Pd/Ag/TiO2 NTs composite photoelectrode achieved a removal efficiency of 79.51% for tylosin (TYL) within 240 min, which was significantly better than that of the pure TiO2 NTs (1.42-fold) and Ag/TiO2 NTs (1.05-fold) photoelectrodes. Electrochemical analyses demonstrated that the loading of Ag and Pd on the surface of TiO2 NTs can effectively promote the transport and separation of photogenerated charge carriers, thus improving the photoelectrocatalytic performance. In addition, the degradation process of TYL and the dynamic changes of intermediates were deeply analyzed with the help of three-dimensional fluorescence spectroscopy (3D EEMs) and two-dimensional correlation spectroscopy (2DCOS) techniques.

This study provides not only an expanded application of solid catalysts in photoelectrocatalytic treatment of antibiotic wastewater but also new insights for further investigation of the co-deposition of precious metals to improve photoelectrodes.

In this study, the contents of essential and non-essential elements in the sugary and sugar-free varieties of aromatic coffees produced in Turkey were decided, and the effect of sugar addition was examined.

For this purpose, essential (Mg, Se, B, Na, Ca, K, Co, Cr, Fe, Cu, Mn, Mo, P and Zn) and non-essential (As, Ba, Al, Cd, Ti, Ni, Sb and Pb) element contents of the aromatic coffees (sugary and sugar-free) (Classic, Gum Mastic, Gum Mastic Turkish Coffee, Hazelnut, Caramel and Turkish Coffee) supplied from a single brand were detected by using ICP-OES. The effects of the elements taken into the body by the consumption of coffee varieties on health and how much of an individual’s daily requirements are met were investigated. Thus, the place and importance of coffee consumption in nutrition have been determined. For coffee consumption of 3 cups, the intake amounts of selected elements were calculated. Furthermore, a risk assessment study was performed by utilizing the non-essential element concentrations of selected coffees.

Experimental results showed that K is the most ample essential element in all types of coffee, and it has been proven that K ingestion encounters the daily requirement of 1% to 2% for adults.

According to the risk assessment results, the hazard index was calculated for 3 cups of each coffee type intake as less than 1, and these coffees may be classified in the low-risk group.

Ubrogepant is a regulated peptide receptor antagonist associated with the calcitonin gene, granted approval in the United States for the specific treatment of migraine headaches.

An impurity found in the alkali hydrolysis of drug dosage forms has a structure very similar to that of ubrogepant. This research aims to characterize this analogous impurity utilizing NMR and LC-MS spectroscopy tools. Moreover, it is critical to develop an extremely sensitive and superior resolution analytical procedure for identifying and determining the amount of analogous impurity in pharmaceutical products.

The ubrogepant impurity was identified using an optimized chromatographic method that relies on reversed-phase HPLC with UV detection. This technique utilized a charged surface hybrid (CSH) technology column operating in gradient elution mode. A mixture of A-channel (0.1% trifluoroacetic acid) and B-channel (acetonitrile and water, 80:20% v/v) constituted the eluent. The analogous impurity was isolated through fraction collection, purified using flash chromatography, and characterized using NMR (1D and 2D) and LC-MS.

The analogous impurity was successfully separated from the ubrogepant peak with a resolution above 2.0. The concentration of the impurity was approximately 10% compared to the ubrogepant peak after alkaline stressing at room temperature for 30 minutes. NMR (1D 13C NMR and 1H, 2D HMBC, HSQC, NOESY, and COSY) and LC-MS analysis characterized the ubrogepant impurity, revealing it to be an epimer of ubrogepant. The developed approach was highly sensitive, allowing for the quantification of the ubrogepant impurity even at a concentration of 0.2 µg/mL.

The approach demonstrated a remarkable degree of precision, linearity, specificity, and accuracy. This new impurity deserves special attention because of its striking similarity to the active ingredient, ubrogepant.

PYX-201 is an Antibody-Drug Conjugate (ADC) composed of a fully human IgG1 antibody, a cleavable linker mcValCitPABC, and toxic auristatin payloads Aur0101, with a drug antibody ratio (DAR) of approximately 4. PYX-201 is a promising candidate for oncology treatment because it targets the extra domain B splice variant of fibronectin (EDB + FN), which is expressed at low levels in normal adult tissues while at moderate or high levels in various human solid tumors.

An electrochemiluminescence (ECL) immunoassay was developed and validated for the detection (screening, confirmatory, and titration) of antibodies to an ADC PYX-201 in human plasma. Anti-PYX-201 antibodies were captured by biotinylated PYX-201 (Bio-PYX-201) and detected by ruthenylated PYX-201 (Ru-PYX-201) on a Meso Sector imager S 600 or 6000 reader.

