Graded-index Research Articles

Systemic inflammatory markers: Predictors of survival in mucinous appendix cancer patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

IntroductionInflammatory markers have been investigated as predictors of prognosis in various malignancies, but their role in mucinous appendix cancer (MAC) remains controversial. We evaluated the association between complete blood count-derived markers and survival in MAC patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). MethodsWe conducted a retrospective analysis of a single-center database (1998–2023) including newly diagnosed MAC patients who underwent complete (CC-0/1) CRS/HIPEC. Preoperative values of neutrophil-to-lymphocyte ratio (NLR), derived NLR, platelets-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) were calculated. For markers strongly associated with survival, we used time-dependent ROC analysis to define cutoffs to predict 5-year overall survival (OS). The Kaplan-Meier method with and Cox regression were employed for survival analysis. ResultsOf 626 CRS/HIPEC cases, 211 were eligible. NLR (p=0.049), dNLR (p=0.049), and MLR (p<0.001) were significantly associated with OS, while PLR was not. MLR demonstrated the strongest prognostic power (AUC=0.682) with the optimal cut-off 0.29. There were no significant differences in age, grade, or peritoneal cancer index (PCI) between patients with MLR<0.29 and MLR≥0.29. Five-year progression-free (PFS) and OS were 72.2 % and 83.2 % for MLR<0.29 and 54.2 % and 66.6 % for MLR≥0.29, respectively. After adjusting for age, PCI, and grade, MLR≥0.29 was associated with worse 3-year PFS (hazard ratio [HR] 1.74, 95 % confidence interval [CI]:1.02–2.97, p=0.044) and 3-year and 5-year OS (HR 1.87, 95 %CI: 1.00–3.47, p=0.049). ConclusionMLR has emerged as an independent predictor of survival in MAC patients undergoing CRS/HIPEC. Along with other prognostic factors, MLR≥0.29 may be potentially used for preoperative risk stratification.

Spectrophotometric determination of zinc in blood and food samples using an air-assisted rapid synergistic-cloud point extraction method based on deep eutectic solvents

At room temperature, an air-assisted rapid synergistic cloud point extraction (AA-RS-CPE) method based on deep eutectic solvent (DES) was presented to determine Zn (II) traces in various samples. Nonanoic acid and L-menthol formed the synergistic reagent (DES) in a 2:1 mole ratio to reduce both time and cloud point temperature. Air cycles were used to maximize recovery and accelerate cloudy solution formation. The 4,4-dimethyl-2,6-dioxo-N-phenylcyclohexanecarbothioamide (DDPCCTA) and TritonX-100 were used as ligand and surfactant, respectively. The validation parameters, including the calibration curve linearity (0.2-900µgL-1), the limit of detection (LOD = 0.10µgL-1), the enhancement factor (EF = 120), and the preconcentration factor (PE = 100), were calculated. Additionally, the accuracy of the AA-RS-DES-CPE approach was proved by two certified reference materials (CRMs). Finally, the three greenness tools, the Blue Applicability Grade Index (BAGI), the Sample Preparation Metric of Sustainability (SPMS), and the Analytical Greenness Metric for Sample Preparation (AGREEprep), were used to evaluate the environmental sustainability values, health hazards, and applicability of this method. This approach was improved to be safer and more environmentally friendly than existing methods, with high application potential.

Rapid green analytical methodology for simultaneous monitoring of nitrosamines and semi-volatile organic compounds in water and human urine samples.

Nitrosamines and semi-volatile organic compounds (SVOCs) are carcinogenic contaminants in water and biological matrices. Conventional analytical methods often struggle to detect trace concentrations due to poor extraction efficacies. This study presents a novel, low-cost, in-syringe-assisted fast extraction cum cleanup technique coupled with GC-FID for monitoring four nitrosamines and two SVOCs in drinking water and human urine samples to measure the contamination and exposure levels. This extraction protocol combines a novel green in-syringe liquid-liquid extraction step using dimethyl carbonate as the green extraction solvent, coupled with a semi-automated solid-phase extraction cleanup process. Then, the final extractant is analyzed using gas chromatography-flame ionization detection (GC-FID) for monitoring. The method demonstrated excellent linearity (R2 > 0.998) between 1.5 and 500ngmL⁻1 for all six target compounds. Detection limits ranged from 1.0 to 2.0ngmL⁻1. Extraction recoveries were between 87 and 105% for both urine samples and water samples. Intra-day and inter-day precision were below 9% RSD. The blue applicability grade index evaluation scored 70.0, indicating good practical applicability. The developed analytical protocol offers a sensitive, accurate, low-cost, rapid, and environmentally friendly method for simultaneously quantifying multiple nitrosamines and SVOCs in environmental and human samples. Its performance characteristics and sustainability metrics suggest the potential for broad application in monitoring and exposure studies.

