UV-Vis Spectrophotometric Determination Research Articles

Detecting dissolved mercury(ii) ions using chitosan-AgNP strips integrated with smartphones.

A simple preparation of a paper strip test with a smartphone-based instrument for detecting dissolved mercury is still in development. This study aims to develop a smartphone-based colorimetric paper strip test using chitosan-stabilized silver nanoparticles for detecting dissolved mercury. The method demonstrated high sensitivity and selectivity for Hg2+ ions, with detection limits comparable to UV-vis spectrophotometry. Silver ions embedded in the chitosan matrix were reduced by either sodium NaBH4 or N2H4. Both chi-AgNP colloidal and chi-AgNP paper strips were tested for sensitivity of mercury(ii) solution detection with and without ion interference. The accuracy of colour change responding to the mercury concentration was recorded with several smartphones in a handmade cubical and a T-shape micro-studio. Only NaBH4 gives colloidal chi-AgNPs relatively dispersed, and the colloidal chi-AgNPs become aggregated when AgNP interacts with mercury(ii) ions. The colour change of chi-AgNP paper strips responding to the concentration of mercury(ii) and quantified using a smartphone is consistent when confirmed with UV-vis spectrophotometric determination with a comparable limit of detection (0.76 μM). The inferring ions do not significantly affect mercury(ii) analyses. Therefore, the paper strip integrated with the smartphone is effectively used for mercury(ii) detection in water as long as the mercury concentration is >1 μM. This finding might inspire advanced technology with a larger number of data references, and machine learning involvement to develop more compatible and simple mercury detection.

Simultaneous UV-Visible Spectrophotometric Determination of Nelfinavir and Quercetin in Patented Pharmaceutical Formulation and Bulk by First-Order Derivative Spectroscopic Method

Simultaneous UV-Visible Spectrophotometric Determination of Nelfinavir and Quercetin in Patented Pharmaceutical Formulation and Bulk by First-Order Derivative Spectroscopic Method

UV-Vis spectrophotometric determination of rare earth elements (REE) speciation at near-neutral to alkaline pH. Part I: m-cresol purple properties from 25-75 °C and Er hydrolysis.

The speciation and mobility of rare earth elements (REE) strongly depends on pH, which controls the formation of charged aqueous hydroxyl species. The latter potentially play an important role in controlling heavy REE adsorption on clay minerals in near-neutral to alkaline waters such as in regolith-hosted REE mineral deposits. However, accurate REE hydrolysis constants are needed for developing geochemical models that can predict the role of these charged species in natural systems. Here, we develop a robust experimental UV-Vis spectrophotometric method using m-cresol purple to determine in situ pH from 25 to 75 °C. This method is used to derive the average ligand number and hydrolysis constants of erbium (Er) at 25 °C in aqueous solutions with low ionic strength (≤0.001 mol L-1) at pH from ∼7 to 9.5 and in the presence of Er concentrations from 0 to 0.057 mM. The average ligand number ranges between 1 and 3 indicating that Er(OH)2+, Er(OH)2+ and Er(OH)03 control speciation in the experiments. The logarithm of the Er hydrolysis constants (, n = 1 to 3) derived at infinite dilution for the reaction Er3+ + nH2O = Er(OH)n3-n + nH+ are: , , . Implementation of these experimental data into a geochemical model indicates that the Er(OH)2+ and Er(OH)03 species are both stable in a much wider pH range than previously predicted. Consequently, the positively charged REE hydroxyl complexes can potentially control the fractionation of light vs. heavy REE via adsorption as observed in the formation of certain regolith-hosted REE deposits.