The screening cut-point factor (SCPF), confirmatory cut-point (CCP), and titration cut-point factor (TCPF) were found to be 1.11, 20.7%, and 1.23, respectively. Sensitivity was determined to be 2.25 ng/mL in the screening assay and 5.34 ng/mL in the confirmatory assay for anti-PYX-201 antibodies. Sensitivity was determined to be 7.70 ng/mL in the confirmatory assay for anti-PYX-201 monoclonal antibody (mAb) antibodies. The positive controls (PCs) were set at the following levels: low positive control (LPC) at 14.0 ng/mL, medium positive control (MPC) at 100 ng/mL, and high positive control (HPC) at 5,000 ng/mL. The drug tolerance was up to 200 µg/mL at the HPC level, up to 100 µg/mL at the MPC level, and 0 µg/mL at the LPC level. The intra-assay percent coefficient of variation (%CV) was ≤ 4.5% for PCs in the screening assay and ≤ 11.5% for PCs in the confirmatory assay. The inter-assay %CV was ≤ 13.6% for PCs in the screening assay and ≤ 19.2% for PCs in the confirmatory assay. No hook effect, hemolysis effect, or lipemia effect was found in this ADA method. Anti-PYX-201 antibodies were found stable in human plasma for at least 24 hours at room temperature or after six freeze/thaw cycles.

Anti-PYX-201 ADA bioanalytical method validation was reported for the first time in any biological matrix. This ADA method has been successfully applied to human sample analysis to support a clinical study.

Venetoclax is a selective inhibitor of the prosurvival protein BCL-2 approved by the Food Drug Administration in 2016, restoring the apoptic ability of malignant cells. In this study, a fast, highly accurate and precise HPLC method was developed for the analysis of Venetoclax in human plasma.

The optimization of the method was investigated according to Box-Bhenken Design combined with 3D surface methodology. The chromatographic separation was performed in gradient mode with an Ascentis Express C8 column (2.7 μm, 4.6 mm × 10 cm). Agomelatine was used as an internal standard to increase accuracy. The method was completely validated according to ICH guideline M10 bioanalytical method validation. Additionally, the greenness of the method was scaled with NEMI, Analytical Ecoscale, AGREE, and GAPI greenness metrics.

The method was linear in the range of 1.67-12.50 µg/mL with a calculated R² of 0.99; LOD and LOQ were 0.34 µg/mL and 1.02 µg/mL, respectively. The recovery was in the range of 102.6% to 99.08%, and with an RSD% of less than 1.00%. The analytical eco scale and AGREE score of the current method were 85 and 0.55, respectively.

The approach that was developed herein exhibits green, rapidity, high levels of accuracy and precision, cost-effectiveness, and ease of use in the context of clinical and pharmacokinetic investigations.

The Iraqi ecosystem, particularly in the southern area, has been polluted due to human activity. Analyzing biological materials is the most common method for detecting the presence of toxic substances in the human body.

Heavy metal levels of Pb, Ni, and Cd in urine specimens collected from individuals with renal failure and healthy individuals residing in Al-Muthanna province were measured by using atomic absorption spectroscopy. Urine Specimens were collected from two cohorts of male and female participants: the group of individuals with renal failure and the group of individuals who are in good condition. The specimens of urine from both the group of patients with renal failure and the group of healthy individuals were taken from the Al-Muthanna governorate in southern Iraq. This governorate served as a focal point for extensive military operations throughout the Gulf War.

The concentrations of toxic substances (Pb, Ni, and Cd) in the urine specimens of the cohort of patients suffering from renal failure are 0.411, 0.197, and 0.113 mg/l, respectively. Concentrations of (Pb, Ni, and Cd) in the healthy group are 0.249, 0.101, and 0.0294 mg/l, respectively. The toxic metals found in urine samples can be organized in the following order: Pb > Ni > Cd.

The findings indicated that the concentrations of toxic substances in specimens of urine from individuals with renal failure are considerably greater than those in the control group of healthy individuals. According to the findings, patients' incidence of renal failure may be related to the prevalence of harmful compounds in southern Iraq.

4-n-butylresorcinol (4nBR) was widely used in the treatment of chloasma and skin whitening cosmetics. As a decolorizing agent, it can effectively control the activity of tyrosinase. Market regulatory authorities require truthful labeling of ingredients in cosmetics. Therefore, the quantitative determination of 4nBR is of great practical significance.

At present, the main detection method of 4nBR reported in the literature is HPLC.Compared with the HPLC method, optical methods offer several advantages, including low cost, and simplicity, which make them suitable for on-field detection applications. A convenient spectrophotometric method was established for 4nBR detection.

Fe³⁺ can oxidize the common colorless chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxTMB. Based on the fact that 4-n-butyl resorcinol (4nBR) can reduce oxTMB, a convenient and rapid spectrophotometric method for the determination of 4nBR was proposed.

Under the optimum conditions, the absorbance at 652 nm has a good linear relationship with the concentration of 4nBR in the range of 1.2 - 16 μM. The linear equation for the detection of 4nBR was ΔA = 0.0546 c (μM) - 0.0026 (r²=0.9962), and the detection limit was 0.33 μM. The accuracy of this method is comparable to that of HPLC.

This method has good selectivity for 4nBR and good anti-interference ability for common additives in cosmetics. The proposed method can be applied to the determination of 4nBR in thereal samples.

Due to the segregation of lightweight aggregate concrete, there is a phenomenon of uneven distribution of ceramsite (aggregate) in commercial ceramsite concrete, lightweight wallboard, which the specific performance of wallboard can reflect.

