Visible Spectrophotometric Method Research Articles

Validation of UV–Vis spectrophotometric and colorimetric methods to quantify methotrexate in plasma and rat skin tissue: Application to in vitro release, ex vivo and in vivo studies from dissolving microarray patch loaded pH-sensitive nanoparticle

This research transformed MTX into smart nanoparticles that respond to the acidic conditions present in inflammation. These nanoparticles were then incorporated into a patch that dissolves over time, aiding their penetration. A method using UV–Vis spectrophotometry was validated to support the development of this new delivery system. This method was used to measure the quantity of MTX in the prepared patches in various scenarios: in laboratory solutions with pH 7.4 and pH 5.0, in skin tissue, and plasma. This validation was conducted in laboratory studies, tissue samples, and live subjects, adhering to established guidelines. The resulting calibration curve displayed a linear relationship (correlation coefficient 0.999) across these scenarios. The lowest quantity of MTX that could be accurately detected was 0.6 µg/mL in pH 7.4 solutions, 1.46 µg/mL in pH 5.0 solutions, 1.11 µg/mL in skin tissue, and 1.48 µg/mL in plasma. This validated method exhibited precision and accuracy and was not influenced by dilution effects. The method was effectively used to measure MTX levels in the developed patch in controlled lab settings and biological systems (in vitro, ex vivo, and in vivo). This showed consistent drug content in the patches, controlled release patterns over 24 h, and pharmacokinetic profiles spanning 48 h. However, additional analytical approaches were necessary for quantifying MTX in studies focused on the drug's effects on the body's functions.

Tea (Camellia sinensis) cultivated in three agro-ecological regions of Bangladesh: Unveiling the variability of methylxanthine, bioactive phenolic compound, and antioxidant activity

Tea (Camellia sinensis) is a widely consumed beverage known for its numerous health benefits, largely attributed to its rich content of quality determining secondary metabolites such as methylxanthine compounds and bioactive phenolic compounds. The goal of this study was to find out variations of the levels of methylxanthines, bioactive phenolic compounds, and antioxidant activity in methanolic and hot water extracts of 129 tea samples grown in three different ecological regions of Bangladesh named Panchagar, Sylhet, and Chattogram. Methylxanthine and bioactive phenolic compounds were determined by using HPLC-DAD, and the antioxidant profile was analysed by UV–vis spectrophotometric methods for methanol and hot water extracts of tea leaves. The IC50 values showed the trend as Panchagar > Sylhet > Chattogram and Sylhet > Chattogram > Panchagar for water and methanol extract, respectively. The results revealed significant (p < 0.05) variations in the levels of methylxanthines content: Panchagar > Chattogram > Sylhet. Caffeine was significantly higher (103.02 ± 5.55 mg/g of dry extract) in the methanolic extract of tea leaves of Panchagar district and lower (53.33 ± 4.30 mg/g of dry extract) in the hot water extract of Sylhet district. Panchagar and Chattogram possessed significantly (p < 0.05) higher catechin content for methanol (57.01 ± 5.50 mg/g dry extract) and hot water (55.23 ± 4.11 mg/g dry extract) extracts, respectively. The utilization of canonical discriminant functions yielded highly favorable outcomes in the classification of tea from three distinct cultivation origins in Bangladesh, relying on their inherent features. This study demonstrated the potential effects of geographical variations on the bioactive compounds and antioxidant properties of tea, emphasizing the importance of regional differences in tea cultivation for optimizing its health benefits as well as dispersing tea cultivation across the country.