Selective separation and determination strategy for monitoring E100, E127, E129 and E133 in foodstuffs: Vortex assisted sequential-simultaneous liquid phase micro-extraction

A green, speedy and handy, vortex assisted sequential-simultaneous liquid phase micro-extraction procedure (VA-SS-LPME) was established first time without using any instrumental chromatographic techniques for separation, preconcentration and spectrophotometric determination of four important popularly and widely used food colorants, namely curcumin (E100), erythrosine (E127), allura red (E129) and brilliant blue (E133). Here, n-nonanol and n-nonanol based deep eutectic solvent were used as extraction solvents. The procedure has included two simultaneous and sequential separation steps by different extractants and two simultaneous UV–vis spectrophotometric determination steps. First, simultaneous separation of E100 and E127 from aqueous solution containing E129 and E133 was achieved and then simultaneous separation of E129 and E133 from aqueous solutions was applied and simultaneous spectrophotometric determinations were performed finally for binary mixture dyes (E100 and E127) and (E129 and E133). The parameters including pH, types and amounts of extractants, vortex time and rate, centrifugation time and rate were investigated in detail for sequential two steps separation and quantitative simultaneous extraction of the dyes. Interference effect of matrix ions, target and other dyes were examined. Possible envisaged extraction mechanisms were elucidated. Green analytical procedure index (GAPI) and analytical eco-scale (AES) parameters of the procedure were determined. As last, E100, E127, E129 and E133 contents of some foodstuffs and pharmaceuticals such as confectioneries, beverages, drugs and syrups were determined by applying optimized procedure. Colourful food additive concentrations of real samples were determined between 2.9 and 93.8 µg/g and 5.3–112.4 µg/mL for solid and liquid samples, respectively.

Comparative Studies on Spectrophotometric Determination of Selected Heavy Metals in Environmental and Biological Samples with Synthetic Phenylhydrazones as Chromogenic Reagents

This work involves a comparative study on a simple, sensitive, selective and non-extractive Uv- Vis spectrophotometric method for the determination of cadmium, lead, chromium and arsenic in biological, soil and water samples using synthesized and characterized phenylhydrazones; [glutaraldehyde phenylhydrazone (GPH) and acetylpyridine-2,4-dinitrophenylhydrazone (APDH)] as the chromogenic reagents was developed. GPH and APDH were synthesized as new chromogenic analytical reagents for the direct UV-Vis spectrophotometric determination of the selected metals of interest in a slightly acidic pH of 6.5-7.5 and 20% dimethylformamide (DMF) solution to give stable coloured metal-ligand complexes. The reactions were instantaneous; the wavelengths of maximum absorptions were followed spctrophometrically and noted. The analytical properties of the reagent APGH on the metals (Cd, As, Pb, and Cr) revealed the wavelength of maximum absorption ranged between 385.0 (Cr) to 440.0nm for (Pb). The reagent APDH had molar absorptivities (L mol -1 cm -1 ) ranging from 2.006 x 10 4 (Pb) to 2.407 x 10 4 (Cd), a mole ratio of metal to ligand of 1:1, a detection limit (µg/g) ranging from 0.3272 (As) to 0.4456 (Cd) and the metal-ligand complex was stable for 0-36 hours. The reagent GPH revealed a wavelength of maximum absorption between 360.0 (Cr) to 395.0 nm for (Pb and As) at a working pH of 6.5 to 7.5 room temperature (37°C). The reagent GPH had a molar absorptivities (L mol -1 cm -1 ) ranging from 2.213 x 10 4 (Pb) to 2.460 x 10 4 (As), a mole ratio of metal to ligand of 2:1, the detection limit (µg/g) ranging from 0.3432 (As) to 0.5250 (Pb) and the metal-ligand complex was stable for 0-48 hours. Both reagents had a Beer’s law validity range (mgL -1 ) of 0.001 to 100. The Sandell’s sensitivities (µg/cm 2 ) ranged from 0000409 (As) to 0.00499 (Pb) for APDH and 0.00406 (As) to 0.00452 (Pb) respectively. Large excess of cations and anions as possible interferences up to 1

In-vivo exposure of a plant model organism for the assessment of the ability of PM samples to induce oxidative stress