Efficient integration of analytical quality-by-design and tri-hued HPLC-DAD approach for synchronized assessment of gemigliptin and rosuvastatin in their fixed-dose pills: Application to stability study

Life-threatening atherosclerotic cardiovascular disorder is a well-recognized risk among diabetics, which is clinically ascribed to their unbalanced plasma lipoproteins. Gemigliptin-Rosuvastatin is a recently introduced polytherapy prescribed for the management of diabetic dyslipidemia. Currently, the main focus of several analysts is to design more ecologically friendly sustainable approaches for pharmaceutical analysis. In this context, an innovative tri-hued (green, blue, and white) stability-indicating HPLC-DAD approach was developed to concurrently quantify Gemigliptin and Rosuvastatin polypills. Consequently, a strategic integration between analytical quality-by-design and green/white analytical chemistry principles was specifically designed to optimize efficiency and practicality while minimizing ecological burden. Two experimental designs, namely two-level fractional factorial and Box-Behnken designs, were employed for screening and optimization procedures, respectively. Optimal separation was attained utilizing an Agilent HC-C18 column in conjunction with a mobile phase consisting of acetonitrile and 10 mM sodium dihydrogen phosphate buffer, pH 3 (60:40 v/v), eluted in an isocratic manner at a 1 mL/min flow rate. Both analytes exhibited good linearities within the concentration range of 0.5–100 μg/mL. Furthermore, stability studies were conducted on both drugs in response to variable stress degradation scenarios. Fortunately, the adopted approach was well-suited to resolve the studied drugs from their respective degradants, thereby verifying the method's stability-indicating power. Tri-hued evaluation for the implemented approach was performed via up-to-date metrics, specifically, the Analytical Eco-scale, AGREE, Blue Applicability Grade Index, and RGB 12. Ultimately, our adopted stability-indicating HPLC approach exhibited great sensitivity, specificity, applicability, and rapidity as well as being ecologically sound. It is worth noting that this is the first stability-indicating HPLC approach for simultaneous assessment of the studied drugs.

A cutting edge potentiometric determination of baricitinib in synthetic wastewater and in tablet dosage form using modified carbon paste ion-selective membrane

After the recent hit of COVID-19, many drugs were successively administered to save patients’ lives and those drugs reached aquatic sources, one of those drugs was Baricitinib. Driven by the current situation, a potentiometric technique using an ion-selective membrane (ISM) recipe drop cast on a modified carbon paste electrode was optimized for the superior determination of Baricitinib (BAR). The molecular docking was customized to optimize the proper ionophores incorporated in the ISM, revealing that beta-cyclodextrin (β-CD) is the most compatible ionophore with the studied drug. A multivariate optimization experimental design was employed to optimize the best experimental condition for the analytical method. To this end; dual nanoparticles (multi-walled carbon nanotubes and copper oxide nanoparticles) were incorporated in the carbon paste electrode, and the ISM recipe was enriched with β-CD and cation-exchanger (phosphotungstic acid) in a polyvinylchloride matrix plasticized with dibutyl phthalate. A Nernstian slope equal to 19.97 mV/decade with a linearity range of 7.99 × 10−7–1.00 × 10−3 M was obtained. The validated sensor exhibited good recovery when used to determine the studied drug in synthetic wastewater and tablet dosage form. The greenness of the method was evaluated using the Complementary Green Analytical Procedure Index and Blue Applicability Grade Index.

Impact of porosity on free vibration and limit analysis of power-law-based functionally graded disks

PurposeThis study aimed to analyze the free vibration of a radially graded Ni-Al2O3-based functionally graded (FG) disk with uniform thickness.Design/methodology/approachUsing the energy method, natural frequencies of rotating and non-rotating disks were determined at the limit elastic angular speed. Material properties were estimated using a modified rule of mixture. Both even and uneven porosity variation effects were considered in the material modeling. Finite element analysis validated the analytical approach.FindingsThe study explored limit angular speeds and natural frequencies across various grading indices, investigating the impact of porosity types and grading indices on these parameters.Practical implicationsInsights from this research are valuable for researchers and design engineers involved in modeling and fabricating porous FG disks, aiding in more effective design and manufacturing processes.Originality/valueThis study contributes to the field by providing a comprehensive analysis of free vibration behavior in radially graded Ni-Al2O3-based FG disks. The incorporation of material modeling considering both even and uneven porosity variation adds originality to the research. Additionally, the validation through finite element analysis enhances the credibility of the findings.