Usability of simplified UV–Vis spectrophotometric methods for the determination of nitrate in the presence of organic matter and chloride as interfering factors

Abstract The presence of nitrate in groundwater and surface water in concentrations above levels suitable for human consumption is an increasingly common problem. This is mainly due to human activity, such as the excessive use of fertilizers and the inadequate deactivation of pits. Water analysis laboratories very often carry out analyses to determine nitrate to control the presence of this anion in water intended for human consumption. One of the most commonly used methods is spectrophotometry, both with commercially available kits and by direct measurement of specific wavelengths. However, in these methods, the presence of organic matter and chloride can influence the results obtained. Thus, in this study, the applicability of the simplification (without acidification) of two methods for the determination of nitrate in water by ultraviolet–visible absorbance was verified in the presence of the above-mentioned interfering factors, and it was found that the absorbance method at 220 nm corrected for the absorbance at 275 nm, in its simplified form without acidification, can be used with concentrations of organic matter of 20 mg L−1 for high nitrate concentrations (10 mg L−1 NO3-N).

Spectrophotometric quantification of amitriptyline hydrochloride in pharmaceutical tablets: method development and validation

AbstractThe development and validation of two uncomplicated, selective, and non-extraction-based visible spectrophotometric methods was carried out for the quantification of a tricyclic antidepressant amitriptyline hydrochloride as pharmaceutical tablets as well as in its pure form. The methods rely on the formation of ion pair complexes between amitriptyline base and two acidic dyes, bromothymol blue and bromocresol purple, which were subsequently measured at 410 and 400 nm, respectively. The developed methods included numerous reaction variables that were examined and improved. Beer's law is applicable under optimal conditions for the bromothymol blue and bromocresol purple methods, respectively, over concentrations from 0.5 to 12.5 μg mL−1 and from 0.5 to 10.0 μg mL−1 amitriptyline hydrochloride. The computed values of molar absorptivity were 1.79 × 104 and 2.32 × 104 L.mol−1.cm−1 for bromothymol blue and bromocresol purple methods, respectively, with Sandell’s sensitivity values of 0.0155 and 0.0119 μg cm−2. Both detection limits and quantification limits were computed and determined to be 0.55 and 1.67 μg mL−1 for bromothymol blue method, and 0.49 and 1.49 μg mL−1 for bromocresol purple method, respectively. The developed methods were successfully applied to estimate the concentration of amitriptyline hydrochloride in bulk form and commercial pills. Therefore, these methods demonstrate promising potential for testing this drug in labs for quality control. Graphical abstract Spectrophotometric quantification of amitriptyline hydrochloride in pharmaceutical tablets: method development and validation

Heterometallic bridged Pt(II)‐Zn(II) complexes: Influence of the substituent in 4′‐position in inert terpy ligand on antigenotoxicity, potential antitumor activity and mechanism of interactions of the complexes with biomolecules

The synthesis and characterization of novel hetrometallic complexes [{cis‐PtCl(NH3)2(μ‐4,4′‐bipyridyl)ZnCl(terpy‐Cl)}](ClO4)2 (C1a), [{trans‐PtCl(NH3)2(μ‐4,4′‐bipyridyl)ZnCl(terpy)}](ClO4)2 (C2a), [{cis‐PtCl(NH3)2(μ‐pyrazine)ZnCl(terpy‐Cl)}](ClO4)2 (C3a) and [{trans‐PtCl(NH3)2(μ‐pyrazine)ZnCl(terpy‐Cl)}](ClO4)2 (C4a) (where terpy‐Cl = 4′‐chloro‐2,2′:6′,2′′‐terpyridine) was done. Acid–base titrations were performed by UV–Vis spectrophotometric method to evaluate the pKa values of corresponding aqua complexes. Interactions between complexes and important biomolecules, guanosine‐5′‐monophosphate (5′‐GMP) and glutathione (GSH) were examined by 1H NMR spectroscopy. The chloride substituent at the 4′ position on the middle pyridine ring of terpyridine ligand significantly affects the coordination of biomolecules, as well as overall stability of complexes. The complexes were evaluated in vitro for the antioxidant prevention of DNA damages. All tested novel complexes demonstrated a significant reduction in DNA damage against oxidative modifications of DNA caused by the hydroxyl and peroxyl radicals. Also, cytotoxicity evaluation showed that significant cytotoxicity occurs only after long‐term effect of C1a, C2a and C3a, complexes in HCT‐116 cells. Molecular docking studies predict results in agreement with experimental research.

