Order Derivative Spectra Research Articles

FIRST DERIVATIVE SPECTROSCOPIC METHOD FOR SIMULTANEOUS ESTIMATION OF MESALAZINE AND RIFAXIMIN IN SYNTHETIC MIXTURE

Objective: The present study was aimed to describe a simple, sensitive, rapid, accurate, precise and economical first derivative spectrophotometric method for the simultaneous determination of Mesalazine (MESA) and Rifaximin (RIFA) in synthetic mixture. Methods: The derivative spectrophotometric method was based on the determination of both the drugs at their respective zero crossing point (ZCP). The first order derivative spectra were obtained in 0.01 N NaOH and the determinations were made at 329.20 nm (ZCP of RIFA) for MESA and 292.80 nm (ZCP of MESA) for RIFA. The linearity was obtained in the concentration range of succinate 10-50 μg/ml for MESA and 10-50 μg/ml for RIFA. Results: The limit of determination was 0.321 μg/ml and 0.301 μg/ml for MESA and RIFA, respectively. The limit of quantification was 0.974 μg/ml and 0.912 μg/ml for MESA and RIFA, respectively. The mean recovery was 100.20 and 99.52% for MESA and RIFA, respectively. The method was found to be simple, sensitive, accurate and precise and was applicable for the simultaneous determination of MESA and RIFA in synthetic mixture. The results of analysis have been validated statistically and by recovery studies. Conclusions: The method was successfully applied to pharmaceutical synthetic mixture which is considered in approved patent which show no interference. The result of analysis has been validated statistically and by recovery studies. So, this method accurate, precise, robust, rugged and economic in nature.

Simultaneous Derivative Spectrophotometric Determination of Lornoxicam and Paracetamolin Tablet Dosage Forms

Lornoxicam and Paracetamol in combined dosage forms (Tablets). The zero crossing point of Paracetamol (247.42 nm) has been selected for the quantification of Lornoxicam whereas the zero crossing point of Lornoxicam (233.28 nm) has been selected for the quantification of Paracetamol from the first order derivative spectrum observed in borate buffer. The method obeys Beer-Lambert’s law over the concentration range 5-50 µg/ml for Lornoxicam and 5-60 µg/ml for Paracetamol. The proposed method was validated and can be used for the analysis of tablet dosage forms containing Lornoxicam and Paracetamol. K ey words: Lornoxicam, Paracetamol, Spectrophotometry, Derivative spectroscopy, Validation.

On computing first and second order derivative spectra

Enhancing resolution in spectral response and an ability to differentiate spectral mixing in delineating the endmembers from the spectral response are central to the spectral data analysis. First and higher order derivatives analysis of absorbance and reflectance spectral data is commonly used techniques in differentiating the spectral mixing. But high sensitivity of derivative to the noise in data is a major problem in the robust estimation of derivative of spectral data. An algorithm of robust estimation of first and second order derivative spectra from evenly spaced noisy normal spectral data is proposed. The algorithm is formalized in the framework of an inverse problem, where based on the fundamental theorem of calculus a matrix equation is formed using a Volterra type integral equation of first kind. A regularization technique, where the balancing principle is used in selecting a posteriori optimal regularization parameter is designed to solve the inverse problem for robust estimation of first order derivative spectra. The higher order derivative spectra are obtained while using the algorithm in sequel. The algorithm is tested successfully with synthetically generated spectral data contaminated with additive white Gaussian noise, and also with real absorbance and reflectance spectral data for fresh and sea water respectively.

Development and validation of a rapid derivative spectrophotometric method for simultaneous determination of acetaminophen, ibuprofen and caffeine

A zero-crossing derivative spectrophotometric method was used for the simultaneous determination of acetaminophen, ibuprofen and caffeine. The derivative spectra of standard solutions of each compound were obtained at different orders to find out the suitable zero-crossing points. Under the optimized conditions, determination of acetaminophen was performed at wavelengths of 311 and 270 nm using the third order (Δλ = 24.5) and fourth order (Δλ = 12.0) derivative spectra, respectively. Ibuprofen and caffeine were determined at wavelengths of 235 and 300 nm using the second order (Δλ = 21.0) and fourth order (Δλ = 27.0) derivative spectra. The method was found to be linear (r2 > 0.998) in the range of (μg/mL) 5–50 for acetaminophen, 5–30 for ibuprofen and 1–7 for caffeine in the presence of other compounds. The within-day and between-day precision and accuracy of the proposed method were acceptable (CV < 3% and error < 2%) for all three components and the proposed method was satisfactory for quality control purposes. The method was successfully applied to the simultaneous determination of acetaminophen, ibuprofen and caffeine in pharmaceutical dosage forms without any interference from excipients and there was no need to any prior separation before analysis.

