Natural Reagent Research Articles

A Spectrophotometric Determination of Amlodipine Drug in Pharmaceutical Preparations Using 2, 6-Dihydroxybenzoic Acid Reagent

In this study, a delicate, exact, and efficient colorimetric spectrophotometric technique was created for the assessment of Amlodipine in its unadulterated structure and in drug arrangements The strategy depends on the response of the optional amine in the medication with the carbonyl gathering in the natural reagent 2, 6 dihydroxy benzoic corrosive within the sight of p-dimethyl amino benzaldehyde to frame a yellow complex (Manich complex). The greatest absorbance was viewed as at 402 nm. Linearity was seen in the scope of 2-40 μg/mL, and the connection coefficient was viewed as 0.9909. The molar absorptivity was viewed as 1.392 × 104 L•mol-1•cm-1. It was observed that the shade of the item was steady and no massive change in absorbance was noticed for as long as 50 minutes a recuperation of 100.596% was gotten. The restriction of discovery (LOD) and cutoff of evaluation (LOQ) were viewed as 0.968 µg/mL and 3.228 µg/mL, individually. The %RSD was 4.32, which demonstrates the precision of the proposed strategy.

Reverse Flow Injection Spectrophotometric Determination of Total Acidity in Beverages Using Butterfly Pea Flower Extract.

Monitoring total acidity during beverage production is crucial for quality control (QC). The standard acid-base titration, though widely used, is slow and generates hazardous waste through the use of acid-base indicators. To develop an analysis method for beverage samples to determine total acidity using a natural reagent from butterfly pea flower as the colorimetric reagent. The determination of total acidity in beverages was based on the reaction of citric acid with anthocyanin extracted from butterfly pea flowers. The decreased absorbance of anthocyanin was measured at 620 nm. A two-line reverse flow injection manifold was used to perform online dilution of samples. Under optimal conditions, the calibration curve equation 1/A = 0.03782C + 0.00241 (A = absorbance and C = concentration) was linear over a range of 0.050-0.25% (w/v) citric acid. The LOD and LOQ were 0.0123 and 0.0409% (w/v), respectively. The system achieved a throughput of 120 samples per hour with comparable accuracy and precision to the standard titrimetric method. The injection of butterfly pea flower extract into beverage samples with online dilution in a reverse flow injection system (FIS) was reported for the first time for the determination of total acidity. Use of a green reagent in the method reflects its alignment with the principles of green analytical chemistry, providing a rapid and straightforward solution.

Synergy of iron-natural phenolic microparticles and hydrophobic ionic liquid for enrichment of tetracycline residues in honey prior to HPLC-UV detection

Iron-natural phenolic microparticles were developed as absorbents for dispersive micro solid phase extraction (D-μSPE) synergistic with hydrophobic ionic liquid (IL) for dispersive liquid–liquid microextraction (DLLME) to enrich tetracycline residues, including tetracycline, doxycycline, oxytetracycline and chlortetracycline. In situ iron microparticles synthesized from betel nut natural reagent were employed as an adsorbent for D-μSPE. The hydrophobic IL [Hmim][PF6] was synergistically utilized as an extraction solvent to extract and accumulate adsorbents bound with tetracyclines before quantitation by HPLC-UV. The synergistic combination of DLLME with D-μSPE provided excellent extraction recovery compared with individual extraction. The developed method was successfully applied to enrich and determine tetracycline residues in honey samples, with recoveries ranging from 80.0 to 121.5% and providing high enrichment factors ranging from 61 to 197. This alternative method is simple and rapid, with high extraction efficiency and a high enrichment factor and is also environmentally friendly for the analysis of tetracyclines.