Physical and Chemical Scrutiny of Obizi River in Awka South Local Government Area of Anambra State, Nigeria for Domestic Consumption

The Obizi River in the Awka South Local Government Area of Anambra State was examined physically and chemically to evaluate its contamination level and suitability for home use. It is important for recreational, fishing, cooking, drinking, and other applications. Its typical applications for drinking, cooking, fishing, recreational activities and other uses are limited since it flows through a canal that might be contaminated by industrial, agricultural, and other human activities. Nitrate mg/l, nitrite mg/l, magnesium mg/l, zinc mg/l, total dissolved solid (TDS) mg/l, hardness mg/l, sulphate mg/l, phosphate mg/l, alkalinity mg/l, acidity mg/l, sodium mg/l, biological oxygen demand (BOD) mg/l, chemical oxygen demand (COD) mg/l, total suspended solid (TSS) mg/l, TS mg/l, oxygen demand (OD) mg/l, and potassium mg/l are among the parameters that were evaluated. Total dissolved solids (TSS) were calculated as the difference between total solids and total dissolved solids. The zinc and nitrate elements within the samples were measured using the ultraviolet (UV) VIS spectrophotometric method. Sulphate was determined turbidimetrically by the absorption spectrophotometry. Magnesium content, total hardness, and alkalinity were measured through titration. TDS (mg/L) was measured with a Multi-Meter (HI 991300, Hanna Equipments, Romania), potassium and sodium ions were assessed by flame photometric technique, chemical oxygen demand (COD) was identified photometrically using the SpectroQuant Nova 60 COD cell test (Merck) in the range of 10 – 150 mg/L. Biological oxygen demand (BOD) was determined using the OxiDirect BOD system and total suspended solids (TSS) was calculated as the difference between total solids and total dissolved solids. Phosphates were measured using the ascorbic acid method, total solids were estimated gravimetrically, and oxygen demand (OD) was measured on-site using a dissolved oxygen meter JENWAY-3405 (Manufacturer: Barloworld Scientific Ltd., England). To find out if the results were significant or not, the parameters were subjected to an ANOVA single factor analysis. The analysis's conclusion was that the data were statistically not significant. Since nitrate and OD were above the World Health Organization's (WHO) limit while most other physicochemical parameters were below it, the ANOVA result showed that there was no significant difference between the physicochemical characteristics of the water samples. With the exception of nitrite and OD, which are above the WHO limit for domestic drinking water and other purposes, it was discovered that the majority of the physicochemical parameters fell within the organization's water quality standards for these purposes. As a result, the water quality is not good and should not be drunk unless treated.

The Effect of Extraction Method on Total Flavonoid Content of Ageratum conyzoides Ethanol Extract

This research is a type of comparative research using a quantitative approach. The study population was the population of Bandotan plants in the Kudus and Jepara regions. The organ parts taken from the plant were leaves, while the stems, roots and flowers were not extracted in this study. The extraction method used maceration and soxhletation with 96% ethanol solvent. Furthermore, to determine the total flavonoid content of &lt;em&gt;Ageratum conyzoides &lt;/em&gt;leaf extraction results using the UV Vis Spectrophotometric method, it is known that &lt;em&gt;Ageratum conyzoides &lt;/em&gt;leaf extract using the Soxhletation method has a higher total flavonoid content (0.32% b/v) compared to the Maceration method (0.22% b/v). The results of the total flavonoid test were then analyzed using the &lt;em&gt;Mann Whitney U Test. &lt;/em&gt;Based on the &lt;em&gt;Mann Whitney U Test &lt;/em&gt;shows that the value of Asymp. Sig. (2- tailed) of 0.102 &amp;gt; 0.05. Therefore, it can be concluded that there is no significant difference between maceration and soxhletation extraction methods on total flavonoids of &lt;em&gt;Ageratum conyzoides &lt;/em&gt;extract.