Photoisomerisation of azobenzene crystals in aqueous dispersions examined by higher order derivative spectra.

Photo-induced UV-Vis spectral changes of azobenzene (Az) in solution and aqueous crystalline dispersions were analysed by means predominantly of fourth order derivatives. Weak bands due to vibration level transitions (VLT) of E-isomers in solution were well-resolved in derivatives to estimate conversion of photoisomerisation by tracing extrema of a VLT sub-peak. The photo-induced derivative-spectral changes of Az crystals dispersed in aqueous PVA solutions generated many common crossing points to indicate that Az dissolves partially in a PVA solution to lead to photoisomerisation in a homogeneous phase and the reversible alteration of particle size. The solid-state photoisomerisation of Az was investigated by the preparation of PVA-free aqueous dispersions of powdery nanohybrids comprised of Az and silica nanoparticles. The fourth order derivatives of spectral changes revealed that the photochemical process involves three kinds of species including non-aggregated and aggregated E-isomers as well as Z-isomers.

Fourier transform infrared spectroscopy combined with chemometrics for discrimination of Curcuma longa, Curcuma xanthorrhiza and Zingiber cassumunar

Turmeric (Curcuma longa), java turmeric (Curcuma xanthorrhiza) and cassumunar ginger (Zingiber cassumunar) are widely used in traditional Indonesian medicines (jamu). They have similar color for their rhizome and possess some similar uses, so it is possible to substitute one for the other. The identification and discrimination of these closely-related plants is a crucial task to ensure the quality of the raw materials. Therefore, an analytical method which is rapid, simple and accurate for discriminating these species using Fourier transform infrared spectroscopy (FTIR) combined with some chemometrics methods was developed. FTIR spectra were acquired in the mid-IR region (4000–400cm−1). Standard normal variate, first and second order derivative spectra were compared for the spectral data. Principal component analysis (PCA) and canonical variate analysis (CVA) were used for the classification of the three species. Samples could be discriminated by visual analysis of the FTIR spectra by using their marker bands. Discrimination of the three species was also possible through the combination of the pre-processed FTIR spectra with PCA and CVA, in which CVA gave clearer discrimination. Subsequently, the developed method could be used for the identification and discrimination of the three closely-related plant species.

First order derivative and dual wavelength spectrophotometry methods development and validation for simultaneous estimation of alogliptin and pioglitazone in bulk and dosage form

Simple, sensitive, rapid and accurate UV spectroscopic methods have been developed for the Simultaneous estimation of Alogliptin and Pioglitazone bulk and pharmaceutical dosage forms. First order derivative and Dual wavelength methods were developed and validated using solvent methanol. Both methods show linearity at 5-30 g/ml. The first order derivative spectra of each solution were obtained. ZCP of Alogliptin was found 275.60 nm and ZCP of Pioglitazone was found 268.20 nm. The zero crossing point (ZCP) of Alogliptin at which Pioglitazone is measured and ZCP of Pioglitazone at which Alogliptin is measured. In Dual wavelength method, spectra two wavelengths 270.20 nm and 265 were selected as ? 1 and ? 2 for the estimation of Alogliptin. Pioglitazone shows the same absorbance at these wavelengths. Similarly, wavelengths 280 nm and 271 nm were selected as ? 3 and ? 4 for estimation of Pioglitazone. Alogliptin shows the same absorbance at these wavelengths. The methods were validated based on ICH guidelines. There are simple, sensitive, and reliable and results are reproducible for the routine analysis of Alogliptin and Pioglitazone.

Individual photoreorientation of non-aggregated and aggregated azobenzene side chains tethered to a liquid-crystalline polymer determined by higher order derivative spectra

The fourth-order derivative spectra reveal the individual generation of photodichroism of non-aggregated and aggregated species of a liquid-crystalline azo-polymer.

Speciation and quantification of sulfur compounds in petroleum asphaltenes by derivative XANES spectra

The XANES spectrum is employed to study the sulfur functional groups in asphaltenes. Since the asphaltenes are complicated mixture, it is difficult to distinguish different classes of sulfur compounds in asphaltenes. Therefore, the higher order derivative spectra of sulfur XANES were introduced in order to improve sulfur XANES resolution and to qualitatively analysis sulfur functional groups in asphaltenes. Sulfur XANES spectra were deconvoluted by using of several Gaussian and arctangent functions to quantify the sulfur species. In order to convert peak area percentages to atomic percentages, the relative 1s→3p transition probabilities of different sulfur classes must be considered. The areas of the different Gaussian peaks were calculated and revised for their oxidation state-dependent absorption cross-section. The contribution of sulfur species to total sulfur was calculated by the corrected peak areas. The result showed that sulfur species in asphaltenes of atmospheric and vacuum residue were mainly in form of thiophene, sulfoxide, thiophene sulfone and sulfate, while hardly contained sulfide.