This study aims to propose an innovative, simple, rapid, and cost-effective method to study oxidative stress induced by PM through in-vivo exposure of the plant model organism Arabidopsis thaliana. A. thaliana seedlings were exposed to urban dust certified for its elemental content and to PM2.5 samples collected in an urban-industrial area of Northern Italy. An innovative technique for the detachment and suspension in water of the whole intact dust from membrane filters was applied to expose the model organism to both the soluble and insoluble fractions of PM2.5, which were analyzed for 34 elements by ICP-MS. Oxidative stress induced by PM on A. thaliana was assessed by light microscopic localization and UV–Vis spectrophotometric determination of superoxide anion (O2−) content on the exposed seedlings by using the nitro blue tetrazole (NBT) assay. The results showed a good efficiency and sensitivity of the method for PM mass concentrations >20 μg m−3 and an increase in O2− content in all exposed seedlings, which mainly depends on the concentration, chemical composition, and sources of the PM administered to the model organism. Particles released by biomass burning appeared to contribute more to the overall toxicity of PM. This method was found to be cost-effective and easy to apply to PM collected on membrane filters in intensive monitoring campaigns in order to obtain valuable information on the ability of PM to generate oxidative stress in living organisms.

UV-Vis spectrophotometric determination of isoprene in atmosphere based on Diels–Alder reaction

ABSTRACT Isoprene is the most abundant biogenic volatile organic compound in the atmosphere. Till now, chromatography is the main detection method for isoprene, dependent on sophisticated instruments and complex operations. An UV-Vis spectrophotometric method based on the Diels–Alder (D-A) reaction was developed to detect isoprene in the atmosphere. The fast D-A reaction between the probe 4-phenyl−1,2,4-triazolin−3,5-dione (PTAD) and isoprene may cause absorbance decrease, which enable it to detect isoprene in solution at 118 nmol·L−1 level. Further, isoprene in air at the level of ppbv was detected using this method. Compared with chromatography this method has the advantages of low cost, fast and less dependence on instrument.

UV-Visible Spectrophotometric Determination of Formalin Contamination in Tofu Circulated in Maros City - Indonesia

Tofu is one of the healthiest foods because of its high protein content and the quality is equivalent to the quality of animal protein. Formaldehyde has a function as an antibacterial agent that can slow down the activity of bacteria in foods that contain a lot of protein, so formaldehyde reacts with proteins in food and makes food durable, but when it enters the human body, formaldehyde itself is mutagenic and carcinogenic which can trigger the growth of cancer cells. and gene defects in the body. Thus, in this study, we aim to determine the formalin contamination in tofu circulated in Maros City – Indonesia. This research was conducted from December 2014 to June 2015. The analysis of formalin contamination in tofu was conducted in qualitative and quantitative analysis. The qualitative analysis was performed using the specific reagent, and the quantitative analysis was measured by UV-Vis spectrophotometric method. The result showed that sample codes RMD1 and RMD2 with formalin contaminants because the color of the solution produced after the test was red correspond to the positive result. As for the tofu sample with sample code RMD3, the results were negative because it gave a yellow color after adding potassium permanganate reagent. In the quantitative analysis, samples were measured using a UV-Vis spectrophotometer at a wavelength of 571.5 nm. From the measurement process, the result exhibited that the samples RMD1 and RMD2 contain formalin of 5.92 and 3.34 g/gram, respectively.

