scholarly journals Quantification of Lovastatin Produced by Monascus purpureus

2015 ◽  
Vol 9 (1) ◽  
pp. 6-13 ◽  
Author(s):  
A. Seenivasan ◽  
Sathyanarayana N. Gummadi ◽  
Tapobrata Panda ◽  
Thomas Théodore
Keyword(s):  
Absorption Spectrum ◽  
Spectrophotometric Method ◽  
Hplc Analysis ◽  
Fermentation Broth ◽  
The Other ◽  
Monascus Purpureus ◽  
Interesting Problem ◽  
Experimental Conditions ◽  
Novel Method ◽  
Uv Visible

Development of a novel method for the quantification of lovastatin is an interesting problem in the analytical field. In the literature, many reports use spectrophotometric method for the quantification of lovastatin. However, the analysis of fermentation broth containing lovastatin appears to be inaccurate using spectrophotometric method. Hence, the estimation of lovastatin produced by Monascus purpureus and pure lovastatin was attempted by UV-visible spectrophotometer as well as HPLC. It was observed that the analogues and/or intermediates of lovastatin synthesized in the fermentation broth and the products of fermentation caused superimposition effect on the absorption spectrum. Phosphate is a medium constituent for the production of lovastatin by the organism which contributed significantly to the superimposition of absorption spectrum. On the other hand, HPLC analysis consistently gave reliable results for the estimation of lovastatin under all the experimental conditions studied.

scholarly journals DEVELOPMENT AND VALIDATION OF UV-VISIBLE SPECTROPHOTOMETRIC METHOD FOR DETERMINATION OF DULOXETINE

2019 ◽  
pp. 27-31
Author(s):  
LIPSA SAMAL ◽  
AMARESH PRUSTY
Keyword(s):  
Spectrophotometric Method ◽  
Spectroscopic Method ◽  
Solvent System ◽  
Spectrophotometric Analysis ◽  
Thiophene Derivative ◽  
Experimental Conditions ◽  
Relative Standard ◽  
Uv Visible ◽  
Development And Validation

Objective: The aim of the present work was to develop and validate a simple UV spectroscopic method for the determination of duloxetine, which is a thiophene derivative and a selective neurotransmitter reuptake inhibitor for serotonin, norepinephrine, and to lesser degree dopamine. Methods: The UV Spectrophotometric analysis was performed using Shimadzu UV-1800 and Shimadzu UV-1700 spectrophotometer by using solvent system acetonitrile and water in the ratio of 8:2. Detection was performed at a wavelength of 290 nm. Method validation was carried out according to ICH Q2R1 guidelines by taking the parameters linearity, accuracy, precision, ruggedness, and robustness, LOD and LOQ. Results: The UV Spectrophotometric method was found linear in the range of 10-50 μg/ml. The method was rugged and robust with % relative standard deviation less than 2. The extraction recoveries were found to be higher than 99% in all experimental conditions. Conclusion: Based upon the performance characteristics, the proposed method was found accurate, precise and rapid and suitable for the determination of Duloxetine for routine analysis.

scholarly journals Comparison of Analytical Methods for Determining Methylesterification and Acetylation of Pectin

2021 ◽  
Vol 11 (10) ◽  
pp. 4461
Author(s):  
Yang Yu ◽  
Yuwen Wang ◽  
Xianbin Liu ◽  
Ying Liu ◽  
Li Ji ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Structural Analysis ◽  
Galacturonic Acid ◽  
Hplc Analysis ◽  
The Other ◽  
Sample Treatment ◽  
Citrus Pectin ◽  
Experimental Conditions ◽  
Ft Ir ◽  
Comparison Of Analytical Methods