Rapid UV-Vis spectrophotometric method aided by firefly-PLS models for the simultaneous quantification of ciprofloxacin, lomefloxacin, and enrofloxacin in their laboratory mixture, dosage forms and water samples: greenness and blueness assessment

Herein, a novel UV spectrophotometric method coupled with chemometric tools was developed for the simultaneous determination of three fluoroquinolone antibiotics: ciprofloxacin, lomefloxacin, and enrofloxacin. Such integration of UV spectroscopy and chemometric analysis proved to be a simple, rapid, and cost-effective approach for the quantification of these clinically important pharmaceutical compounds and aid in their quality control analysis. The method employed firefly algorithm for variable selection and partial least squares (PLS) regression for model calibration. The developed method was validated by independent test set in addition the accuracy, intra and inter-day precision as per ICH guidelines which showed a satisfactory performance with mean recovery ranged between 98.18 and 101.83 with %RSD < 2. Besides, the developed method displayed ultrasensitive levels with LODs (0.0803, 0.1125, 0.1309 µg/mL) and LOQs (0.2434, 0.3409, 0.3968 µg/mL) for ciprofloxacin, lomefloxacin, and enrofloxacin, respectively. The greenness and blueness of the developed method were also evaluated using the recently proposed Analytical GREEnness metric approach (AGREE) and Blue applicability grade index (BAGI) tools, which showed a high AGREE score of 0.79 and a BAGI score of 77.5. These results indicate that the developed method provides an environmentally friendly alternative to the traditionally used chromatographic techniques, while maintaining high analytical practicability. Finally, the application of the developed methodology was demonstrated on real pharmaceutical and tap water samples, and the results were in good agreement with those obtained by the reference HPLC method indicating the reliability and suitability of the proposed spectrophotometric method for routine analysis of fluoroquinolone antibiotics.

Application of zwitterionic ionic liquid-based capsule phase microextraction for the HPLC-UV determination of doxycycline in human urine samples

Herein, we describe the utilization of an ionic liquid (IL)/Carbowax 20 M−functionalized sol–gel sorbent for the capsule phase microextraction of doxycycline in authentic human urine samples. This green sample preparation method combines stirring and filtration in a single, standalone sample preparation device, streamlining the sample preparation process. Additionally, it provides rapid extraction kinetics and high extraction efficiency. The experimental conditions (i.e. sorbent type, sample pH and volume, extraction time, ionic strength, elution solvent, and volume) affecting the extraction efficiency of the analyte were studied and optimized. The method was linear in the range of 0.1 – 5.0 μg/mL with a coefficient of determination higher than 0.995. The achieved LOD was found to be 0.02 μg/mL while the lower limit of quantitation (LLOQ) was 0.1 μg/mL. The IL/Carbowax 20 M−functionalized microextraction capsules were reusable at least 30 times for urine samples. The relative recoveries (% RR) ranged between 93.4 – 115.9 % while the precision (expressed as % RSD) was better than 8.1 % in all cases. The robustness of the microextraction procedure and the instrumental HPLC method were separately investigated using Plackett-Burman experimental designs. The analytical protocol demonstrated cost-effectiveness, ease of handling, and speed, leading to increased sample throughput. The green character of the developed method was evaluated using the Green Analytical Procedure Index (GAPI) and Blue Applicability Grade Index (BAGI). Finally, the method’s applicability was demonstrated by analyzing authentic human urine samples after oral administration of a doxycycline-containing pharmaceutical formulation.

Innovative UPLC technique for concurrent quantification of etofenamate and benzyl nicotinate in the presence of methylparaben and benzyl alcohol in their topical cream: Greens, white, and Six Sigma methodologies.