Synthesis of new Zn-decorated metal-organic frameworks for enhanced removal of carcinogenic textile dye: equilibrium and kinetic modeling studies

This paper describes the synthesis and characterization of Zn2+ decorated (adipic and terephthalic acid as linkers) piperazine-based metal-organic framework (P-MOFs) and their extraction behavior toward the Chicago sky blue (CSB) dye. The formation of Zn2+-decorated P-MOFs was confirmed by FT-IR spectroscopy, energy-dispersive spectroscopy, X-ray diffraction, BET surface area analysis and TGA. Adsorption behavior of the synthesized P-MOFs was explored through solid-phase adsorption (batch method) prior to UV-Vis spectrophotometric determination. Adsorption parameters, including adsorbent dosage, pH of solution, dye concentration, and time, were optimized. Excellent percentage removal of 94% and 95% for AP-Zn-MOF and TP-Zn-MOF, respectively, was achieved at pH 7.5. Kinetics studies indicated that the synthesized adsorbents AP-Zn-MOF and TP-Zn-MOF followed the pseudo-second-order rate model with R 2 value 0.9989. The Freundlich isotherm with high R 2 value as compared to Langmuir isotherm indicated that CSB adsorption for the synthesized MOFs follows multilayer adsorption.

UV-Vis Spectrophotometric Determination of Selected Heavy Metals (Pb, Cr, Cd and As) in Environmental, Water and Biological Samples with Synthesized Glutaraldehyde Phenyl Hydrazone as the Chromogenic Reagent

A simple, sensitive, selective, and non-extractive UV-Vis spectrophotometric method for the determination of cadmium, lead, chromium, and arsenic in biological, soil and water samples using synthesized and characterized phenyl hydrazone; glutaraldehydephenyl hydrazone (GPH) as the chromogenic reagent was developed. GPH was synthesized as new chromogenic analytical reagents for the direct UV-Vis spectrophotometric determination of the selected metals of interest in a slightly acidic pH of 6.5-7.5 and 20 % dimethylformamide (DMF) solution to give stable coloured metal-ligand complexes. The reactions were instantaneous; the wavelengths of maximum absorptions were followed spectrophotometrically and noted. The reagent GPH revealed a wavelength of maximum absorption between 360.0 (Cr) to 395.0 nm for (Pb and As) at a working pH of 6.5 to 7.5 room temperature (37 °C). The reagent GPH had a molar absorptivity (L mol-1 cm-1) ranging from 2.213×104 (Pb) to 2.460×104 (As), a mole ratio of metal to ligand of 2:1, the detection limit (µg/g) ranging from 0.3432 (As) to 0.5250 (Pb) and the metal-ligand complex was stable for 0-48 hours. The reagents had a Beer’s law validity range (mg L-1) of 0.001 to 100. The Sandell’s sensitivities (µg/cm2) ranged from 0000409 (As) to 0.00499 (Pb) for APDH and 0.00406 (As) to 0.00452 (Pb) respectively. Large excess of cations and anions as possible interferences up to 15 folds were studied and do not interfere with the determination of the selected metals of interest. The developed method is highly selective for Cd, Pb, and Cr and As and was successfully used for the determination for the said elements in soil, water, and biological samples. The results of the developed methods were comparable with AAS and were found to be in good agreement. The method had very high precision and very good accuracy.

Depression mechanism of environment-friendly depressant dithiocarbamate chitosan in flotation separation of Cu-Zn sulfide

The depressant performance and mechanism of dithiocarbamate chitosan (DTC-CTS) in flotation separation of chalcopyrite and sphalerite were investigated by micro-flotation experiment, UV–vis (UV–vis) spectrophotometer determination, time of flight secondary ion mass spectrometry (ToF-SIMS) test and local electrochemical impedance spectroscopy test (LEIS). The flotation results of Cu-Zn (1:1) mixed sulfide showed that chalcopyrite can be effectively separated from sphalerite using DTC-CTS as depressant and butyl xanthate as collector. The optimum conditions for flotation separation of chalcopyrite from the Cu-Zn sulfide were as follows: the dosage of DTC-CTS of 0.4 mg/L, butyl xanthate of 1 × 10−5 mol/L and flotation pH of 10. Copper concentrate with Cu grade of 31.93% and recovery of 85.97%, Zn grade of 4.82% and recovery of 4.18% can be obtained under the above conditions in the Cu-Zn sulfide flotation system. The results of ToF-SIMS showed that DTC-CTS can adsorb on both chalcopyrite and Cu-activated sphalerite surfaces, and the adsorption capacity on the two surfaces is roughly equivalent. UV–vis Spectrophotometric determination and LEIS results indicated that DTC-CTS strongly blocks the subsequent collector adsorption of butyl xanthate on sphalerite surface, but has little effect on the adsorption of butyl xanthate on chalcopyrite. Such difference of collector adsorption on chalcopyrite and sphalerite surfaces differs the surface hydrophobic and further results in the selective separation of chalcopyrite from Cu-Zn sulfide ore.