Simple Microfluidic Paper-Based Analytical Device (μ-PAD) Coupled with Smartphone for Mn(II) Detection Using Tannin as a Green Reagent

The development of a simple yet greener microfluidic paper-based analytical device (μ-PAD) for on-site detection of Mn(II) in various types of waters using tannin as a natural reagent was described. The μ-PAD consists of twelve detection zones, created on a Whatman Number 1 filter paper by a simple drawing technique using an acrylic watercolor. The detection of Mn(II) was based on the color change on the reaction zone due to the reaction between Mn(II) and the pre-deposited tannin. The μ-PAD image was captured by a portable smartphone detector, and the blue intensity was digitized using a color picker application to generate the reflectance as the analytical response. The proposed method was characterized by a linear dynamic range of 0.05–0.25 mg L−1 with the limit of detection (LOD) for the determination of Mn(II) of 0.026 mg L−1. The other analytical merits of the proposed method, such as precision (RSD, 1.107%), accuracy (E, 6.697%), and recovery (104–112%), were all comparable to the existing spectrophotometric methods. The method’s successful application to natural water samples from manganese mining sites aligns with the reference spectrophotometric method, indicating its good selectivity and accuracy without significant influence of commonly associated interfering ions.

An Environmentally Friendly Compact Microfluidic Hydrodynamic Sequential Injection System Using Curcuma putii Maknoi & Jenjitt. Extract as a Natural Reagent for Colorimetric Determination of Total Iron in Water Samples.

The miniaturization of analytical systems and the utilization of nontoxic natural extract from plants play significant roles for green analytical chemistry methodology. In this work, the microfluidic hydrodynamic sequential injection (HSI) with the LED-phototransistor colorimetric detection system has been proposed to create an ecofriendly and low-cost miniaturized analytical system for online determination of iron in water samples using Curcuma putii Maknoi & Jenjitt. extracts as high stability and good selectivity of a natural reagent. The proposed method was designed for online solution mixing and colorimetric detection on a microfluidic platform. The Curcuma putii Maknoi & Jenjitt. extracts and standard/samples were sequentially aspirated to fill the channel before entering the built-in flow cell. The intensity of iron-Curcuma putii Maknoi & Jenjitt. extract complex was monitored under the optimum conditions of flow rate, sample volume, mixing zone length, and aspiration sequences, by altering the gain control of the colorimetric detector to achieve good sensitivity. The results demonstrated a good performance of the green analytical systems. A linear calibration graph in the range of 0.5-6.0 mg L-1 was obtained with a limit of detection at an adequate level of 0.11 mg L-1 for water samples with a sample throughput of 30 h-1. The precise and accurate measurement results were achieved with relative standard deviations in the range of 1.61-1.72%, and percent recoveries were found in the range of 90.6-113.4. The proposed method offers cost-effective, easy operation over an appropriate analysis time (2 min/injection) with good sensitivity and is environmentally friendly with low consumption of solutions and the use of high stability and good selectivity of nontoxic reagents. The achieved method was demonstrated to be a good choice for routine analysis.

Determination of Total Ammonia Nitrogen by Gas-Diffusion Flow Injection Analysis (GD-FIA)-Spectrophotometry using Minnieroot Flower (Ruellia tuberosa) as Natural Reagent

Total ammonia nitrogen (TAN) is a pollutant agent found in water and generated from the metabolisms of living organisms and the decomposition of organic matter. This research aims to develop an efficient, low-cost, and environmentally friendly TAN analysis method. The principle of this method is based on the reaction of TAN injected in the donor stream with NaOH to form alkaline gaseous ammonia. The gaseous ammonia diffuses through a hydrophobic membrane into an acceptor stream containing Ruellia tuberosa extract. The presence of NH3 gas in the acceptor stream changes the extract color from pinkish to green, which is monitored by spectrophotometer at 620 nm. This method was also validated based on linearity, selectivity, and accuracy. Under the obtained optimum conditions of 1 M NaOH, 5% extract, a 120 cm mixing coil, and a 200 µL sample volume, the proposed method showed excellent linearity at 10–1000 ppm (R2 = 0.993). The selectivity test result shows that this method was selective against sulfite and nitrite compounds up to 600 ppm with a % error value <10%. This method was applied to measure the total ammonia concentration in agricultural water, and satisfying results were shown by high recoveries of 95.03%–98.84%.

Can guava (Psidium guajava) leaf extracts develop an indigenous, simplified tool for a semi-quantitative assessment of iron in groundwater?

