spectroscopic method
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2023 ◽  
Vol 83 ◽  
Author(s):  
S. C. C. Costa ◽  
P. K. F. Damasceno ◽  
R. G. G. Lima ◽  
M. B. Botura ◽  
C. R. C. Branco ◽  
...  

Abstract The antioxidant, photoprotective and antinociceptive Marcetia macrophylla active extract was investigated as an active ingredient in a sunscreen cream formulation. Thus, the M. macrophylla extract showed IC50 of 3.43 mg/ml of the antioxidant (DPPH∙ scavenging test) and Sun Protection Factor of 20.25 (SPF/UV-B, at 250 µg/ml) and UV-A of 78.09% (photobleaching trans-resveratrol test). The antinociceptive activity was superior to all standards tested using the in vivo acetic acid-induced writhing test (99.14% at the dose of 200 mg/kg) and the high-performance liquid chromatography coupled with diode array detector and mass spectroscopy multi-stage (HPLC-DAD-MS/MS) enabled the structural characterization of the quercetin-3-O-hexoside, quercetin-3-O-pentoside and quercetin-3-O-desoxihexoside. The pharmaceutical formulation containing the Marcetia macrophylla crude active extract was prepared and the physicochemical tests (organoleptic characteristics, pH analysis and centrifugation), the in vitro UVB (sun protection factor, SPF) and UVA (β-carotene) using the spectroscopic method were investigated. The formulation showed satisfactory results concerning the physicochemical parameters evaluated and active against the UV test. Thus, M. macrophylla showed biological activities with potential use in pharmaceutical preparations.


2021 ◽  
Vol 37 (6) ◽  
pp. 1488-1492
Author(s):  
Beena Kumari K. S ◽  
Sudha Devi R ◽  
Nayana Senan V

A new Schiff base ligand derived from curcumin and ethylenediamine has been synthesized by the microwave irradiation method. The synthesized ligand was characterized by using FT-IR, UV-VIS, Molar conductance, NMR, PL and DLS studies. The results confirmed that the successful formation of Curcumin Based Schiff Base ligand. The ligand synthesized was stable at room temperature, completely soluble in hot methanol/DMF, partially soluble in ethanol/DMSO/acetone and insoluble in water. The spectra studies of FTIR and UV-visible confirmed the formation of the azomethine group in the ligand. NMR spectrum confirmed the presence of aromatic proton, hydroxyl proton, amine proton etc in the ligand. The luminescent property of the ligand was confirmed by the photoluminescence spectroscopic method. The low molar conductance value showed the non-electrolytic nature of the ligand. The dynamic light scattering studies showed that the ligand synthesized was in nanometer scale. The structure of the ligand was also proposed based on the analysis reports.


INDIAN DRUGS ◽  
2021 ◽  
Vol 58 (11) ◽  
pp. 53-59
Author(s):  
Tukaram M. Kalyankar ◽  
◽  
Shital S. Dange ◽  
Shivraj B. Hambarde ◽  
Shailesh J. Wadher ◽  
...  

A simple, accurate and precise UV spectrometric method has been developed for the simultaneous determination of valsartan and hydrochlorothiazide in tablet dosage form. Spectra of valsartan and hydrochlorothiazide in methanol and water (50:50 V/V) show λ max at 250.0 nm and 271.4 nm, respectively. Valsartan and hydrochlorothiazide are subjected to various stress conditions like acid, alkali, thermal and photolytic degradation. Beer’s law was obeyed in concentration range of 4- 24 µg mL-1 for valsartan and 0.5-3 µg mL-1 for hydrochlorothiazide at their respective wavelengths. The proposed method was successfully applied to tablet dosage form for determination of both drugs. The percentage recovery of valsartan and hydrochlorothiazide were found to be 100.19 % and 99.51 %, respectively. A novel accurate and precise stability indicating spectroscopic method has been developed for estimation of valsartan and hydrochlorothiazide.


Author(s):  
Narender Malothu ◽  
Sowjanya Ravuri ◽  
Balakrishna Muthyala ◽  
Narayana Rao Alla ◽  
Anka Rao Areti

Aim: To develop a simple spectroscopic method for estimation of doxylamine (DOX) succinate in its tablet dosage form and human plasma with the aid of an ion-pair complex formation. Methods: In this method, methyl orange (0.05 % w/v) dye was used to form an ion-pair complex in acetate buffer (1M; pH: 5.00) at 300 C ± 20C. The ion-pair complex formed was extracted with chloroform. The maximum absorbance for the ion-pair complex was measured at 420 nm. Results and discussion: The method conditions were obeyed Beer's law in the concentrations ranging from 5-25 µg/mL of DOX succinate with a correlation coefficient (r2) of 0.992. The ion-pair (drug-dye) complex was formed in a 1:1 ratio which was demonstrated by Jobs' method of continuous variation. The method was satisfied the validation criteria as per ICH (Q2R1) guidelines. Accuracy studies showed 99.06-100.9 % recovery of the analyte. The responses of the precision and robustness were found within acceptable limits (<2% RSD). The LOD and LOQ values were found as 0.31 and 0.939 µg/mL, respectively. Conclusion: The developed method was simple, specific, and economical and requires a short analysis time. Therefore it could be considered for precise analysis of DOX succinate in biological matrices.