Applications of simultaneous equation method and derivative method for the determination of rabeprazole sodium and levosulpiride in pharmaceutical dosage form and dissolution samples

Two simple, accurate, precise, economical procedures, entailing neither irksome sample treatment nor tedious extraction process have been developed for the simultaneous estimation of rabeprazole sodium and levosulpiride in combined tablet dosage form. The first method was based on employing simultaneous equation method for analysis of both drugs. Rabeprazole sodium and levosulpiride have shown absorbance maxima at 284 and 232nm in methanol, respectively. The second method was based on derivative spectrophotometric method involving the determination of both the drugs at their respective zero crossing point (ZCP). The first order derivative spectrum was obtained in methanol and the determinations were made at 231.2nm (ZCP of levosulpiride) for rabeprazole sodium and 246.2nm (ZCP of rabeprazole sodium) for levosulpiride. The linearity was obeyed in the concentration range of 1-20μg/ml for both drugs. The medium of dissolution was used 900ml of phosphate buffer pH 7.4 using a USP type 2 apparatus at a stirring rate of 100rpm. The drug release was evaluated by developed spectroscopic methods. The suitability of the developed method for quantitative determination of rabeprazole sodium and levosulpiride was proved by validation.

Highly sensitive spectrophotometric methods for the determination, validation and thermogravimetric analysis of antiulcer drugs, nizatidine and ranitidine in pure and pharmaceutical preparations

Two sensitive, simple and rapid UV and second order derivative spectrophotometric methods were developed for the determination of nizatidine and ranitidine hydrochloride in pure form and pharmaceutical preparations. For the first method, UV spectrophotometic method, nizatidine was determined at 325 nm and ranitidine at 325.5 nm with detection limits of 0.07 and 0.04 μg/mL, respectively. For the second method, the distances between two extremum values (peak-to-peak amplitudes), 328/356.5 nm for nizatidine and 326/357 nm for ranitidine were measured in the second order derivative-spectra. The detection limits were found to be 0.02 μg/mL for nizatidine and 0.016 μg/mL for ranitidine, respectively. The thermal analysis of the two drugs was studied by Thermogravimetric Analysis-Differential Scanning Calorimetry (TGA-DSC) techniques. Enthalpy changes were obtained 121.9 and 124.15 J/g for nizatidine and ranitidine, respectively. The proposed method was successfully applied to the analysis of pharmaceutical preparations. The results were in good agreement with those obtained using the reference method; no significant difference were found in the accuracy and precision as revealed by the accepted values of t- and F-tests.

ANALYTICAL METHOD DEVELOPMENT OF REPAGLINIDE IN BULK AND SINGLE COMPONENT FORMULATION

Two simple, precise and economical UV method s have been developed for the estimation of Repaglinide in bulk and pharmaceutical formulation Repaglinide absorbance maxima in the zero order derivative spectra wa s 293nm (Method A) and abs orbance maxima in first order derivative spectra wa s 245nm (Method B). Drug followed the Beer - Lambert’s law in the concentration range of 10 - 80µg/ml in method A and 10 - 70µg/ml for method B. Results of the analys is were validated statistically, by recovery studies and were found to be satisfactory.

Highly Sensitive Spectrophotometric Methods for the Determination, Validation and Thermogravimetric Analysis of Antiulcer Drugs, Nizatidine and Ranitidine in Pure and Pharmaceutical Preparations

Two sensitive, simple and rapid UV and second order derivative spectrophotometric methods were developed for the determination of nizatidine and ranitidine hydrochloride in pure form and pharmaceutical preparations. For the first method, UV spectrophotometic method, nizatidine was determined at 325 nm and ranitidine at 325.5 nm with detection limits of 0.07 and 0.04 µg/mL, respectively. For the second method, the distances between two extremum values (peak-to-peak amplitudes), 328/356.5 nm for nizatidine and 326/357 nm for ranitidine were measured in the second order derivative-spectra. The detection limits were found to be 0.02 µg/mL for nizatidine and 0.016 µg/mL for ranitidine, respectively. The thermal analysis of the two drugs was studied by Thermogravimetric Analysis-Differential Scanning Calorimetry (TGA-DSC) techniques. Enthalpy changes were obtained 121.9 and 124.15 J/g for nizatidine and ranitidine, respectively. The proposed method was successfully applied to the analysis of pharmaceutical preparations. The results were in good agreement with those obtained using the reference method; no significant difference were found in the accuracy and precision as revealed by the accepted values of t- and F-tests.