Extraction and Comparison of Anthocyanin Content in Seeds of Different Black Rice Varieties Using Water Bath Solution Extraction Method

Black rice, rare colored rice, is rich in anthocyanins. Black rice anthocyanin is a kind of natural plant pigment, which has the important effects of anti-oxidation, anti-inflammation and anti-cancer, protecting eyesight and promoting cardiovascular health. Fifteen representative black rice seeds in Southern Henan were used as test materials, and were determined and analyzed by using rice huller, visible light spectrophotometer and water bath solution extraction method and microwave assisted extraction method. The results showed that the anthocyanin content of different varieties of black rice varies greatly, among which the anthocyanin content of black fragrant glutinous rice No. 2 was the highest (0.4258%), and that of black fragrant glutinous rice No.4 was the lowest (0.0207%). The average content of anthocyanin in seeds of black rice varieties tested in Southern Henan Province was 0.1925%. Therefore, the above research results provide important clues for the genetic breeding and improvement of high-quality black rice varieties in Southern Henan. At the same time, varieties with higher anthocyanin content in black rice can be considered as backbone parents for new breeding high-quality black rice.

In vitro biodistribution studies on clinically approved FGFR inhibitors ponatinib, nintedanib, erlotinib and the investigational inhibitor KP2692

Binding towards human serum albumin (HSA) and α1-acid glycoprotein (AGP) of three approved fibroblast growth factor receptor (FGFR) inhibitors ponatinib (PON), nintedanib (NIN) and erdafitinib (ERD), as well as the experimental drug KP2692 was studied by means of spectrofluorometric and UV–visible spectrophotometric methods. Additionally, proton dissociation processes, lipophilicity, and fluorescence properties of these four molecules were investigated in detail. The FGFR inhibitors were predominantly presented in their single protonated form (HL+) at pH 7.4 (at blood pH). At gastric pH (pH 1–2) the protonated forms (+1 – +3) are present, which provide relatively good aqueous solubility of the drugs. All of the four inhibitors are highly or extremely lipophilic at pH 7.4 (logD7.4 ≥ 2.7). At acidic pH 2.0 PON and ERD are rather lipophilic, NIN is amphiphilic, while KP2692 is highly hydrophilic. All four compounds bind to HSA and AGP. Moderate binding of PON, KP2692 and NIN was found towards albumin (logK’ = 4.5–4.7), while their affinity for AGP was about one order of magnitude higher (logK’ = 5.2–5.7). ERD shows a larger affinity for both proteins (logK’HSA ≈ 5.2, logK’AGP ≈ 7.0). The computed constants were used to model the distribution of the FGFR inhibitors in blood plasma under physiological and pathological (acute phase) conditions. The changing levels of the two proteins under pathological conditions compensate each other for PON and NIN, so that the free drug fractions do not change considerably. In the case of ERD the higher AGP levels distinctly reduce the free available fraction of the drug. Comparison with clinical pharmacokinetic data indicates that the here presented solution distribution studies can very well predict the conditions in cancer patients.

Development of Visible Spectrophotometric Methods for the Determination of Tricyclic Antidepressants Based on Formation of Molecular Complexes with p-Benzoquinones

Tricyclic antidepressants are commonly employed in the management of major depressive disorders. The present work describes two visible (VIS) spectrophotometric techniques that utilize the formation of charge transfer complexes between four antidepressant compounds, namely, amitriptyline hydrochloride (AMI), imipramine hydrochloride (IMI), clomipramine hydrochloride (CLO), and trimipramine maleate (TRI) acting as electron donors and two p-benzoquinones, namely, p-chloranilic acid (pCA) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), serving as electron acceptors. The stoichiometry of the compounds produced exhibited a consistent 1:1 ratio in all instances, as established by Job’s method. Molar absorptivities, equilibrium association constants, and several other spectroscopic properties were determined for all complexes. The developed spectrophotometric techniques were validated intra-laboratory and successfully applied for quantitative assessment of the four antidepressant active ingredients in several commercial pharmaceutical formulations. The methods are relatively simple, fast, and use readily available laboratory instrumentation, making them easily applicable by most quality control laboratories worldwide.