In this paper, the non-uniformity of six commercial ceramsite concrete wallboards with different curing conditions was analyzed. Six wallboards were cut into 648 samples and photographed, and ImageJ image analysis technology was combined to analyze the non-uniformity of the ceramsite concrete wallboard under different curing conditions in terms of the proportion of ceramsite particle area, density, compressive strength, and ultrasonic velocity. At the same time, the reasons for the difference in wallboard performance under different curing methods were explained from the microscopic perspective by investigating the ITZ interface.

Compared with natural curing, sealing curing can significantly optimize the performance distribution of the wallboard and effectively improve the inhomogeneity of the wallboard. The average density of the specimen is increased by about 13%, and the average compressive strength by about 20%. The maximum density of the wallboard samples is increased by 105 kg/m³, which is about 15% higher than that of the naturally cured wallboard.

This paper quantifies the magnitude of the effect of sealing curing on wallboards and provides a basis for the selection of curing methods for ceramsite concrete wallboards.

This is the first report on the development and validation of thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC)-densitometric methods for the identification of linoleic acid (LA) in petroleum ether extract (PEE) of Euphorbia neriifolia (EN) stem (ST), latex (LX), and bark (BA).

Chromatographic analyses were performed on silica gel-G and silica gel 60 F254 plates and the antioxidant activities of isolated compounds were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) spectrophotometric assay.

The chromatographic analyses revealed better spots and well-separated peaks of LA with retention factor (Rf) values at 0.54 (ST), 0.40 (LX), and 0.64 (BA), respectively. The linearity of the calibration curve ranges from 10-50 ng/spot (ST), 10-100 ng/spot (LX), and 50-200 ng/spot (BA). The proposed method was characterized by better accuracy, better robustness, and good precision, ranging from 0.173 to 0.372% (intra-day) and 0.185 to 0.205% (inter-day). The value of the limit of detection and quantification equal to 1.04 and 3.16 ng/spot in ST, 0.87 and 2.64 ng/spot in LX, and 0.177 and 0.53 ng/spot in BA determined the sensitivity of the method. In the obtained chromatogram, no peak was observed other than the LA which determined the specificity of the method. The % RSD of < 2% after periods of 12, 24, 36, 48, and 72 h determined the stability of standard LA.

Thus, the fingerprinting method is valuable in determining the adulterants and in routine quality control of formulations and herbal drugs.

This study describes the development of methodologies for the isolation, identification, and quantification of betulinic, oleanolic, and ursolic acids in extracts from Eriope blanchetii (Lamiaceae) and Davilla rugosa (Dilleniaceae).

Betulinic, oleanolic, and ursolic acids are compounds with biological activities and commercial and technological uses. Developing methodologies for their separation from natural sources are relevant once their synthesis is not easy.

Development of conventional methodology for quantifying and isolating pure betulinic acid in chloroform extracts of D. rugosa stems and developing methods for obtaining and quantifying oleanolic, ursolic, and betulinic acids from organic extracts.

A complete validation “in-house” for the chromatographic method was performed, and different techniques of extraction – maceration under heating vs. microwave-assisted extraction (MAE) conditions were compared. Davilla rugosa stems were employed as the source of pure betulinic acid, and this compound was obtained in a reasonable yield (~ 2.4 x 10^-2% dry weight).

Chromatographic analysis of the E. blanchetii extracts indicates betulinic acid occurs in higher concentrations in the leaves (5.53% dry weight), followed by lower concentrations in other plant parts, together with two other triterpene acids. HPLC analysis of extracts obtained by MAE extractions and maceration of E. blanchetti indicated that MAE is more efficient than maceration under heating in relative yield. The HPLC-validated method was rightly selective and accurate, presenting good linearity (R² = 0.9993), robustness, and recovery rate values with acceptable limits (LD = 5.9914; LQ = 18.1557; µg mL^-1).

MAE was the most efficient methodology than maceration under similar conditions. Furthermore, different parts of E. blanchetii and D. rugosa are affordable sources of bioactive betulinic acid.

The recognition of the health hazards of azo dyes has highlighted the need to develop efficient, rapid, and reliable analytical methods for dye determination.

In this work, electrochemical probing of the azo group of Tartrazine (TZ) and Carmoisine (CR) in food dyes was carried out. Synthesized bismuth and zinc oxide nanoparticles were used to modify Graphite Electrode (GE).

Electrochemical analysis showed a much better electrochemical response using ZnO+Bi/GE as a modifier than individually nanoparticle-modified graphite electrodes. From the CV analysis, it was found that both the dyes exhibited irreversible electrochemical behavior, and the redox parameters were calculated. The Limit of Detection (LOD) values recorded for TZ and CR for ZnO+Bi/GE-based sensors were 0.84 µM and 2.80 µM, respectively. The obtained sensitivity values were 11.86 µA/µM/cm² for TZ and 17.3 µA/µM/cm² for CR.

The sensor evidently demonstrated reliable simultaneous detection of both dyes, making it suitable for practical applications in food safety analysis.