The efficacious treatment of muscle and joint pain relies heavily on etofenamate (ETO) and benzyl nicotinate (BN), which possess robust anti-inflammatory and pain-relieving properties when paired with methylparaben (MP) or benzyl alcohol (BA). In this study, we have established and validated innovative RP-UPLC methods for assessing ETO and BN in the presence of MP or BA in their dosage forms, employing eight green tools to evaluate their eco-friendliness and effectiveness. Reversed phase-ultra-performance liquid chromatography (RP-UPLC) technique employs a flow rate of 0.3mL/min on Waters Acquity UPLC BEH Column (C18, 1.7μm, 100 mm × 2.1mm), detection at 254 nm using a photo diode array (PDA) detector and mobile phase of 0.05 M KH2PO4 buffer, acetonitrile, and methanol (50:15:35, v/v/v) adjusted pH6.0 with 0.2% triethylamine. For ETO, BN, MP, and BA, the calibration curves were linear and ranged from 0.005 to 1.0, from 0.001 to 0.2, from 0.002 to 0.08, and from 0.0001 to 0.1mg/mL, respectively. The correlation value was 0.9999, and the accuracy findings ranged from 98.81% to 100.56%. Consequently, the methodology has been successfully implemented in assay testing for the pharmaceuticals in the presence of the MP or BA, demonstrating the high selectivity of these approaches. The present study presents the Blue Applicability Grade Index (BAGI), an innovative approach that complements green metrics in practical white analytical chemistry. According to the International Council for Harmonisation (ICH) criteria, the procedures were effectively validated.

A sustainable HPLC method coupled with diode array detection for versatile quantification of telmisartan, chlorthalidone and amlodipine in a fixed-dose antihypertensive formulation and dissolution studies

Cardiovascular diseases, especially hypertension, stand as prominent contributors to global mortality. Hypertension, often referred to as a silent killer syndrome, necessitates the use of multiple medications for effective control and management. A new environmentally friendly HPLC–DAD method is introduced in this study for the concurrent analysis of telmisartan (TEL), chlorthalidone (CHT) and amlodipine besylate (AML), in both pure forms and combined pharmaceutical dosage form. An isocratic elution mode was employed to achieve chromatographic separation, utilizing an Inertsil C18 column (250 × 4.6 mm, 5.0 µm) and a mobile phase mixture of acetonitrile and phosphate buffer (pH 3.0 ± 0.1) with ratio of 35:65, v/v. The separation was achieved within 10 min at a flow rate of 1.0 mL/min. The proposed method's validation was carried out following the guidelines outlined by the International Council for Harmonisation (ICH). The achieved linearity range was 1.0–140.0 μg/mL for TEL and 1.0–100.0 μg/mL for CHT and AML with quantification limits of 0.061, 0.177, and 0.313 μg/mL for TEL, CHT, and AML, respectively. The fixed combination tablet dosage form demonstrated acceptable release profile, as indicated by the in-vitro dissolution studies. The studied dissolution media were phosphate buffer pH 7.5, 0.01 N HCl, and water, utilizing a USP type II apparatus at 37 ± 0.5 °C with a stirring rate of 75 rpm. The proposed method was applied successfully for the quality assessment of Telma-ACT® Tablets with good precision and accuracy. Various tools were used for evaluating the level of greenness, including Green Analytical Procedure Index (GAPI), Analytical Greenness Metric for Sample Preparation (AGREEprep), Analytical Eco-Scale (AES), and Analytical Method Greenness Score (AMGS). These tools had confirmed the eco-friendliness of the proposed method. Additionally, the newly introduced White Analytical Chemistry (WAC), and the Blue Applicability Grade Index (BAGI) have been specifically developed to evaluate the sustainability and the applicability of the method.

Selective microextraction of erythrosine (E127) in foodstuffs using a new generation high-density type-V deep eutectic solvent

A novel and selective (deep eutectic solvent) DES-based microextraction method was established for the first time, utilizing a synthesized new generation High-Density Type-V DES for monitoring the dye Erythrosine (E127) in various foodstuffs and drugs. Type-V DES was created from acetophenone and diphenylamine at 3:1 M ratio. The pH, DES amount, and vortex time were optimized using Box-Behnken Design (BBD) of Response Surface Methodology (RSM). The quadratic microextraction model with R2 = 0.9982 was obtained. The limit of detection, preconcentration factor and linear dynamic range were determined to be 12 μg/L, 50 and 41–4000 μg/L, respectively. Effects of matrix components were examined. The developed High-Density Type-V Deep Eutectic Solvent Microextraction (HD-V-DES-ME) method was applied to foodstuffs and drugs to monitor their E127 contents and subsequently validated by applying spiked tests to real samples, with recoveries ranging between 94 and 101 %. The indexes of environmental friendliness and practicality for the method were evaluated using the Analytical GREEnness metric approach tool (AGREE) and the Blue Applicability Grade Index tool (BAGI), respectively.