Development of Visible Spectrophotometric Method and its Validation for Dolutegravir in Tablet Dosage Form

Objective: There are several methods for analyzing the same, however, they are time-consuming and costly. We created a new spectrophotometric method for determining Dolutegravir (DLT) in tablet dosage forms that is simple, accurate, and precise. We developed and validated a simple, accurate, and precise colorimetric method for the quantitative analysis of Dolutegravir in bulk and dosage form by ICH recommendations in this study. Methodology: There are several methods for analyzing the same, however, they are time-consuming and costly. We created a new spectrophotometric method for determining Dolutegravir (DLT) in tablet dosage forms that is simple, accurate, and precise. In methanol, the initial stock solution of Dolutegravir was prepared. The method is based on the formation of a blue color chromogen complex from Dolutegravir oxidation-reduction with Ferric chloride in the presence of potassium ferricyanide. Result: The color complex was measured at 710nm. Beers law was observedin the concentration range of 3.5-6.5μg/ml witha coefficient of correlation (R2) was 0.998. The system suitability criteria were found to be within the limits. The LOD and LOQ were found to be 0.91 and 2.47, indicating that the method is sensitive. Conclusion: The relative standard deviation (RSD) and percent recovery values were found to be satisfactory, indicating that the proposed method is suitable, accurate, and precise and that it can be used in routine analysis of Dolutegravir in tablet dosage forms, with relatively low-cost solvents.

A New Colorimetric Development and Validation of Visible Method for Estimation of Atorvastatin in Bulk Formulation

A simple, sensitive, accurate, precise and economical visible Spectrophotometric method was developed and validated for the estimation of Atorvastatin in Bulk form. The method is based on the reaction of Atorvastatin with MBTH Reagent [3-Methyl-2-Benzothiazolinone Hydrazone] in the presence of ferric chloride giving greenish blue colour chromogen which shows maximum absorbance at 566nm against reagent blank. The Chromogen obeyed Beer’s law in the concentration range of 5-25 µg/ml for Atorvastatin. The results of the analysis have been validated statistically and recovery studies confirmed the accuracy of the proposed method.

Harnessing MoS2 nanomaterials for TNP sensing and anticancer efficacy

This research article addresses the security concerns related to public safety and national security, focusing on the urgent need for rapid and sensitive explosive detection methods, particularly for 2,4,6-trinitrophenol (TNP) due to its impact on healthcare, environment, and homeland security. The study presents a stable and cost-effective solution based on MoS2 nanomaterials for the detection of TNP using both electrochemical and UV–Vis spectrophotometric methods. Notably, TNP can cause skin irritation, eye damage, respiratory issues and ultimately cancer. The proposed smart nanotechnology-based system effectively detects TNP in the environment and exhibits cytotoxicity against CAL-51 and Huh-7 cells with GI 50 value of 285.48 ± 0.06 μg/ml and 78.125 μg/ml, respectively. Both sensing platforms showcased remarkable results in terms of sensitivity, selectivity, replicability, aging, and real sample application. The unique sensing platform demonstrated excellent sensitivity and selectivity within a linear range of 0.001 mM–1 mM, with a low detection limit of 0.013 μM. The real sample application confirmed the potential of MoS2 for TNP detection and its capability to outperform conventional sensing approaches. This research contributes to advancing explosive detection technology for enhanced security and safety measures.