The esterification of galacturonic acid with methanol and/or acetic acid is important for the structural analysis of pectin. Although several methods have been reported for determining the degree of methylesterification (DM) and acetylation (DAc), the present study compares and optimizes three methods (titration, FT-IR and HPLC) using commercial citrus pectin (CP). Our results showed that the DM of CP was 47.0%, 47.6% and 48.0% as determined by titration, FT-IR and HPLC, respectively, suggesting that DM determination is nearly identical using any of these methods. However, the titration approach requires more sample than the other two. HPLC showed that the DAc of CP was 1.6%, an approach that can be used to determine the DM and DAc of pectin simultaneously. Here, we simplified and optimized sample treatment for HPLC analysis and compared it with the reported literature. Our results provide useful information for choosing appropriate methods for determining the DM and DAc of pectin based on various sample properties and experimental conditions.

scholarly journals UV SPECTROPHOTOMETRIC ANALYSIS AND VALIDATION OF OSELTAMIVIRPHOSPHATE IN PURE AND PHARMACEUTICAL FORMULATION

2020 ◽  
pp. 111-114 ◽  
Author(s):  
SACHIN A. YANJANE ◽  
SHRISHAIL M. GHURGHURE ◽  
VINOD K. MATOLE
Keyword(s):  
Spectrophotometric Method ◽  
Spectrophotometric Analysis ◽  
Pharmaceutical Formulation ◽  
Ich Guidelines ◽  
Highly Sensitive ◽  
Double Beam ◽  
Recovery Study ◽  
Uv Visible ◽  
Oseltamivir Phosphate ◽  
Simple Economic

Objective: A new, simple, economical, precise, sensitive, linear, accurate, rapid UV spectrophotometric method has been developed for the estimation of Oseltamivir Phosphate in pure form and pharmaceutical formulation. Methods: This UV method was developed using Methanol as a solvent. In the present method, the wavelength selected for analysis was 218 nm. UV-Visible double beam spectrophotometer (Systronic 2201) was used to carry out spectral analysis. The ICH guidelines were used to validate the method. Results: The method was validated for linearity, range, accuracy, precision, robustness, LOD and LOQ. Linearity was found in the range of 10-50µg/ml. Accuracy was performed by using a recovery study. The amount of drug recovered was found to be in the range of 99.01-100.1%. The % RSD value was found to be less than 2. Conclusion: The developed UV spectrophotometric method was found to be simple, economic, sensitive, easy, accurate, linear, specific and highly sensitive and can be used for routine estimation of Oseltamivir Phosphate.

Intercalation Processes in Cobalt Substituted Nickel Oxyhydroxides

1990 ◽  
Vol 210 ◽  
Author(s):  
Claude Delmas
Keyword(s):  
Ir Spectroscopy ◽  
Mechanical Treatment ◽  
Positive Charge ◽  
Van Der Waals ◽  
The Other ◽  
Hydrolysis Reaction ◽  
Water Molecules ◽  
Layered Oxides ◽  
Experimental Conditions ◽  
Cobalt Ions

AbstractChimie douce reactions (hydrolysis and reduction) from layered oxides : NaNiO2, NaxCoO2 and NaNil-xCoxO2 lead to numerous oxyhydroxides and hydroxides which differ by the composition of the intersheet space.According to the experimental conditions of the hydrolysis reaction, the oxyhydroxides can be unhydrated or intercalated with one or two layers of water molecules. From the most hydrated phases, the other ones can be obtained by chemical, thermal and even mechanical treatment.The reduction of Co-substituted nickel oxyhydroxides leads to hydroxides in which nickel and cobalt ions are respectively divalent and trivalent. In order to compensate the excess of positive charge in the (Ni, Co)O2 sheet, anions (OH-, CO32-, SO42-, NO3-) are inserted in the Van der Waals gap.For the highest anion amounts, well ordered α*-type materials are obtained. Water molecules are simultaneously inserted in the interslab space. Their structure is strongly related to the hydrotalcite one. When the amouit of anions in the intersheet space is not sufficient, interstratified materials are obtained. In this case the (Ni,Co)(OH)2 slabs are separated by a layer of CO32- anions and water molecules (α*-type) or by an empty Van der Waals gap (β(II)-type). The amount of α*-type planes in the structure increases with the cobalt amount. All these materials have been characterized by IR spectroscopy which allows to detect the existence of two types of O-H bonds (free in α*-type plane or hydrogen bonded in ²(II)-type plane).

