Divisor Ratio Spectra Derivative Method Research Articles

Utilizing two different sustainable and green spectrophotometric approaches using derivative ratio spectra for the determination of a ternary severely overlapped mixture: application to veterinary formulation

Mathematical manipulation technique has proven to be a very powerful tool for efficient processing and handling of highly overlapped spectra. This work introduced two green and sustainable approaches for the successful recovery of the ternary mixture, Tylosin tartarate (TYL), Sulfadimdine (SLD), and Trimethoprim (TRI). The approaches were constructed using three different methods, derivative ratio spectrum zero-crossing method (DRSZ), double divisor ratio spectra derivative method (DDRD), and factorized derivative ratio method coupled with spectrum subtraction (FDRM-SS). The two approaches succeeded in recovering the three drugs (Linearity range achieved were 0.5–5 µg/mL for TYL, 0.3–1.3 µg/mL for SLD, and 0.3–5 µg/mL for TRI), giving convenient standard deviations and satisfactory recovery percentages. The recommended methods have been verified in accordance with (ICH) guidelines. When the results were statistically compared to the official methods, no significant difference was found. Both AGREE—Analytical GREEnness Metric Approach and Software, and White Analytical Chemistry (WAC) RGB model gave scores of 0.93 and 97.2%, respectively, which proved that the approaches were eco-friendly and abiding by the sustainability principles.

Simultaneously Estimation of Multicomponent Containing Formulation by using UV-Spectroscopy [Aspirin-Atorvastatin

The market is currently offering a wide range of combination dose forms, and the quantity is growing daily. Due to their improved potency, various actions, speedier relief, fewer side effects, and higher patient acceptability, these multicomponent formulations are becoming more and more popular. It is therefore intended that these formulations satisfy all requirements for their efficacy, safety, and quality. This is only feasible if many analytical methods are available to determine them. When doing a simultaneous multicomponent analysis, various UV spectrophotometric techniques are applied.These techniques rely on logging and processing absorption spectra computationally. The various techniques covered in this review include the use of simultaneous equations, derivative spectrophotometry, mean centring of the ratio spectra, absorption factor method, double divisor ratio spectra derivative method, successive ratio derivative spectra, Q-absorbance ratio method, isosbestic point method, absorpitivity factor method, dual wavelength method, mean centring of the ratio spectra, and multivariate methods. A synopsis of the theories and a few uses for these techniques are given.

A new selective colorimetric method coupled with a high-resolution UV method for the consecutive quantification of three drugs in semi-solid preparations

Triderm® cream and ointment contain clotrimazole (CLO), betamethasone dipropionate (BET), and the poor UV absorbing gentamycin (GEN), in addition to the preservative benzyl alcohol (BEN) which exists only in a cream preparation. A green, selective colorimetric approach was elaborated to increase the sensitivity of GEN quantification in Triderm® preparations, which depends on the immediate formation of a pink ion-pair between GEN and erythrosine (ERY) reagent in an aqueous acidic medium. The ion pair was made soluble in water with the assistance of the surfactant agent poloxamer 188 which is presented in this manuscript as an efficient solubilizing agent for the hydrophobic ion-pair. This surfactant agent has the feature of not affecting the native color of ERY, additionally the ease of preparing its aqueous solution with no need for heating or long waiting. The resulting complex GEN-ERY was measured directly at 545nm. This colorimetric approach was coupled with the Unlimited Derivative Ratio (UDD), which is a new smart UV method employed for the concurrent quantification of BET and CLO in Triderm® preparations without any intervention from BEN, due to its capability to resolve an extremely overlapped ternary spectrum that has no extended part, iso-absorptive point or robust zero crossing point. The newly developed UDD method depends on filtrating and measuring the signal of BET and CLO through calculating the equality factor(F) for CLO and BET after dividing their spectrum by BEN spectrum, derivatizing the resulting ratio spectrum, then constructing a regression equation employing the F factor for each BET and CLO. The overlapping excipient BEN was quantified via the Double Divisor Ratio spectra derivative method (DDR) relying on using a divisor comprising of a mix of BET + CLO. The advanced spectrophotometric approach validity was checked by confirming the linearity, accuracy, precision, and specificity in accordance with the ICH directions. NO notable difference when statistically comparing the newly established approach to the reference approach.