Iron present in the drinking groundwater is attributed to the low burden of iron deficiency (ID) in Bangladesh. The supplemental anemia prevention strategies involving iron need a cautious approach due to the excess load of iron and the side effects. The present pilot study examined the potential of the guava leaf extracts to use as a natural reagent for the assessment of iron in groundwater. Eighteen households with the drinking source of groundwater were randomly selected. Guava leaves were crushed and the shreds of the leaves were mixed with the water sample. Changes of water color were photographed. Five groups were identified - 'whitish', 'shades of pink', 'shades of purple', 'light black' and the 'frank black'. The iron concentration was measured by a test kit device. Each color group was assigned a number on the ordinal scale 1-5. Statistical correlation and agreements were performed between the methods. The positive correlation (Kendall's tau b: 0.89, p < 0.000) and the agreements (Kappa: 0.77, p < 0.000; rho_c: 0.73, p < 0.000) were observed. Guava leaf extracts may standardize an indigenous tool for a semi-quantitative measurement of groundwater iron content. Validation of the tool thus may aid in the design and evaluation of the iron supplementation and fortification programs.

Application of an Economic USB Digital Microscope for Microvolume Colorimetric Determination of Iron in Supplements with a Guava Leaf Extract

The method for iron determination by using the microvolume of chemicals coupled with employing natural reagent was proposed towards green analytical chemistry. A simple, portable, and economic digital microscope was used to magnify the drop of 30 μL of product, that was mixed between sample and guava leaf extract reagent, to monitor the analytical signal as primitive color, red/ green/blue or RGB. The optimum conditions for the reagent extraction and the RGB detection were investigated. The calibration graph with linearity in the range of 40-120 mg L-1 Fe(III) was obtained with the detection limit at 10.8 mg L-1. High precision was achieved with %RSD less than 1.8%. The developed method was successfully applied to the assay of iron in supplement samples and found to be in good agreement with the results obtained by the FAAS method at the 95% confidence level.

The effect of Ganoderic Acid A on miR-17-5p and miR-181b expression level and apoptosis induction in human leukemia Nalm-6 cells

Background: In various cancers, Ganoderic Acid A (GAA), an active triterpenoid derived from Ganoderma lucidum, has been proved to show potent anti-tumor effects. However, the possible impacts of GAA on the human leukemia cell line (Nalm-6) are not fully elucidated. Therefore, this research aimed to study the antineoplastic effect of GAA on Nalm-6 cells.&#x0D; Materials and Methods: In this laboratory trial study, Nalm6 cells were cultured in vitro and treated with different doses of GAA (25, 50, 100, 200, and 400 μg/mL) for 24, 48, and 72 hours. The optimal treatment concentration of GAA was determined by the MTT assay. Flow cytometry was used to determine the death of Nalm-6 cells caused by GAA treatment by utilizing FITC-conjugated propidium iodide (PI) and annexin V staining. After incubation, the expression levels of miR-17-5p and miR-181b were monitored using real-time polymerase chain reaction (PCR).&#x0D; Results: Based on the half-maximal inhibitory concentration (IC50) measurements of the MTT assay, the optimal treatment concentration of GAA was 140 μg/mL (in a dose and time-dependent manner, p&lt;0.0001). The GAA treatment was selectively toxic to the leukemia Nalm-6 cells and could remarkably induce cell apoptosis (p&lt;0.0001). Besides, GAA downregulated the expression of miR-17-5p and miR-181b in the Nalm-6 cells compared with the untreated cells (P=0.0067 and P=0.0014, respectively).&#x0D; Conclusions: Based on the present findings, GAA merits further investigation as a promising natural reagent for treating hematologic malignancies.

Green Analytical Approach for the Determination of Zinc in Pharmaceutical Product Using Natural Reagent.

A selective, sensitive, and environmentally safe spectrophotometry method was developed and validated for the determination of zinc in pharmaceutical substances using natural reagents obtained from the leaves of plant Acacia catechu. Different factors were optimized such as volume of reagent, selection of pH, and stability of the color complex. The drug showed a stable yellowish orange color complex at 550 nm. The greenness of the methods was estimated using an eco-scale tool where the presented method was found to be excellent green with an ecoscore of 84 based on spectrophotometric determination. Also, the greenness of the method was assessed by the Green Analytical Procedure Index and found to be eco-friendly. The method was validated in conformance with ICH guidelines, with acceptable values for linearity, accuracy, precision, LOD, and LOQ. The linearity range for zinc sulphate was 5–25 μg mL−1 with an R2 value of 0.996. The % RSD for intraday precision and interday precision was less than 2%. The suggested method can be employed for the economic analysis of zinc in its pure form and various formulations. The presented spectrophotometric method is the first analytical method for the analysis of zinc present in zinc sulphate and showed greater ecoscale as compared to the official method.