scholarly journals The spectrum of thallium fluoride

1937 ◽  
Vol 160 (901) ◽  
pp. 242-253 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Kinetic Energy ◽  
The Other ◽  
Molecular Spectra ◽  
Absorption Tube ◽  
Saturated Vapour ◽  
Long Wave ◽  
Original Investigation ◽  
Wave Edge

This study of the thallium fluoride spectrum was undertaken as part of a detailed investigation into the molecular spectra of the series of heavy diatomic fluorides HgF, TlF, PbF and BiF. Whereas the spectra of PbF (Rochester 1936) and BiF (Howell 1936), of which analyses have already been published, contain no very unusual features the TlF spectrum is particularly rich in them, so that it has seemed desirable to extend the original investigation in order to include the other halides of thallium. The absorption spectrum of the fluoride has already been examined by Boizova and Butkow (1936), their findings being summarized below: 1— A continuum at 2200 A appears when the absorption tube is at a temperature of 155° C. Its long-wave edge moves towards the red with increase of temperature, being at 2700 for the unsaturated vapour and at 3400 for the saturated vapour when the temperature is 280° C. They attributed this continuum to the dissociation of Tl 2 F 2 . Tl 2 F 2 → 2TlF + kinetic energy.

Unusual spectral shifts in the prototropic reactions of 2,7-diaminofluorene

1987 ◽  
Vol 65 (9) ◽  
pp. 2013-2018 ◽  
Author(s):  
R. Manoharan ◽  
Sneh K. Dogra
Keyword(s):  
Absorption Spectrum ◽  
Aqueous Medium ◽  
Fluorescence Spectrum ◽  
Blue Shift ◽  
Proton Donor ◽  
Red Shift ◽  
The Other ◽  
Spectral Shifts ◽  
Other Hand

The red shift observed in the absorption spectrum of 2,7-diaminofluorene (DAF) in ether and acetonitrile is either due to the proton-donating capacity of the solute or due to its dispersive interactions with the solvent and a blue shift in methanol and water is due to the proton-accepting nature of DAF. DAF acts as a proton donor in S1 state in all solvents. The red shift in the fluorescence spectrum of the monocation of DAF relative to that of DAF is not because of the —NH2 group becoming more basic but because of the large solvent relaxating in aqueous medium. On the other hand, the monocation of DAF in cyclohexane follows the normal blue shift in the fluorescence spectrum. pKa values for the various prototropic reactions in S0 and S1 states are determined and discussed.

Development and Validation of UV-Visible Spectrophotometric method for the Estimation of Curcumin and Tetrahydrocurcumin in Simulated Intestinal Fluid

2021 ◽  
pp. 2971-2975
Author(s):  
Jai Bharti Sharma ◽  
Sherry Sherry ◽  
Shailendra Bhatt ◽  
Vipin Saini ◽  
Manish Kumar
Keyword(s):  
Drug Release ◽  
Spectrophotometric Method ◽  
Tween 80 ◽  
Solvent System ◽  
Intestinal Fluid ◽  
Simulated Intestinal Fluid ◽  
Validation Parameters ◽  
Administration Method ◽  
Uv Visible ◽  
Development And Validation

Background: Due to solubility issues of curcumin and tetrahydrocurcumin, there is a need for the development of a UV-Visible spectrophotometric method that can estimate the drug release precisely and accurately. The addition of surfactant in the dissolution medium in low concentration achieved bio-comparable surface activity and can be used to estimate the drug release from formulations by avoiding sink conditions. Objective: The purpose of the present investigation was to develop a simple and précise UV-Visible spectrophotometric method for the determination of curcumin and tetrahydrocurcumin after oral administration. Method: A UV-Visible spectrophotometric method was developed using an appropriate solvent system for the estimation of curcumin and tetrahydrocurcumin. The solvent system having simulated intestinal fluid and particular concentration of surfactant was selected and further validated according to guidelines of the international conference on harmonization (ICH), the analytical parameter like linearity, precision and accuracy, etc. were studied. Results: Simulated intestinal fluid pH 7.4 with tween 80 at 1 % concentration satisfied all the conditions relative to peak quality at the stated wavelength for curcumin and intestinal fluid pH 7.4 with tween 80 at 0.5% concentration satisfied all the conditions relative to Peak quality at the stated wavelength for tetrahydrocurcumin. The developed methods were found within the range of all the validation parameters. Conclusion: The proposed method was found to be very simple and precise and can be used for routine quantitative analysis of curcumin and tetrahydrocurcumin.