NOVEL SPECTROPHOTOMETRIC METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION OF ABACAVIR SULPHATE, LAMIVUDINE AND DOLUTEGRAVIR SODIUM IN DOSAGE FORM

Double Divisor ratio spectra derivative method was developed and validated for a ternary mixture containing abacavir sulphate (ABA), lamivudine (LAM) and dolutegravir sodium (DOL) in distilled water. The method is based on dividing the absorption spectra of ternary mixture by the sum of absorption spectra of two of the three components and then taking the first derivative of the ratio spectra. The linear range was found to be 5 – 40 µg mL-1 for ABA, 4 – 20 µg mL-1 for LAM and 1 - 20 µg mL-1 for DOL. The mean % recoveries were found to be in the range of 98.85 – 100.93 % for ABA, 99.65 – 99.38 % for LAM and 100.29 – 98.67 % for DOL. ICH guidelines were used to validate the developed method. The proposed method can be successfully applied to pharmaceutical formulations as it is rapid, simple, sensitive, selective and accurate.

APPLICATION OF TWO ADVANCED DERIVATIVE SPECTROPHOTOMETRIC METHODS FOR SIMULTANEOUS ESTIMATION OF SALBUTAMOL SULPHATE, AMBROXOL HYDROCHLORIDE AND THEOPHYLLINE IN PURE AND COMMERCIAL FORMULATIONS

Objective: Two advanced spectrophotometric methods have been proposed for the simultaneous determination of Salbutamol sulphate, Ambroxol hydrochloride and Theophylline in pure and pharmaceutical formulations. The proposed methods exclude the hectic steps of time-consuming sample preparations or purification or separation steps. There is no any spectrophotometric method has been avail for simultaneous estimation of the ternary mixture containing Salbutamol sulphate, Ambroxol hydrochloride and Theophylline.
 Methods: The methods are derivative ratio spectra zero-crossing method and double divisor ratio spectra derivative method respectively. Both the methods are found to be rapid, accurate, precise, reliable and economical as well. The developed methods show best results in terms of linearity, accuracy, precision, limit of detection and limit of quantification for standard laboratory mixtures of pure drugs and marketed formulations.
 Results: The range for Salbutamol sulphate, Ambroxol hydrochloride and Theophyllineare found to be 1-35 µg ml-1, 5-35 µg ml-1and 6-60 µg ml-1 respectively. For the derivative ratio spectra zero-crossing method, the values of the limit of detection are found to be 0.3161 µg ml-1, 0.2212 µg ml-1 and 0.2910 µg ml-1 and the values limit of quantification are found to be 0.9571 µg ml-1, 0.7412 µg ml-1 and 0.9671 µg ml-1 for Salbutamol sulphate, Ambroxol hydrochloride and Theophylline respectively. For double divisor ratio spectra derivative method, limit of detection values is found to be 0.3251 µg ml-1, 0.2591 µg ml-1 and 0.2640 µg ml-1 and the limit of quantification values are found to be 0.9870 µg ml-1, 0.8650 µg ml-1 and 0.8812 µg ml-1 for Salbutamol sulphate, Ambroxol hydrochloride and Theophylline respectively.
 Conclusion: The common excipients and additives did not interfere in the determinations of any of the drugs while being analysed for commercial formulations. These two spectrophotometric methods, which determine SS, AH, and THE simultaneously, are simple, specific, accurate, precise, rapidly, and economically, indicating that they can be used routinely in pharmaceutical analysis. As a result, derivative spectrophotometry may be used effectively for the simultaneous determination of SS, AH and THE in the combined dosage forms without any prior separation of individual drugs.

Resolving Problems Encountered in Spectrophotometric Analysis of a Ternary Mixture of Linagliptin, Empagliflozin, and Metformin Hydrochloride

There are two main problems encountered in spectrophotometric analysis of a ternary mixture composed of linagliptin LINA, empagliflozin EMPA and metformin hydrochloride MET. The first problem is due to the severe overlap in their zero and derivative spectra. To overcome this problem, LINA was determined by direct spectrophotometry at λ max = 298 nm where there is no interference from other components while, EMPA and MET were determined using double divisor ratio spectra derivative method DDRD. In this method, the first derivative spectra were calculated for ratio spectra generated by dividing the absorption spectra of ternary mixtures containing increasing concentrations of one of the components by a standard spectrum of binary mixture of the other two components (double divisor). The calibration graphs were constructed by measuring the amplitude at either the minimum or maximum wavelengths against the concentrations. The selected wavelengths for determination of EMPA and MET are 282.92 and 250 nm, respectively. The second problem arises from the presence of LINA and EMPA as minor components in their recently approved dosage form with MET thus, sample enrichment through spiking was employed for LINA and EMPA to enable their spectrophotometric analysis in laboratory prepared mixtures that have the same ratio of the three components as in their pharmaceutical dosage form.