New method for the investigation of mode coupling in graded-index polymer photonic crystal fibers using the Langevin stochastic differential equation

The mode coupling in a graded-index polymer photonic crystal fiber (GI PPCF) with a solid core has been investigated using the Langevin equation. Based on the computer-simulated Langevin force, the Langevin equation is numerically integrated. The numerical solutions of the Langevin equation align with those of the time-independent power flow equation (TI PFE). We showed that by solving the Langevin equation, which is a stochastic differential equation, one can successfully treat a mode coupling in GI PPCFs, which is an intrinsically stochastic process. We demonstrated that, in terms of effectiveness, the Langevin equation is preferable compared to the TI PFE. The GI PPCF achieves the equilibrium mode distribution (EMD) at a coupling length that is even shorter than the conventional GI plastic optical fiber (POF). The application of multimode GI PCFs in communications and optical fiber sensor systems will benefit from these findings.

Low-complexity turbulence resilience enabled by a multi-mode bi-directional transceiver

Free-space optical (FSO) communication systems are acutely affected by the pointing issues and distortions that result from mechanical instability and environmental factors such as turbulence. These distortions have generally prevented single-mode bi-directional systems from being deployed without adaptive optics due to high optical losses. We investigate and compare the performance of both step and graded index multi-mode fibers for bi-directional communications over an emulated 400 m FSO channel. We propose that OM5 graded index fiber will simultaneously provide a near Gaussian optical transmission mode and a factor of greater than 5 increase in the field of view compared to single-mode fiber. We demonstrate that OM5 can support an error-free throughput of 10 Gbps for low-turbulence (D/r0 = 3) and 9.1 Gbps for high-turbulence (D/r0 = 9) using commercial bi-directional small form-factor pluggable (SFP+) transceivers with no adaptive optical components.

Optimal design of broadband, low-directivity graded index acoustic lenses for underwater communication.

Manipulating underwater pressure waves is crucial for marine exploration, as electromagnetic signals are strongly absorbed in water. However, the multi-path phenomenon complicates the accurate capture of acoustic waves by receivers. Although graded index lenses, based on metamaterials with smoothly varying properties, successfully focus pressure waves, they tend to have high directivity, which hinders practical application. This work introduces three 2D acoustic lenses made from a metamaterial composed of solid inclusions in water. We propose an optimization scheme where the pressure dynamics is governed by Helmholtz's equation, with control parameters affecting each lens cell's density and bulk modulus. Through an appropriate cost function, the optimization encourages a broadband, low-directivity lens. The large-scale optimization is solved using the Lagrangian approach, which provides an analytical expression for the cost gradient. This scheme avoids the need for a separate discretization step, allowing the design to transition directly from the desired smooth refractive index to a practical lattice structure. As a result, the optimized lens closely aligns with real-world behavior. The homogenized numerical model is validated against finite elements, which considers acoustic-elastic coupling at the microstructure level. When homogenization holds, this approach proves to be an effective design tool for achieving broadband, low-directivity acoustic lenses.

Optimized reversed phase liquid chromatography methodology for the determination of vonoprazan fumarate impurities: Towards Six Sigma quality standards and sustainability assessment

Vonoprazan fumarate (VPZ), a potent potassium-competitive acid blocker, holds great promise as a therapeutic option for addressing acid-related disorders. This study introduces a refined reversed phase liquid chromatography methodology tailored for the comprehensive analysis of eight related substances, including starting materials, byproducts, and degradants within VPZ. Our approach integrates response surface methodology and tolerance analysis to achieve six sigma quality standards in chromatographic performance. By embedding specifications into the optimization process, we ensure robustness during method development. Chromatographic separation was executed using an XSelect CSH Phenyl-Hexyl column under stepped gradient conditions, employing a mobile phase comprising 0.1 % trifluoroacetic acid aqueous solution and acetonitrile. The flow rate was maintained at 1.3 mL/min, with UV absorbance at 252 nm, and a column temperature set at 25 °C. To evaluate the stability indicating ability of the method, forced degradation studies were conducted. Importantly, identified degradants did not interfere with the accurate quantification of VPZ and its associated impurities. Validation of the method was achieved through accuracy profiles. A greenness assessment was conducted using National Environmental Methods Index (NEMI), carbon footprint analysis, Analytical Greenness Calculator (AGREE), and Complementary Green Analytical Procedure Index (Complex GAPI). Additionally, blueness and whiteness assessments were conducted using the Blue Applicability Grade Index (BAGI) and Red-Green-Blue 12 (RGB 12) algorithms, respectively. The proposed method exhibited a green profile in NEMI and Complex GAPI. The carbon footprint was calculated at 0.055 kg CO2 equivalent per sample. The AGREE score was 0.67, BAGI was 80.0, and the whiteness score from the RGB12 algorithm was 83.5.This methodological framework holds promise for utilization in process development and quality assurance of VPZ in bulk drug manufacturing, particularly in the absence of official monographs within recognized compendia.