Simultaneous Determination of Prasugrel and Aspirin by Second Order and Ratio First Order Derivative Ultraviolet Spectrophotometry

Two simple, accurate, and precise UV derivative spectrophotometric methods for the simultaneous determination of Prasugrel and Aspirin in synthetic mixture form have been developed. The first method involves measurement of second order derivative spectra of Prasugrel and Aspirin. The zero crossing wavelengths 267.62 nm and 252.40 nm were selected for estimation of Prasugrel and Aspirin, respectively. In the second method, the first order derivatives of ratio spectra were calculated and used for the determination of Prasugrel and Aspirin by measuring the peak intensity at 268 nm and 290 nm, respectively. The methods were validated as per the ICH guideline Q2 (R1). Beer’s law is followed in the range of 5–45 μg/mL for Prasugrel and 25–150 μg/mL for Aspirin by second order derivative method and 6–22 μg/mL for Prasugrel and 45–165 μg/mL for Aspirin by ratio first order derivative method. The recovery studies confirmed the accuracy of the methods. Relative standard deviations for repeatability and inter- and intraday assays were less than 2%. Hence, the described derivative spectrophotometric methods are simple, accurate, precise, and excellent alternatives to sophisticated chromatographic techniques and can be potentially used for the simultaneous determination of Prasugrel and Aspirin in combined dosage form.

Photodegradation processes in two-dyes systems – Simultaneous analysis by first-order spectra derivative method

Wastewaters from textile industry contain a mixture of dyes with other organic and inorganic compounds. The paper proposes a new method of analysis of dyes in real wastewater than global standard parameters used for wastewaters characterisation. The first order derivative spectra method – as a multivariable calibration method – was developed to overcome the spectral overlapping, for the simultaneous analysis of two dyes in solutions. The photodegradation of Bemacid Gelb (BG), Bemacid Rot (BR) and Bemacid Blau (BB) by titanium dioxide films in two-dyes solutions (BG–BR, BG–BB, BR–BB) was investigated and the residual concentration was evaluated based on the first order derivative spectra method. The proposed method is characterised by accuracy for all the dyes (standard deviation of ±3%). The method does not involve expensive instrumentation and dyes separation. The method can be applied to determine any dye present in a binary mixture.

Derivative spectrophotometric method for estimation of antiretroviral drugs in fixed dose combinations.

Lamivudine is cytosine and zidovudine is cytidine and is used as an antiretroviral agents. Both drugs are available in tablet dosage forms with a dose of 150 mg for LAM and 300 mg ZID respectively. The method employed is based on first order derivative spectroscopy. Wavelengths 279 nm and 300 nm were selected for the estimation of the Lamovudine and Zidovudine respectively by taking the first order derivative spectra. The conc. of both drugs was determined by proposed method. The results of analysis have been validated statistically and by recovery studies as per ICH guidelines. Both the drugs obey Beer's law in the concentration range 10-50 μg mL-1,for LAM and ZID; with regression 0.9998 and 0.9999, intercept - 0.0677 and - 0.0043 and slope 0.0457 and 0.0391 for LAM and ZID, respectively.The accuracy and reproducibility results are close to 100% with 2% RSD. A simple, accurate, precise, sensitive and economical procedures for simultaneous estimation of Lamovudine and Zidovudine in tablet dosage form have been developed.

Development and validation of Spectrophotometric method and TLC Densitometric Determination of Irinotecan HCl in pharmaceutical dosage forms

The study is focused to develop and validate a UV-Spectrophotometric and Densitometry method for simultaneous estimation of Irinotecan from their dosage form. Based on spectrophotometric characteristic of method are described for the simultaneous determination of Irinotecan HCl, at 247nm for simple UV spectrum and at 268nm for derivative spectrum was found adequate for quantification. The method was validated for linearity, accuracy, precision, reproducibility, and specificity as per International Conference on Harmonization guidelines. The linearity signal and concentration of Irinotecan in the range of 2–10μg/ml in aqueous solution present a correlation coefficient (r2) of 0.9999 for simple UV and 0.9997 for first order derivative spectrum. Second method is the high performance thin layer chromatographic (HPTLC) separation followed by densitometric measurements on normal phase silica gel 60F254. The chromatographic separation was carried out on precoated silica gel 60F254 aluminium plates using a mixture of toluene/ethyl acetate/methanol/carbon tetrachloride, in the volume ratio of 9.2:5:0.9:0.8 (v/v/v/v) respectively as mobile phase. Densitometric analysis was carried out at 317nm. The linear regression analysis data showed good linear relationship in the concentration range of 200–1200 (ng/band) for Irinotecan. The limits of quantitation for Irinotecan were 34 (ng/band). The limit of detection (LOD) and limit of quantitation (LOQ) were 36 and 57ng/spot, respectively. The drug was satisfactorily resolved with Rf value 0.34±0.08. The accuracy and repeatability of the proposed method were ascertained by evaluating various validation parameters like linearity (200–1200ng/spot). The method was found to be rapid, specific, precise and accurate and can be successfully applied for the routine analysis of Irinotecan bulk and marketed dosage form.