Comparative Phytochemical Research of Solidago Genus: S. graminifolia. Note I. Flavonoids

2018 ◽  
Vol 1 (1) ◽  
pp. 18-26
Author(s):  
Luciana Dobjanschi ◽  
Ramona Păltinean ◽  
Laurian Vlase ◽  
Mihai Babotă ◽  
Luminita Fritea ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Quantitative Determination ◽  
Spectrophotometric Method ◽  
Biological Properties ◽  
The Other ◽  
Indigenous Species ◽  
Solidago Canadensis ◽  
Phytochemical Composition ◽  
Chromatographic Profile ◽  
Solidago Virgaurea

Abstract Solidago graminifolia L. Salisb. is one of the latest species appeared in Romania. Due to the interest for the Solidago species as medicinal plants, we researched its phytochemical composition in comparison with the other three species present in Romania: Solidago virgaurea L., Solidago canadensis L., Solidago gigantea Aiton. Starting from the chemotaxonomic value of flavonoids, and their valuable biological properties, we wanted to analyze these substances from S. graminifolia compared to other Solidago species in Romanian flora. The studied species have a high content of flavonoids (3.44-5.21%). The flavonoid substances identified in the indigenous species of Solidago have a high chemotaxonomic value, each species having a charateristic chromatographic profile, therefore their analysis is useful in the case of adulterations. The qualitative analysis of flavonoids was performed by TLC and HPLC-MS, mean while the quantitative determination was achieved by spectrophotometric method and individual fractions separated by HPLC-MS.

scholarly journals DEVELOPMENT AND VALIDATION OF UV-SPECTROPHOTOMETRIC METHOD FOR ESTIMATION OF HYDROQUINONE IN BULK, MARKETED CREAM AND PREAPARED NLC FORMULATION

2017 ◽  
Vol 9 (5) ◽  
pp. 102
Author(s):  
Sukhjinder Kaur ◽  
Taranjit Kaur ◽  
Gurdeep Kaur ◽  
Shivani Verma
Keyword(s):  
Spectrophotometric Method ◽  
Limit Of Detection ◽  
Pharmaceutical Formulations ◽  
Pure Form ◽  
Nanostructured Lipid Carrier ◽  
Limit Of Quantification ◽  
Double Beam ◽  
Uv Visible ◽  
Development And Validation

Objective: The aim of the present work was to develop a simple, rapid, accurate and economical UV-visible spectrophotometric method for the determination of hydroquinone (HQ) in its pure form, marketed formulation as well as in the prepared nanostructured lipid carrier (NLC) systems and to validate the developed method.Methods: HQ was estimated at UV maxima of 289.6 nm in pH 5.5 phosphate buffer using UV-Visible double beam spectrophotometer. Following the guidelines of the International Conference on Harmonization (ICH), the method was validated for various analytical parameters like linearity, precision, and accuracy robustness, ruggedness, limit of detection, quantification limit, and formulation analysis.Results: The obtained results of the analysis were validated statistically. Recovery studies were performed to confirm the accuracy of the proposed method. In the developed method, linearity over the concentration range of 5-40 μg/ml of HQ was observed with the correlation coefficient of 0.998 and found in good agreement with Beer Lambert’s law. The precision (intra-day and inter-day) of the method was found within official RCD limits (RSD<2%).Conclusion: The sensitivity of the method was assessed by determining the limit of detection and limit of quantification. It could be concluded from the results obtained that the purposed method for estimation of HQ in pure form, in the marketed ointment and in the prepared NLC-formulation was simple, rapid, accurate, precise and economical. It can be used successfully in the quality control of pharmaceutical formulations and for the routine laboratory analysis.

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