Μagnet integrated fabric phase sorptive extraction (MI-FPSE) for the selective isolation of seven sulfonamides from human urine prior to HPLC-DAD analysis

In the present study magnet integrated fabric phase sorptive extraction (MI-FPSE) was employed for the selective extraction of seven sulfonamides (i.e., sulfamerazine, sulfamethazine, sulfamethoxypyridazine, sulfamonomethoxine, sulfamethoxazole, sulfisoxazole and sulfadimethoxine) from human urine prior to their determination by high pressure liquid chromatography – diode array detection (HPLC-DAD). The MI-FPSE protocol was optimized after studying the critical parameters that affect extraction, namely: type of sol–gel sorbent, extraction time, desorption time, stirring rate, type and volume of elution solvent, the ionic strength and the pH of the sample matrix using the one-factor-at-a-time method. The developed MI-FPSE-HPLC-DAD method was validated in terms of linearity, sensitivity, selectivity, accuracy, and precision and presented satisfactory results. The limits of detection (LODs) and quantification (LOQs) ranged between 0.02–0.04 ng/μL and 0.06–0.15 ng/μL, respectively. The RSD% values of the intra-day and inter-day assays were found lower than 6.7 % and 9.4 %, respectively, showing good precision. Accuracy was assessed using percentage of relative recovery and varied from 86.3–112.9 % (intra-day study) and 85.5–106.9 % (inter-day study) for all examined analytes. The green character and practicality of the proposed method were investigated using the ComplexGAPI index and Blue Applicability Grade Index (BAGI).

CREC Optical-Fibre Sensors for Hydrodynamic Studies in Gas−Solid Fluidized Beds

Optical probes can be employed in dense and dilute fluidized beds. Their application is useful to determine particle volume fraction, bubble velocity, bubble size, and solid segregation in dense-phase fluidized-bed reactors, as well as particle-cluster velocity, size, and shape, in downer/riser units. The CREC-UWO team has developed a unique and miniaturized CREC Optiprobes System (CREC-GS-OPS) equipped with a GRIN (graded refraction index) lens. The GRIN lens creates a small volume of high light irradiation by focusing a laser a few millimetres away from the front of the probe tip. This design minimizes sensor intrusiveness and, as a result, provides trustworthy measurements of hydrodynamic parameters. Through the application of the CREC-GS-OPS, advances have been achieved, leading to (a) the development of a “Y-back” unit with graphite ferrules that protects the optiprobes from fibre-optic stresses and prevents the loss of sensor calibration and (b) the establishment of statistically-based data analysis. It is envisioned that through the introduction of a few design changes, the CREC Optiprobes will be made suitable for high-temperature applications. This will allow the measurement of catalyst flow recirculation (among other measurements), in industrial-scale fluidized-bed catalytic cracking units involving fluidized riser crackers and catalyst regenerators.

Application of new green evaluation tools to assess the environmental impact of analytical procedures based on solid phase microextraction techniques

In this comparative study, four green evaluation tools, blue applicability grade index (BAGI), Analytical GREEnness (AGREE), Green Analytical Procedure Index (GAPI), and Analytical Eco-Scale were evaluated to assess 16 selected analytical methods including fiber-solid phase microextraction, stir bar sorptive extraction, and thin film microextraction joint to gas and liquid chromatographic as well as spectrofluorimetry techniques. The required parameters and data were extracted from the selected articles and calculations were performed based on the unique evaluation protocol of each tool. A uniform approach was applied in calculations and evaluations. A comparison of selected methods was done by determining the factors affecting greenness. High energy consumption, organic solvents, waste generation, analysis throughput, and the number of determined analytes, are among the crucial parameters that require improvement in the selected methods. The results show that using more than one evaluation tool in evaluating the greenness of analytical methods is very effective in obtaining synergistic results and increasing the understanding of the greenness of analytical methods.