Application of microextraction techniques for indirect spectrophotometric determination of fluorides in river waters

The present study is dedicated to development of improved method for determination of trace amounts of fluorides in natural waters which is based on the interaction of fluorides with ion associate (IA) of Al(III), salicylic aldehyde acylhydrazones (benzhydrazone (SABH) and 4-picolinhydrazone (SAPH)) and polymethine dye Astra Phloxine FF (AP). Comparison of analytical forms [Al(SABH)2]⋅AP and [Al(SAPH)2]⋅AP showed that the analytical system Al(III)-SAPH-AP is more effective, namely, a higher level of preconcentration of the analytical form is ensured by and extraction equilibrium is achieved faster. Based on the study, we propose a new, fast, simple, reliable, sensitive, and accurate method of the indirect UV–Vis-spectrophotometric determination of fluorides grounded on the interaction of fluorides with IA of Al(III), SAPH and AP with the utilization of vortex-assisted liquid-liquid microextraction (VALLME). The method is based on the discoloration of the microextract of IA of Al(III), SAPH and AP (Al-SAPH-AP) in presence of fluoride ions due to the formation of fluoride complexes of aluminum with higher stability. The effect of various factors has been studied. The optimal conditions of the UV–Vis-spectrophotometric determination of fluorides were defined as: pH 7.0–10.0, 1.0⋅10−6 mol⋅L−1 Al(III); 4.0⋅10−5 mol⋅L−1 SAPH; 1.0⋅10−6 mol⋅L−1 AP; λ = 560 nm. VALLME have been carried out in 250 μL of CCl4 at 20:1 vol ratios of aqueous and organic phases, with vortexing at 3000 rpm for 15 s followed by centrifugation at 2000 rpm for 2 min. The determination of fluorides is feasible in the presence of various interferences. The calibration curve shows the linear dependence in the range of 0.3–114 μg⋅L−1 of the fluorides concentration (R2 = 0.993) with the limit of detection of 0.086 μg⋅L−1 and the limit of determination of 0.284 μg⋅L−1. The accuracy of the proposed protocol of fluorides determination was verified towards a reference method on the samples of natural rivers waters (RSD 2.6–3.1%, recovery 98.3–101.4%).

UV-VIS spectrophotometric determination of magnesium after complexing with 8-hydroxy quinoline in sodium dodecyl sulphate micellar medium

In this study, an alternatifive UV-VIS spectrophotometric method for determination of magnesium was proposed. The method is based on complexation with 8-hydoxyquinoline (oxin) in sodium dodecyl sulphate (SDS) micelle medium, the absorbance of the product was recorded at 390 nm. pH of the solution, the concentration of ligand and surfactant were critical parameters, which affect the absorbance measurements, and optimised. The molar absorptivitiy coefficient is 5×102 Lmol-1cm-1, the Sandell’s sensitivity is 0,052 µgcm-2, detection limit is 0,3 mgL-1, quantification limit is 1,1 mgL-1 and linear working range is 2-8 mgL-1 at pH 12 and 390 nm. The proposed method was applied for determination of magnesium to some drug and mineral water samples, nearly good accuracy and reproducible volues were obtained percent as recovery and relative standart deviation.