Magnetically recyclable ZnCo2O4/Co3O4 nano-photocatalyst: Green combustion preparation, characterization and its application for enhanced degradation of contaminated water under sunlight

Finding the appropriate photocatalyst for elimination of organic contaminants is a challenge for remediation of environment. Herein, we tried to synthesis of ZnCo2O4/Co3O4 nanocomposite using the Stevia extract as a natural reagent that can act as green fuel in auto-combustion sol-gel method and control the size of product by steric-hindrance induced by its structure. The chelating role of this natural reagent was investigated by changing the amount of this extract for synthesis of different samples. Analyses confirmed the effect of this parameter on morphology and size of products. The photocatalytic activities of different samples under visible irradiation were investigated and the effect of size of photocatalyst on degradation percent of dye was studied. The good performance of ZnCo2O4/Co3O4 nanocomposite was detected by degradation of Acid violet 7 about 93.5% in 70 min and 2-phenol about 100% in 18 min. Photocatalyst was easily recycled through magnetic properties of products and stability of it under irradiation was confirmed by degradation of dye after 10 times recycling.

Green synthesis of DyBa2Fe3O7.988/DyFeO3 nanocomposites using almond extract with dual eco-friendly applications: Photocatalytic and antibacterial activities

For the first time, photocatalytical and antibacterial activities of DyBa 2 Fe 3 O 7.988 /DyFeO 3 (Dy-Ba-Fe-O) nanocomposites as eco-friendly applications of this compound was studied in the same time. Since the applications of this compound are eco-friendly, ultrasound technique was chosen as the synthesis method. Achieving the pure product with good crystallinity with the lowest energy consumption can be considered as one of the advantages of this work. Using the almond core extract as a natural reagent was another reason for consideration this method as a green process. Band gap of this nanocomposite was estimated about 2.6 eV that showed this product can be used as a visible-active photocatalyst. Rhodamin-B dye as an organic pollutant model using the as-prepared nanocomposite was degraded about 72% that was a considerable result under visible irradiation. Elimination of microorganisms was studied by disc diffusion to recognize the sensitivity of bacterial ( Staphylococcus aureus , Bacillus subtilis, E. coli , K. pneumonia and P. aeruginosa ) strains the manufactured. The results confirmed that DyBa 2 Fe 3 O 7.988 /DyFeO 3 (DBFeO) nanocomposites can be used as an antibacterial agent because of the manifested strong antibacterial ability upon Gram-negative pathogens such as K. pneumonia and E. coli . The properties of this product were characterized by different analyses including SEM, XRD, EDS, FT-IR, DRS and TEM. • DyBa 2 Fe 3 O 7.988 /DyFeO 3 nanocomposites were created via ultrasound aided green synthesis. • Gram-negative bacteria exhibit more responsiveness to NCS than behave Gram-positive bacteria. • Uniformity of nanocomposites measurement and form can affect their antibacterial activity. • The created Dy-Ba-Fe-O NCs displayed antibacterial ability. • Dy-Ba-Fe-O nanocomposite has been utilized for photodegradation of dyes.

An application study of membraneless-gas separation microfluidic paper-based analytical device for monitoring total ammonia in fish pond water using natural reagent.

The membraneless-gas separation microfluidic paper-based analytical device(ML-GSμPAD), consisting of donor, spacer, and acceptor layers, was developed to monitor total ammonia in fish pond water. The principle of the analysis involved the addition of sodium hydroxide solution to the sample zone in the donor layer containing ammonia/ammonium, and the produced ammonia gas diffuses through the spacer to the detection zone in the acceptor layer containing red rose extract to produce a color change from pink to blue corresponding to the ammonia/ammonium concentration. Under optimum conditions, the proposed method provided good linearity of ammonia in the range concentration of 0-100mg L-1 (R2 = 0.9993) with LOD and LOQ of 2.25 and 7.51mg L-1, respectively. This method was successfully applied to fish pond water samples without significant influence of interfering compounds with recoveries in the range of 103-110%, indicating good selectivity and accuracy of the proposed method.