Smart spectrophotometric methods for stability assessment of two co-formulated antigout drugs

Simple, sensitive and accurate stability indicating spectrophotometric methods have been developed for the simultaneous determination of probenecid, colchicine as well as colchicine degradation product in their ternary mixture. Probenecid was firstly assayed using the double divisor ratio spectra derivative method. On the other hand, three spectrophotometric methods, namely: ratio difference, derivative ratio and mean centering of ratio spectra, have been suggested for the simultaneous quantification of colchicine and its degradation product. The obtained calibration curves were linear at 2.5–30.0 μg/mL, 0.5–25.0 μg/mL and 1.0–13.0 μg/mL for probenecid, colchicine and colchicine degradation product, respectively. The investigated methods were validated in accordance with the International Council for Harmonisation guidelines and were effectively used for quantification of probenecid and colchicine in their bulk powders and combined pharmaceutical dosage form.

A Double Divisor Ratio-Spectra Derivative Method for the Ternary Mixture of Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium

Quantitative analysis of formulation containing Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium were performed using double divisor ratio spectra derivative method. Detection wavelength for Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium was 240.2 nm, 231.8 nm and 263.2 nm respectively. The linearity range for all three drugs was 2-20 μg/mL and it was validated through regression analysis and residual analysis. Mean percentage recovery was 100.09 %, 100.60 % and 99.86 % for Aspirin, Clopidogrel Bisulphate and Rosuvastatin Calcium respectively. The developed method was validated according to International Council for Harmonization guidelines and validation approach is much more justified than the usual approach. The use of advanced statistical tools for validation ensures the efficiency; quality and reproducibility of our method. Obtained results were satisfactory and ensured the quality and reproducibility of the method.

Immobilized Nano-TiO2 Photocatalysts for the Degradation of Three Organic Dyes in Single and Multi-Dye Solutions

Heterogeneous photocatalysis with titanium dioxide (TiO2) is considered one of the most promising Advanced Oxidation Processes (AOPs). In order to solve issues related to catalyst recovery and possible agglomeration, which are typical of catalysts in nanoparticle form, self-organized nanotubular TiO2 films directly immobilized on a metal substrate can be produced through anodization. In this study, a nanotubular anodic oxide was tested in the degradation of three organic dyes, namely Direct Red 80, Methylene Blue, and Rhodamine B, in single, binary, and ternary mixtures, to simulate industrial effluents with the co-presence of multiple dyes. To better understand the dyes’ behavior and possible interaction effects, spectrophotometry was used to analyze the degradation of each dye in the mixture. The zero-crossing first-order derivative approach and double divisor ratio spectra derivative method were used for the analysis of binary and ternary mixtures, respectively, to overcome quantification problems due to spectra overlapping. The photocatalytic system demonstrated good efficiency, supporting the use of nanotubular TiO2 as a photocatalyst for dye mixtures. Moreover, the interaction among dyes can actually affect, both positively and negatively, photodegradation kinetics, posing an issue in understanding the actual efficiency of the purification process as a function of the effluent composition.

DERIVATIVE UV SPECTROSCOPIC APPROACHES IN MULTICOMPONENT ANALYSIS–A REVIEW

The spectrophotometric multi-component analysis involves spectrum recording and mathematical equations. However, spectral interference poses a major limitation when mixture samples are encountered. To overcome this derivative spectrophotometry (DS) has been introduced for the resolution of overlapping peaks.
 In this review modified methods like derivative quotient spectra, double divisor ratio spectra derivative method, double divisor means centering of ratio spectra method, derivative subtraction coupled with the constant multiplication method (DS-CM), amplitude subtraction (AS), modified amplitude subtraction (MAS), amplitude factor method (P-Factor), amplitude modulation method (AM), amplitude summation method (A-Sum), simultaneous derivative ratio spectrophotometry (S1DD), derivative compensation ratio via regression equation, differential dual wavelength (D1 DWL), differential derivative ratio (D1DR), successive derivative subtraction method (SDS) and derivative transformation (DT) of derivative spectrophotometry theories and applications are reviewed.
 These methods were applied to solve different complex pharmaceuticals mixtures. These developed methods were simple and cost-effective.