A new strategy for the combination of supramolecular liquid phase microextraction and UV–Vis spectrophotometric determination for traces of maneb in food and water samples

A novel and green method was developed for enrichment of maneb (manganese ethylene-bisdithiocarbamate) with a supramolecular solvent liquid phase microextraction method. The microextraction method has been used for the first time in the literature for separation-preconcentration of maneb. 1-decanol and tetrahydrofuran were used in the supramolecular solvent formation. The Mn2+ content of maneb was extracted in the supramolecular solvent phase as 1-(2-pyridylazo)-2-naphthol complex at pH 12.0. Manganese concentration was determined by UV–Vis spectrophotometer at 555 nm. Then, the maneb concentration equivalent to manganese concentration was calculated. The analytical parameters which effective in the method, including pH, volume of reagents, and sample volume were optimized. The limit of detection and the limit of quantification values for maneb were calculated as 2.22 μg L−1 and 7.32 μg L−1, respectively. The method was successfully applied in the analysis of the maneb content of water and food samples.

Simple and Rapid Method by Sensitive Value of UV-Visible Spectrophotometric Determination of Copper (II) by Cloud Point Extraction

Simple and Rapid Method by Sensitive Value of UV-Visible Spectrophotometric Determination of Copper (II) by Cloud Point Extraction

A green and simple liquid-phase microextraction based on deep eutectic solvent for the erythrosine prior to its UV–VIS spectrophotometric detection

A simple, sensitive, effective and rapid liquid-phase microextraction (LPME) method based on deep eutectic solvent (DES) was developed for the preconcentration and determination of erythrosine in the drug, water and powdered fruit juice samples prior to its UV–VIS spectrophotometric determination. In the DES-LPME study, the analytical parameters affected on extraction efficiency of the analyte were optimized. Under the optimum experimental conditions, the limits of detection and limit of quantification were obtained as 0.53 µg L−1 and 1.78 µg L−1, respectively. The preconcentration factor was calculated as 100. Accuracy of the proposed microextraction method has been checked by analyzing the addition–recovery studies to in real samples and satisfactory results were obtained.

Aktivitas Antioksidan dan Potensi Tabir Surya Serum Ekstrak Terpurifikasi Daun Wangon (Olax psittacorum (Willd.) Vahl.)

Perkembangan sediaan kosmetika herbal saat ini semakin pesat. Salah satunya adalah serum yang disukai masyarakat karena lebih nyaman digunakan dan lebih mudah menyebar di permukaan kulit. Pada umumnya serum mengandung senyawa antioksidan yang poten sebagai anti aging di mana formulanya dikaitkan dengan komponen antioksidan di dalamnya. Ekstrak etanol daun wangon telah diteliti mengandung senyawa golongan flavonoid yang mempunyai potensi antioksidan. Penelitian ini bertujuan untuk membuat ekstrak terpurifikasi daun wangon selanjutnya dibuat sediaan kosmetika serum yang diuji mutu fisik dan stabilitas antioksidannya serta dilakukan pengujian terkait potensinya sebagai tabir surya sehingga diharapkan dapat dilakukan inovasi terhadap sediaan serum yang dihasilkan.
 Penelitian diawali dengan pembuatan ekstrak dengan pelarut etanol 96%. Selanjutnya dilakukan fraksinasi terhadap ekstrak kasar dengan metode ekstraksi cair-cair yang berturut-turut menggunakan pelarut n-heksana dan etil asetat. Kandungan flavonoid dalam ekstrak terpurifikasi dimonitoring secara KLT. Selanjutnya dibuat formulasi sediaan serum dengan 1,1 % zat aktif ekstrak terpurifikasi daun wangon dan dilakukan uji mutu fisik terhadap sediaan tersebut meliputi organoleptis, pH, viskositas dan homogenitasnya. Selanjutnya ekstrak terpurifikasi dan sediaan serum diuji aktivitas antioksidannya dengan metode DPPH dan penentuan aktivitas sebagai tabir surya dengan parameter nilai SPF.
 Hasil penelitian menunjukkan bahwa ekstrak terpurifikasi daun wangon mempunyai nilai IC50 41,98 µg/mL lebih baik jika dibandingkan dengan ekstrak kasar dengan IC50 65,32 µg/mL. Sediaan serum mempunyai nilai IC50 71,30 µg/mL dan tergolong antioksidan kuat. Setelah sediaan disimpan selama 30 hari potensi antioksidannya tetap stabil. Selain itu serum tersebut juga mempunyai potensi sebagai tabir surya dengan nilai SPF 19,50±0,02 yang kategorikan memberikan perlindungan menengah terhadap sinar UV B.