Experimental study and recognition of natural gas hydrate chemical reagent - CO2 exploitation

Abstract In order to solve the problems of slow replacement rate and low degree of substitution in the process of CO2 displacement by natural gas hydrate, a method of chemical reagent-CO2 displacement combined mining experiment was proposed. Taking the thermodynamic methanol inhibitor as an example, three groups of experiments were carried out: critical temperature pressure condition for CH4 decomposition at different methanol concentrations, CH4 hydrate decomposition under the condition of methanol reagent at 30% concentration, and methanol reagent-CO2 combined mining. Experiments show that: (1) The concentration of methanol plays a decisive role in hydrate recovery. Methanol reagent has the property of highly reducing the formation temperature of hydrate. Methanol solution concentration is positively correlated with the critical temperature drop of hydrate decomposition and formation pressure. (2) The methanol solution decomposition of hydrate can be roughly divided into three stages: the initial stage of rapid decomposition, the competitive stage of hydrate decomposition and stable transformation, and the stable stage of decomposition. Through experimental simulation, it is concluded that formation pressure is a direct factor affecting the decomposition ability of methanol reagent to hydrate. By changing formation pressure, the rate of CH4 hydrate recovery can be improved. (3) A higher hydrate decomposition rate can be obtained based on the methanol reagent-CO2 displacement mining method. In the action of the methanol reagent, the subsequent injection of CO2 still promotes the decomposition of CH4, that is, the displacement of CO2 hydrate after the decomposition of the hydrate based on the methanol reagent is feasible. The research results are of great significance especially for large-scale mine test mining of permafrost natural gas hydrate chemical reagent method.

Smartphone-based digital image colorimetry for determination of iron in cereals and crispy seaweed using Terminalia chebula retz. extract as a natural reagent.

In this research, a novel sample pretreatment of whole wheat bread, granola, and crispy seaweed samples was developed for iron(III) determination by digital image colorimetry. The developed method was compared with UV-visible spectrophotometry. The procedure involved weighing the sample (∼0.1 g) and mixing it with a mixture of concentrated nitric acid (65%) and hydrogen peroxide (30%) (2 : 1 v/v). Then, the mixture was irradiated with UV light until it became dry. The residue was then dissolved in deionized water. The sample solution was diluted with deionized water before forming a complex with Terminalia chebula Retz. extract in acetate buffer. Under the optimal conditions, the color of the complexes was violet. When analyzed with an inhouse developed smartphone-based digital image colorimeter, the linear range was 1.0-6.0 mg L-1 with a correlation coefficient of >0.993. The percentage recoveries were in the range of 84.8-90.2. The limit of detection (LOD) and the limit of quantification (LOQ) were 1.06 and 3.55 mg L-1, respectively. From the results, it can be concluded that the developed method is accurate, simple, cost-effective, and environmentally friendly. The statistical paired t-test proved that there was no significant difference in the results when compared with a UV-visible microplate reader using gallic acid as the color forming reagent and a flame atomic absorption spectrophotometer as a reference instrument at 95% confidence level.

Dual determination of nitrite and iron by a single greener sequential injection spectrophotometric system employing a simple single aqueous extract from Areca catechu Linn. serving as a natural reagent.

Dual determination of nitrite and iron was proposed by using a single greener sequential injection (SI) spectrophotometric system employing a simple single aqueous extract from Areca catechu Linn. The extract served as a natural reagent to replace N-(1-naphthyl)ethylenediamine (NED) of the Griess reagent with nitrite and 1,10-phenanthroline with iron. The color products possessed analytical wavelengths at 430 and 560 nm, respectively. Conditions for the SI procedure were optimized using a univariate experimental design. Calibration ranges were up to 5.0 mg L−1 and 10.0 mg L−1 with limits of detection (LODs) of 0.04 mg L−1 and 0.05 mg L−1 for nitrite and iron(iii), respectively, and relative standard deviations (RSDs) being less than 3%. Recoveries of spiked standard nitrite and iron(iii) at 0.3 mg L−1 and 0.5 mg L−1 in water samples were 88 to 104% and 84 to 109%, respectively. The developed method successfully achieved dual determination of nitrite and total iron agreeing at a 95% confidence level with the reference methods of the conventional Griess assay and flame atomic absorption spectrometry (FAAS), respectively. The proposed method utilized locally available material from plants and serves the UN-SDGs.