TiO2–active carbon composites for wastewater photocatalysis

Titanium oxide–active carbon composites (TiO2–AC) with photocatalytic activity were prepared by sol–gel method at low temperature. Titanium isopropoxide and active carbon were used as precursors, ethanol as solvent and HNO3 as catalyst. The composition of the studied composites was accomplished by means of X-ray diffraction, and Fourier Transform-Infrared spectrometry. The rutile crystalline phase was present in all samples. In scanning electron microscopy images the TiO2 aggregates existed either on the surface of the active carbon or heterogeneously dispersed over the whole catalyst matrix. The contact angle and point of zero charge measurements were applied to characterise the surface energy and surface charge. The photocatalytic activities of the TiO2–AC composites were evaluated in the bleaching of methyl orange and methylene blue solution from ternary mixture of methyl orange, methylene blue and Triton X100. The double divisor ratio spectra derivative method (as a multivariable calibration method) was developed to overcome the spectral overlapping, for the simultaneous analysis of ternary mixture.

Simultaneous Estimation and Statistical Evaluation of Developed Validated Methods for Combined Drugs in Marketed Formulation

We have developed rapid derivative methods for simultaneous estimation of paracetamol (PCM), chlorpheniramine maleate (CPM), and phenylephrine hydrochloride (PH) in pure and liquid dosage form. All methods are simple, accurate, rapid, precise, economical and reliable. Methods are third derivative zero crossing spectrophotometry (I), single divisor ratio spectra derivative spectrophotometry (II), double divisor ratio spectra derivative method (III) and Vierdot's method (IV). All the method utilizes methanol: 0.1N hydrochloric acid (1:9). For method I, II, III and IV Limit of Detection (L.O.D.) values were within 0.59-1.37 μg/mL, 0.60 - 3.72 μg/mL and 0.71- 3.22 μg/mL respectively; and Limit of Quantification (L.O.Q.) values were within 1.83- 4.40 μg/mL, 2.11-11.91 μg/mL and 2.32-10.70 μg/mL for PCM, CPM and PH respectively. The linearity ranges for PCM, CPM and PH were found to be 1.5-15μg/mL, 5-40 μg/mL and 9-64 μg/mL respectively, showing regression coefficient values 0.999 < R 2 < 1. Precision values were found less than 2% Relative Standard Deviation (R.S.D.) for all methods. The results obtained have been compared statistically via analysis of variance (ANOVA).

The Spectrophotometric Multicomponent Analysis of a Ternary Mixture of Paracetamol, Aspirin, and Caffeine by the Double Divisor-Ratio Spectra Derivative Method

Double divisor-ratio spectra derivative method based on the spectrophotometric data was developed for the simultaneous analysis of a ternary mixture containing paracetamol, aspirin, and caffeine, without prior separation. This method is based on the use of the derivative of the ratio spectrum obtained by dividing the absorption spectrum of the ternary mixture by a standard spectrum of a mixture of two of the three compounds in the title mixture. The concentrations of three compounds in their mixture are determined by using their respective calibration graphs which are obtained by measuring the amplitude at either the maximum or minimum wavelengths selected. The selected wavelengths for determination of aspirin, caffeine, and paracetamol are 241.5, 256, and 258.5 nm, respectively. All of the solutions adjusted to pH 11 before recording the spectra in the range of 220 to 320 nm. Also, the mathematical explanation of the procedure is illustrated. The method was applied for the assay of Excedrin containing paracetamol, aspirin, and caffeine.