DEVELOPMENT AND VALIDATION OF FIRST ORDER DERIVATIVE SPECTROPHOTOMETRIC METHOD FOR SIMULTANEOUS ESTIMATION DICLOXACILLIN AND CEFDOXIME PROXETIL IN TABLET DOSAGE FORM

The present manuscript describe simple, sensitive, rapid, accurate, precise and economical first derivative spectrophotometric method for the simultaneous determination of dicloxacillin and cefdoxime proxetil in combined tablet dosage form. The derivative spectrophotometric method was based on the determination of both the drugs at their respective zero crossing point (ZCP). The first order derivative spectra was obtained in methanol and the determinations were made at 233.8 nm (ZCP of cefdoxime proxetil) for dicloxacillin and 321 nm (ZCP of dicloxacillin) for cefdoxime proxetil. The linearity was obtained in the concentration range of 10-80 μg/ml for dicloxacillin and 4-32 μg/ml for cefdoxime proxetil. The mean recovery was 100.70 ± 0.38 and 99.90 ± 0.36 for dicloxacillin and cefdoxime proxetil, respectively. The method was found to be simple, sensitive, accurate and precise and was applicable for the simultaneous determination of dicloxacillin and cefdoxime proxetil in pharmaceutical tablet dosage form. The results of analysis have been validated statistically and by recovery studies.

Spectrophotometric Methods for the Estimation of Isoxsuprine Hydrochloride in Bulk and Oral Dosage Form

Four new, simple, sensitive and reproducible spectrophotometric methods have been developed for the estimation of isoxsuprine hydrochloride in tablet dosage form. Method A involves the determination of isoxsuprine hydrochloride by Q-absorbance ratio method at 269nm and 274nm; the Beer's concentration range was found to be 20-100 µg/mL. Method B and Method C involves the determination of isoxsuprine hydrochloride by first derivative spectrophotometry and second derivative spectrophotometry respectively. The normal spectrum was derivatized to first and second order derivative spectrum and the linearity was found to lie within the Beer's range for isoxsuprine hydrochloride. Method D involves the determination of isoxsuprine hydrochloride by Area under curve method (AUC) and the linearity was established. The correlation coefficient for all the four methods were found to be 0.999 and the developed methods were analyzed for specificity, limit of detection (LOD), limit of quantification (LOQ), linearity of response, precision and accuracy. Thus the proposed methods could be adopted for routine analysis of bulk drug and its formulation. Keywords: Area under curve (AUC), Beer's law, Derivative Spectrophotometry, Isoxsuprine hydrochloride, Q-Absorbance ratio

Simultaneous determination of amoxicillin and potassium clavulanate antibiotics in pharmacueutical sample using derivative spectrophotometric method

Derivatives spectrophotometric techniques were developed for the determination of Amoxicillin Trihydrate (Amox) with Potassium Clavulanate (PC) antibiotic binary mixtures. The simultaneous determination of these compounds was accomplished by derivative (1D, 2D and 3D) spectrophotometric technique and applying zero-crossing technique used for determination of (Amox) and (PC) in tablets. The second order derivative absorption spectra at valley λ=299 nm were used for (Amox) and also the second order derivative spectra at peak λ=239.5 nm were used for (PC). No interferences were found between both determined constituents and those of matrix. A good accuracy and precision of simultaneous determination of (Amox) and (PC) were confirmed by statistical analysis. The recovery of individual constituents under established conditions is very high and ranges for synthetic standards mixture and tablets from 100.11, 99.33 and 96.98, 96.84 respectively. Linearity is maintained within a wide concentration range from 2.0 to 90.0 μg.mL-1 and from 10.0 to 90.0 μg.mL-1 for (Amox) and (PC) and linearity percentage 99.98 and 99.99 respectively. The detection limit is 0.211 μg.mL-1 for (Amox) and 0.259 μg.mL-1 for (PC). The corresponding quantitation limits are 0.704 μg.mL-1 (Amox) and 0.864 μg.mL-1 for (PC).