Sustainable Education with Local-Wisdom Based Natural Reagent for Green Chemical Analysis with a Smart Device: Experiences in Thailand

To minimize chemical waste and protect the environment, our team has used green analysis with natural reagents. In this work, we designed a natural-reagent assay kit for iron determination and implemented it in chemistry education in Thailand. The iron assay method was adapted from Thai local wisdom of testing water quality using guava leaves. The guava leaf powder served as a natural reagent in the assay. The kit included equipment, standard and buffer solutions and a manual. A smart device with a built-in camera was used as a detector. Educators in six universities in Thailand implemented the kit in laboratories with modifications depending on their learning outcomes. The kit implementation was evaluated using a survey with questions in four aspects: usability, learning achievement, green chemistry and portability. The high average scores for all questions (&gt; 4.00 of 5.00 points), with the average overall score of 4.53 ± 0.60, indicated satisfaction regarding in all aspects. Using a locally available bio-resource as a natural reagent for green analysis in chemistry education supported sustainable education in Thailand, in terms of quality education (SDG 4) and reduced inequalities (SDG 10) and environmental sustainability (SDG 6—Clean water and sanitation, 12—Responsible consumption and production and 14—Life be-low water).

Exploiting crude betel nut (Areca catechu Linn.) extracted solution as a natural reagent with sequential injection spectrophotometry for iron analysis in rice samples

Exploiting crude betel nut (Areca catechu Linn.) extracted solution as a natural reagent with sequential injection spectrophotometry for iron analysis in rice samples

An Environmentally Friendly Flow Injection-Gas Diffusion System Using Roselle (Hibiscus sabdariffa L.) Extract as Natural Reagent for the Photometric Determination of Sulfite in Wines.

In this work, a green and simpler method for photometric determination of sulfite based on a flow injection-gas diffusion (FI-GD) system using a natural reagent extracted from roselle (Hibiscus sabdariffa L.) was proposed. Despite the fact that the employed reaction is not selective to sulfite, its sensitivity is high, and the selectivity can be improved by coupling a GD unit to the FI system. The method involves monitoring a decrease in absorbance of the reagent solution that is used as an acceptor solution. When a standard solution or sample solution was injected into an acidic donor stream, the liberated sulfur dioxide diffuses through a gas-permeable membrane of the GD unit into the acceptor solution, causing color fading of the reagent. A linear analytical curve in the range of 5–100 mg L−1 was obtained with a detection limit of 2 mg·L−1. Relative standard deviations of 0.9%, 0.6%, and 0.6% were obtained for the determination of 30, 70, and 100 mg·L−1 SO32- (n = 11). The developed method was applied to wine samples, giving results that agreed with those obtained with the Ripper titrimetric method. The proposed method offers advantages of simplicity, cost-effectiveness, and being environmentally friendly such as reduced chemical consumption and less waste generation.

Kinetics of Carbon Dioxide Removal Using N-Acetylglucosamine.

Glucosamine, the amino sugar made from glucose, is a safe and natural reagent for post-combustion carbon dioxide capture. Its most plentiful derivative, N-acetylglucosamine (or NAG), was studied in this work with respect to its reaction kinetics in aqueous solutions. A stirred cell reactor with a flat gas–liquid interface was used, and it was found that CO2 reacts with NAG via a pathway similar to that with alkanolamines. In the 20–100 mM range of NAG concentration, the second-order rate constant at T = 308 K was 125 kmol m–3 s–1. For the 303–313 K range, the activation energy was 42 kJ mol–1. In a study on vapor–liquid equilibrium, it was found that the loading capacity of NAG (100 mM) at 303 K was 0.6 mol CO2/mol NAG, while the equilibrium partial pressure of CO2 was 0.8 kPa. Three rate promoters were tested, and piperazine showed better efficacy than monoethanolamine and 2-amino-2-methyl-1-propanol in aqueous NAG solutions. This work is expected to stimulate further interest in this new, green CO2 capturing solvent.