The Spectrophotometric Multicomponent Analysis of a Ternary Mixture of Ibuprofen, Caffeine and Paracetamol by the Combination of Double Divisor-Ratio Spectra Derivative and H-Point Standard Addition Method

A new spectrophotometric method was developed for the simultaneous analysis of a ternary mixture containing paracetamol (PAR), ibuprofen (IBU) and caffeine (CAF) without prior separation. H-point standard addition method (HPSAM) was used for the first time in the analysis of a component (IBU) in a ternary mixture (paracetamol, ibuprofen and caffeine). In contrast, PAR and CAF determined using double divisor ratio spectra derivative method. This method is based on the use of derivative of the ratio spectrum obtained by dividing the absorption spectrum of the ternary mixture by a standard spectrum of a mixture of two of the three compounds in the title mixture. The concentrations of PAR and CAF compounds in their mixture are determined by using their respective standard addition graphs which are obtained by measuring the amplitude at either the maximum or minimum wavelengths selected. The mathematical explanation of the procedure is illustrated. It was shown that at wavelengths 226 and 260 nm, the coordinate of H-point is only dependent on the concentration of IBU without any interference by PAR and CAF. This method was successfully applied for the analysis of Novafen capsule, with no interference from excipients as indicated by the recovery study results. The proposed method is simple and rapid and can be easily used in the quality control of drugs as an alternative analysis tools.

Application of Fourier Function to Double Divisor Ratio Spectra Curves for Analysis of Some Amoebicide Drugs in Their Ternary Mixtures

This work concerns with development of spectrophotometric methods for analysis of Metronidazole, Diloxanide Furoate and Mebeverine HCl. Method (I) is double divisor ratio spectra derivative method (DDRD) which depends on using derivative signals of the ratio spectra using double divisor. Method (II) is hybrid double divisor ratio spectra (HDDR) which depends on convolution of the double divisor ratio spectra using trigonometric Fourier functions. The developed HDDR method showed better selectivity than DDRD due to its higher resolution power. The methods have been applied for analysis of the studied drugs in their commercial tablets and the results obtained from the analysis of the market sample by the proposed methods were statistically compared with those obtained by manufacturer RP-HPLC method.

SIMULTANEOUS DETERMINATION OF AMBROXOL, GUAIPHENESIN AND LEVOSALBUTAMOL SULPHATE IN PHARMACEUTICAL FORMULATIONS WITH THE USE OF FOUR RAPID DERIVATIVE SPECTROPHOTOMETRIC METHODS

Four simple, rapid, accurate, precise, reliable and economical spectrophotometric methods have been proposed for simultaneous determination of ambroxol, guaiphenesin and levosalbutamol sulphate, in pure and pharmaceutical formulations without any prior separation or purification step. The methods are first derivative zero crossing spectrophotometry, simultaneous equation, derivative ratio spectra zero crossing and double divisor ratio spectra derivative method. Developed methods show best results in terms of linearity, accuracy, precision, LOD and LOQ for standard laboratory mixtures of pure drugs and marketed formulations. Common excipients and additives did not interfere in determinations of these APIs. Results obtained by the proposed methods have been statistically compared by means of student t-test.

Simultaneous Determination of a Ternary Mixture of Doxylamine Succinate, Pyridoxine Hydrochloride, and Folic Acid by the Ratio SpectraZero-Crossing, Double DivisorRatio Spectra Derivative, and Column High-Performance Liquid Chromatographic Methods

Three simple, rapid, and accurate methods, i.e., the derivative ratio spectra-zero-crossing method (method I), double divisor-ratio spectra derivative method (method II), and column reversed-phase high-performance liquid chromatographic (RP-HPLC) method (method III) were developed for the simultaneous determination of doxylamine succinate (DOX), pyridoxine hydrochloride (PYR), and folic acid (FA) in their ternary mixtures and in tablets. In methods I and II, the calibration graphs were linear in the range of 2.5-80, 1.0-40, and 1.0-30 microg/mL for DOX, PYR, and FA, respectively. In the HPLC method, the separation of these compounds was performed using mobile phase consisting of 0.05 M phosphate buffer (pH 6.3)-methanol-acetonitrile (50 + 20 + 30, v/v/v), and UV detection was performed at 263 nm. Linearity was observed between the concentrations of the analytes and peak areas [correlation coefficient (r) > or =0.9998] in the concentration range of 1.0-200, 4.0-600, and 4.0-600 microg/mL for DOX, PYR, and FA, respectively. The standard deviation of retention time in method III was 0.011, 0.015, and 0.016 for DOX, PYR, and FA, respectively. The precision studies for all of the methods gave relative standard deviation values of <2%. The results obtained from the methods were statistically compared by means of Student's t-test and the variance ratio F-test. It was concluded that all of the developed methods were equally accurate, sensitive, and precise. These methods could be applied to determine DOX, PYR, and FA in their combined dosage forms.