INDIAN DRUGS ◽  
2021 ◽  
Vol 58 (10) ◽  
pp. 51-55
Author(s):  
Satish A. Patel ◽  
Bhoomi H. Patel ◽  

A simple, sensitive, accurate, precise and cost-effective pH independent spectrophotometric method has been developed for the estimation of triamcinolone acetonide in nasal sprays. Estimation was carried out at the isosbestic point of drug solutions, Isosbestic point was measured by scanning equimolar solution of triamcinolone acetonide separately in phosphate buffer pH 3.0, phosphate buffer pH 7.0 and phosphate buffer pH 10.0 at a concentration of 10 µg mL-1. They were scanned in the wavelength range of 200-400 nm. The isosbestic point was found to be 230.0 nm in acidic, basic and neutral condition; hence pH independent wavelength 230 nm was used for estimation of triamcinolone acetonide. The method observed linear response in the concentration range of 3-18 µg mL-1 at 230 nm. Developed method has been validated in accordance with ICH guideline Q2 R1 for several parameters like linearity, precision, accuracy, limit of detection and limit of quantification. The developed and validated analytical method was successfully applied to the estimation of triamcinolone acetonide in marketed nasal spray formulations.


2021 ◽  
Vol 11 (5) ◽  
pp. 105-109
Author(s):  
Shivani Soni ◽  
Vivek Jain ◽  
Sunil Kumar Jain ◽  
Pushpendra Kumar Khangar

The primary benefit of a sustained release dosage form compared to a conventional dosage form, is the consistent drug plasma concentration and consequently uniform therapeutic effect. Matrix system are preferential because of their ease, patient compliance etc, than  traditional drug delivery which have several drawbacks like reiterated administration, variation in blood concentration level etc. The aim of the present research study was to develop and evaluate sustained release matrix tablets of furosemide using direct compression method using  natural  gummy  and  waxy  materials (Xanthan  gum, bees  wax)  and synthetic  polymers  (HPMC K4M). The matrix tablet formulations were prepared by using different drug: polymer ratios (1:1, 1:2 and 1:3). All formulations were assessed using micromeritics studies of powder blend and diverse physicochemical tests. All the physicochemical characters of the formulated tablets were within acceptable limits. The release pattern of the drug was viewed over a period of 12 hours and determined the amount of drug by the UV-Visible spectroscopic method. Dissolution data demonstrated that the formulated tablets with Xanthan gum and hydroxyl propyl methylcellulose (HPMC) provided sustained release of the drug up to 12 hrs. Therefore inexpensively it may be appropriate for the pharmaceutical industries to employ this kind of simple technologies for the expansion of advanced formulations. Hence, we conclude that the purpose of this study was to formulate a sustained release matrix tablet of furosemide using diverse polymers and their dissimilar proportions have been attained. Keywords: Furosemide, Direct compression, Natural, Synthetic polymers, Sustained release tablets.


2021 ◽  
Author(s):  
Qiang Wang ◽  
Zhen Wang ◽  
Hui Zhang ◽  
Shoulin Jiang ◽  
Yingying Wang ◽  
...  

Abstract Dual-comb spectroscopy (DCS) has revolutionized optical spectroscopy by providing broadband spectral measurements with unprecedent resolution and fast response. Photothermal spectroscopy (PTS) offers an ultrasensitive and background-free gas sensing method, which is normally performed using a single-wavelength pump laser. The merging of PTS with DCS may enable a new spectroscopic method by taking advantage of both technologies, which has never been studied yet. Here, we report dual-comb photothermal spectroscopy (DC-PTS) by passing dual combs and a probe laser through a gas-filled anti-resonant hollow-core fiber, where the generated multi-heterodyne modulation of the refractive index is sensitively detected by an in-line interferometer. As an example, we have measured photothermal spectra of acetylene over 1 THz, showing a good agreement with the spectral database. Our proposed DC-PTS provides new opportunities for broadband gas sensing with super-fine resolution and high sensitivity, as well as with a small sample volume and compact configuration.


Author(s):  
Priya Subramanian Kalaimani

Abstract: This study aimed to predict the functional group changes in the natural form to hydrogenated form of vegetable oils using FTIR spectroscopic method. The edible oil, which are palm oil, groundnut oil, sesame oil, and vanaspathi(hydrogenated vegetable oil) were observed with relative intensities of the peak and characteristic area percentage of peaks. It is found that trans fatty acids at the peak of 966.34cm-1 in the region of 980-960cm-1 strong C=C bending vibration due to the presence of alkene disubstituted (trans) observed in the hydrogenated form of vegetable oil. Because the nutritional composition of the vegetable oil is intensely reduced and long-term consumption will bringadversative health problems for humans. Keywords: FTIR, Palm oil, Groundnut oil, Sesame oil, Vanaspathi, Transfats


2021 ◽  
Vol 87 (6) ◽  
Author(s):  
A.G. Oreshko

Explanations for the long lifetime of spherically symmetric objects in nature and the short lifetime of laboratory plasma are given. A qualitative description of the relativistic model of ball lightning is also given, which is a spherical electric region with strong electric and magnetic fields. The plasma temperature in the zone of the ball-lightning generation is measured by the spectroscopic method. A large ball lightning, the maximum diameter of which is equal to one meter and which stands in the region of its generation, is also registered after the formation and departure of a high-energy ball lightning. The reason for the low emissive power in the optical range characteristic for the atmospheric ball lightning is explained by the absence of electron transitions in the outer proton-containing shell. The absence of electrical breakdown at ultrahigh electric field between the core and the outer shell of the ball lightning and its destruction at the moment when the resulting force becomes nonzero are also explained.


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