UV-Visible Spectrophotometric Determination of Lambda-Cyhalothrin Insecticide in Vegetables, Soil and Water Samples

In modern age pesticide is used widely in agriculture. Lambda-cyhalothrin (LCT) is one of the most used pesticides which are used as a insecticide to kill pest, tricks, flies etc in agricultural field and it is also used for crop production. We have developed new method to detect LCT insecticide in agriculture field and reduce its uses. In this method we found the maximum absorbance at 460 nm for yellow colour dye. We also calculated limit of detection and limit of quantification 0.001 mg kg-1 and 0.056 mg kg-1 respectively. Molar absorptivity and Sandell’s sensitivity was also calculated and obtained 1.782 ×107 mol-1 cm-1 and 9.996 ×10-6 µg cm-2 respectively. The obtained yellow colour dye obeyed Beer’s law limit range of 0.5 µg ml -1 to 16 µg ml-1 in 25 ml. This method is less time consuming, selective, simple, sensitive and low cost. Present method is successfully applied in various soil, water and vegetable samples.

Supramolecular solvent-based microextraction of Sudan Orange G at trace levels for its separation, preconcentration and spectrophotometric determination

ABSTRACT A novel, fast and accurate separation-preconcentration method for supramolecular liquid phase microextraction of sudan orange G dyestuff prior to its UV-vis spectrophotometric determination was developed. Sudan orange G in the model solution was extracted to the supramolecular solvent phase at pH 4.0. Supramolecular solvent used in this study was prepared from tetrahydrofuran (THF) and decanoic acid. Sudan orange G concentration was measured in the UV-Vis spectrophotometer at 380 nm. The sample volume, pH, matrix effect, centrifugation time, ultrasonic bath time, supramolecular solvent volume has been optimised and the work was done under these conditions. The relative standard deviation % value was found below 5%. In this study, the limit of detection (LOD) value and preconcentration factor were found to be 3.4 μgL−1 and 40, respectively. The presented supramolecular liquid phase microextraction procedure was applied to artificial sweat samples and water samples.

Validated UV-Vis Spectrophotometric Determination of Andrographolide in Herbal Nano-Preparation

Determination of major bioactive compounds in polyphyto-formulation is important for production of standardized herbal products. A fast, simple and inexpensive method for detection and quantification of andrographolide concentration in nanoemulsion preparations containing a combination of Andrographis paniculata (Burm f.) Ness. and Phyllanthus niruri L. has been developed. Detection and quantification were carried out using UV-vis spectrophotometry analysis with picric acid reagent and NaOH (8:2) in methanol solvents, read at maximum wavelength 479 nm with 22 min of incubation time. Validation was done by determine the parameters such as linearity, intra and interday precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). The results obtained showed linearity with r = 0.9945 (y = 0.0109x − 0.2066) in the range of 30-80 μg/mL. The accuracy (recovery) varied in the range of 97.15 to 104.42 %. Percentage of relative standard deviation (% RSD) for precision and intermediate precision value were 3.23 and 3.02 % with LOD value 211 μg/mL and the LOQ 705 μg/mL. As a conclusion, this method is suitable to detect andrographolide content in herbal nano-preparation.