Exploiting the Applicability of Polytetrahydrofuran-Modified Polyester for the Fabric Phase Sorptive Extraction of Doxycycline from Human Urine.

In this report, a polytetrahydrofuran-coated polyester fabric phase sorptive extraction (FPSE) for the determination of doxycycline in human urine was described. The sol-gel polytetrahydrofuran sorbent proved to be superior against other sol-gel coated cellulose and polyester membranes tested. The effect of the extraction parameters including membrane surface area, sample pH and volume, salt concentration, extraction time, stirring rate, etc., on the extraction efficiency of the analyte was studied using the "one-factor-at-a-time" (OFAT) and Box-Behnken design approaches. The analytical method proposed was validated in compliance with FDA guidelines for bioanalytical procedures. The method was linear in the determination range of 100-5000 ng/mL with the determination coefficient of 0.9953. The limit of detection (LOD) and the lower limit of quantification for doxycycline was 17 and 100 ng/mL, respectively. The relative recoveries for intra-day and inter-day studies ranged from 98.5-112.2% and 89.6-96.8%, respectively. The relative standard deviation was lower than 14.7% in all cases, exhibiting good precision. The sol-gel polytetrahydrofuran-modified FPSE membranes were reusable for at least 30 times. The greenness of the developed method was evaluated using Sample Preparation Metric of Sustainability (SPMS) and Blue Applicability Grade Index (BAGI) metric tools. Finally, the analytical scheme was successfully employed for the quantitation of urinary doxycycline collected at various time points following the administration of doxycycline-containing tablets.

Exploring environmental sustainability through dimension reduction algorithms: A cost-effective UV spectroscopic method for simultaneous determination of veterinary binary mixtures of doxycycline hydrochloride and tylosin tartrate

This study presents a cost-effective and environmentally friendly approach for the simultaneous determination of a veterinary binary mixture comprising doxycycline hydrochloride (DOX) and tylosin tartrate (TYZ) utilizing UV spectroscopy alongside dimension reduction algorithms (DRAs). Seventeen DRAs were evaluated, and their performances were compared based on four metrics: mean squared error (MSE), mean absolute error (MAE), median absolute error (MedAE), and coefficient of determination (R2). Based on the performance indices, Isomap algorithm demonstrated the highest predictive capacity among all DRAs. MSE, MAE, MedAE and R2 values of (0.38, 0.28, 0.19 and 0.999) and (0.08, 0.26, 0.22 and 0.998) were obtained for calibration and test datasets, respectively across a concentration range 4.67–30 μg mL−1 for DOX. MSE, MAE, MedAE and R2 values of (0.54, 0.34, 0.19 and 0.994) and (0.07, 0.19, 0.07 and 0.998) were obtained for calibration and test datasets, respectively across a concentration range 3.51–24 μg mL−1 for TYZ. The developed method underwent validation utilizing the accuracy profile approach. An ecological impact assessment was carried out employing six greenness evaluation tools: The Green Solvent Selection Tool (GSST), National Environmental Methods Index (NEMI), the Assessment of Green Profile (AGP), carbon footprint analysis, Analytical Greenness Calculator (AGREE), and Complementary Green Analytical Procedure Index (Complex GAPI). Additionally, we applied blueness and whiteness assessments using Blue Applicability Grade Index (BAGI) and Red-Green-Blue 12 (RGB 12) algorithms, respectively. The proposed method demonstrated higher GSST scores, a more "green" profile in NEMI, a superior AGP profile, and better environmental sustainability in Complex GAPI. The calculated carbon footprint value was 0.0002 kg CO2 equivalent per sample, The AGREE score was 0.87, BAGI was assessed at 72.5, and the whiteness assessment by the RGB12 algorithm was 89.6. Statistical comparison of the proposed method with a previously reported HPLC method for dosage form analysis revealed no significant differences at a 95% confidence level. This study highlights the novelty of combining UV spectroscopy with dimension reduction algorithms, offering significant advancements over traditional UV and chemometric methods for the analysis of these drugs. This approach not only enhances the efficiency and accuracy of determining active ingredients in pharmaceutical dosage forms but also contributes to environmental sustainability.