Analisis Kuantitatif Hidrokuinon pada Krim Pemutih di Kota X Menggunakan Spektrofotometri UV–Vis

Whitening cream is a cosmetic product containing organic chemicals or other substances which are used to whiten the face or remove black spots on the skin. Whitening cream has many benefits for sufferers of skin disorders, namely being able to whiten and remove black marks. Meanwhile, the concept of beauty circulating in society is having white skin. This stigma makes people, especially teenagers, justify any means to get white skin. One way to beautify your skin is to use skin whitening and lightening products. The aim of this research was to determine hydroquinone levels in whitening cream in X City using UV–vis spectrophotometry. The method used in this research is quantitative using the UV–vis spectrophotometric method. The research results showed that all of the 15 samples tested were positive for containing hydroquinone with the highest percentage of hydroquinone found in S1, S5, and S10 with a percentage of 0.0581%; 0.062%; and 0.0501%. Meanwhile, samples with low percentages were in S4, S6, S7, and S12 with a percentage gain of 0.011%; 0.0134; 0.0103%; and 0.0105%. It can be concluded that the hydroquinone levels of the 15 whitening cream samples do not meet the requirements permitted by BPOM No. 23 of 2019, namely 0%.

Overview of Analytical Methods for the Determination of H2 Receptor Blockers: A Review

Overview of various analytical methods for estimating anti-histaminic (H2 Receptor blockers) drugs, particularly for determining their concentration percentage (assay) by analytical methods developed on analytical instruments i.e., UV visible Spectrophotometer, High-Performance Liquid Chromatography, and Hyphenated techniques. The review includes a literature survey of H2 receptor blocker drugs namely cimetidine (Tagamet), ranitidine (Zantac), famotidine (Pepcid, Pepcid AC), and nizatidine (Axid). The examined literature survey addressed chromatographic (HPLC) and UV visible spectrophotometric methods with LC-MS/MS methods used in pure forms, pharmaceutical formulations, human plasma, and other biological fluids for their estimation. In the case of validation parameters, mostly Linearity, Recovery study, LOD, and LOQ were considered and mentioned. This review helps researchers to get detailed information regarding various analytical methods of development and validation for H2 receptor antagonists.&#x0D; Keywords: H2 Receptor blockers, HPLC, Analytical methods, ranitidine, famotidine, nizatidine.

Effect of Red Bajakah Tampala Flavonoid Concentration as Antibacterial on Bacillus subtilis

Red bajakah tampala (Spatholobus littoralis Hassk.) is one type of bajakah that the Dayak people use as traditional medicine. Red bajakah tampala roots contain chemical compounds, namely flavonoids, which have antibacterial activity. This study aims to determine the effect of flavonoid concentration of red bajakah tampala root extract on the inhibitory power of Bacillus subtilis bacteria and the length of survival time. Bajakah root extract is obtained by decoctation method. The flavonoid content contained in bajakah extract was determined using the visible spectrophotometric method. The particle size was determined by a particle size analyzer (PSA), and the inhibition was tested by the Kirby Bauer technique. In an effort to identify bajakah root extract, density, viscosity, and refractive index were measured. The test results using the visible spectrophotometric method showed that the sample had a flavonoid concentration of 16.28 ppm. Meanwhile, the PSA test results showed that the particle size of bajakah extract was 94.6 nm. The antibacterial test results showed that the diameter of the clear zone increased from (6.23 ± 0.03) mm to (7.18 ± 0.06) mm according to the increase in flavonoid concentration from 10 ppm to 30 ppm. The ability of bajakah extract to survive in inhibiting bacteria varied from 48 hours to 72 hours. The results of measurements of density, viscosity, and refractive index are (0,960 0,002) gram/cm3, (0,890 0,010) , dan 1,3350 0,0005 respectively. Keywords: Bacillus subtilis; decoctation; flavonoids; Red bajakah tampala

Effect of Air-Drying Temperature on Phenol Compound and Essential Oils Content in Lemon Leaves

The aim of this workis to study the effect of temperature on the drying kinetics, total phenolic and flavonoid compounds and finally on essential oils existing in lemon leaves. The experimental kinetics data isdivided into five empirical models and the best description is given by Logarithmic equation. For essential oil extraction, the highest yield was obtained at a drying temperature of 24.0°C, an extraction time of 125 min and at a water/vegetable matter ratio of 3.4. Volatile components were identified by GC-MS technique. The outcomes of the experiment indicate that temperature has a significant impact on the components of lemon leaves especially on essential oils. A temperature of 23.7°C produced the highest proportions main compounds (89.26%: Limonene, Monoyloxid, β-pinene). A queous extracts were prepared from the leaves of this plant dried at 30, 40, 50 and 60°C. The quantitative estimation of polyphenols and flavonoids by the UV. Visible spectrophotometer method revealed that the variation in the drying parameters has an influence on the content of these compounds.