A new hybrid double divisor ratio spectra method for the analysis of ternary mixtures

A new spectrophotometric method was developed for the simultaneous determination of ternary mixtures, without prior separation steps. This method is based on convolution of the double divisor ratio spectra, obtained by dividing the absorption spectrum of the ternary mixture by a standard spectrum of two of the three compounds in the mixture, using combined trigonometric Fourier functions. The magnitude of the Fourier function coefficients, at either maximum or minimum points, is related to the concentration of each drug in the mixture. The mathematical explanation of the procedure is illustrated. The method was applied for the assay of a model mixture consisting of isoniazid (ISN), rifampicin (RIF) and pyrazinamide (PYZ) in synthetic mixtures, commercial tablets and human urine samples. The developed method was compared with the double divisor ratio spectra derivative method (DDRD) and derivative ratio spectra-zero-crossing method (DRSZ). Linearity, validation, accuracy, precision, limits of detection, limits of quantitation, and other aspects of analytical validation are included in the text.

Simultaneous determination of salbutamol sulphate, bromhexine hydrochloride and etofylline in pharmaceutical formulations with the use of four rapid derivative spectrophotometric methods

Four simple, rapid, accurate, precise, reliable and economical spectrophotometric methods have been proposed for simultaneous determination of salbutamol sulphate (SS), bromhexine hydrochloride (BH) and etofylline (ET) in pure and commercial formulations without any prior separation or purification. They were first derivative zero crossing spectrophotometry (method 1), simultaneous equation method (method 2), derivative ratio spectra zero crossing method (method 3) and double divisor ratio spectra derivative method (method 4). The ranges for SS, BH and ET were found to be 1–35 μg mL −1, 4–40 μg mL −1 and 5–80 μg mL −1. For methods 1 and 2, the values of limit of detection (LOD) were 0.2314 μg mL −1, 0.4865 μg mL −1 and 0.2766 μg mL −1 and the values of limit of quantitation (LOQ) were 0.7712 μg mL −1, 1.6217 μg mL −1 and 0.9221 μg mL −1 for SS, BH and ET, respectively. For method 3, LOD values were 0.3297 μg mL −1, 0.2784 μg mL −1 and 0.7906 μg mL −1 and LOQ values were 0.9325 μg mL −1, 0.9282 μg mL −1 and 2.6352 μg mL −1 for SS, BH and ET, respectively. For method 4, LOD values were 0.3161 μg mL −1, 0.2495 μg mL −1 and 0.2064 μg mL −1 and LOQ values were 0.9869 μg mL −1, 0.8317 μg mL −1 and 0.6879 μg mL −1 for SS, BH and ET. The precision values were less then 2% R.S.D. for all four methods. The common excipients and additives did not interfere in their determinations. The results obtained by the proposed methods have been statistically compared by means of Student t-test and by the variance ratio F-test.

Content uniformity and dissolution tests of triplicate mixtures by a double divisor-ratio spectra derivative method

The use of a UV double divisor-ratio spectra derivative calibration for the simultaneous analysis of synthetic samples and commercial tablet preparations without prior separation is proposed. The method was successfully applied to quantify three ternary mixtures, chlorpheniramine maleate and caffeine combined with paracetamol or acetylsalicylic acid and a mixture of acetylsalicylic acid combined with paracetamol and caffeine, using the information in the absorption spectra of appropriate solutions. Beer's law was obeyed in the concentration range of 0.84–4.21 μg/ml for chlorpheniramine maleate, 1.60–15.96 μg/ml for caffeine, 2.0–20.0 μg/ml for acetylsalicylic acid and 1.58–15.93 μg/ml for paracetamol. The whole procedure was applied to synthetic mixtures of pure drugs as well as to commercial preparations (Algon®) by using content uniformity and dissolution tests (USP 24) and was found to be precise and reproducible. According to the dissolution profile test more than 84% of paracetamol and caffeine were dissolved within 20 min. Acetylsalicylic acid dissolved more slowly, taking about 45–60 min to dissolve completely. A chemometric method partial least squares (PLS) and a HPLC method were also employed to evaluate the same mixtures. The results of the proposed method were in excellent agreement with those obtained from PLS and HPLC methods and can be satisfactorily used for routine analysis of multicomponent dosage forms.