DEVELOPMENT AND VALIDATION OF VISIBLE SPECTROPHOTOMETRIC METHOD FOR ESTIMATION OF ELTROMBOPAG OLAMINE IN BULK AND TABLET DOSAGE FORM

A simple and sensitive visible spectrophotometric method has been developed for the quantitative estimation of Eltrombopag Olamine in its bulk and tablet dosage form. It is an orally active ethanolamine salt of Eltrombopag, a smallmolecule, nonpeptide thrombopoietin receptor agonist with megakaryopoiesis-stimulating activity. The maximum absorbance of drug was found at 425nm. Eltrombopag Olamine was found to be dissolved in Methanol so it was used as solvent for the conduction of work. Linearity range for the method was finalized as 3-18 μg/ml with R2 value of 0.9995. % RSD less than 2 which is well within indicates the method is precise and robust. The % recovery rate was found to be 100-101% indicating the method’s accuracy. The method was validated as per ICH guidelines provided and the results were found to be satisfactory. LOD &amp; LOQ values were obtained as 0.150 &amp; 0.456 respectively. Stability studies shows that the drug is unstable in various stress conditions like acid, base, water and oxidation.

Structure and Spectroscopic Studies of Bis Azo Compounds with S/SO2 Bridges and Containing Cyclic-1,3-Dicarbonyl Groups

A series of new bis azo dyes were synthesized starting from aromatic diamine with S/SO2 bridges and cyclic-1,3-dicarbonyl groups; contain active methylene group, namely; 3,3-dimethyl-1,5-cyclohexadione (dimedone), 1,3-cyclohexadione and 2,2-dimethyl-1,3-dioxane-4,6-dione to give 1-6. Whether the reaction is complete and the purity of the compounds were checked with TLC. The structure of the newly synthezed compounds was investigated by using, FT-IR, 1HNMR, LC–MS/MS and UV–Visible spectrophotometric methods, CH3OH was used in the LC-MS/MS experiments, and the molecular masses of the compounds were seen as M and M+1 protonated in the spectrum. In the UV-Vis spectra of these compounds, the solvent effect by using different solvents and also the acid-base effect by adding HCl or KOH to the medium were investigated. The tautomeric equilibrium forms (enol-imine O-H….N, keto-amine O….H-N forms) of the compounds were investigated according to the electronic spectrum recorded in chloroform, dimethylformamide (DMF), acetic acid, and methanol solvents. The results of the UV-visible and 1H-NMR spectra indicated that the compounds in chloroform, dimethylformamide (DMF), acetic acid and methanol were found in the hydrazo tautomer (keto-amine O….H-N forms) of the proposed tautomeric forms.

Determination of Total Phenolic Content of Ethanol Extract of Broken Bone Twigs (Euphorbia tirucalli Linn.) by Folin-Ciocalteu Method Spectrophotometrically

This study aims to determine the total phenolic content of ethanol extracts of Broken Bone Twigs (Euphorbia tirucalli Linn.) Spectrophotometrically. Broken bone twigs (Euphorbia tirucalli Linn.) were extracted using maceration method with ethanol solvent. Total phenolic content was determined using Visible Spectrophotometric method with Folincio-Calteu reagent. The principle of this method is the formation of a blue complex compound of Fossosmolibdat-phosphotungstad reduced phenolic compounds in an alkaline atmosphere that can be measured Spectrophotometrically. As a comparator used gallic acid. From the results of absorbance measurements obtained linear regression equation ŷ = 0.0012x + 0.0316 with a coefficient of determination (R²) of 0.9661. Phenolic levels in bone fracture twigs (Euphorbia tirucalli Linn.) amounted to 0.102% w/b calculated as gallic acid.