INTRODUCTION:

There are various analytical methods are used now these days for the estimation. Various Analytical methods like potentiometer, HPLC, aqueous and non-aqueous titrations are used in The field of analysis. Aqueous and non-aqueous titrations are also used in the field of analysis. But now these days HPLC plays an important role in the field of analysis for the quantitative Determination. HPLC is referred as high pressure liquid chromatography which is a Separation technique based on the solid stationary phase and liquid mobile phase. Chromatography is mass transfer process involve adsorption. The active component of the Column is adsorbent which is granular material of solid particles (silica, polymers). The Principle of separation in the normal phase mode and reverse phase mode is adsorption in Which the substances travel/separate according to their relative affinities.

Now these days HPLC plays an important role in the field of pharmaceutical analysis for the separation of various substances from the mixture substance

Parameters for analytical method validation:

· Selectivity and specificity

· Linearity

· Range

· Accuracy

· Precision

· Limit of detection

· Limit of quantitation

· Robustness

· Ruggedness

1. Selectivity and specificity:

· The term selectivity And specificity are Often used interchangeably

· The USP monograph defines selectivity of an analytical method as its Ability to measure accurately an analyte in the presence of Interference, such as synthetic precursors, excipients, enantiomers And known degradation products that may be expected to be present In the matrix

· Selectivity in liquid Chromatography is obtained by choosing optimal Column and setting chromatographic condition, such a mobile phase Composition, column temperature, and detector wavelength

· As per ICH guidelines, specificity is the ability to assess unequivocally The analyte in the presence of components which may be expected to Be present Typicaly, these might include impurities, degredant, matrix etc

2. Linearity:

· The linearity of an analytical procedure is its ability to obtain test results that Are directly proportional to the concentration of the analyte in the sample.

· Linearity is usually demonstrated by the analysis of various concentrations of The analyte (s) across the indented range and represented graphically. “A Statistical analysis of the data is usually required, such as the calculation of a Regression line using the method of least square.A minimum of 5 concentration is required

3. Range:

· Range of the analytical procedure is the interval between the upper And the lower concentration of the analyte for which it has been Demonstrated that the analytical procedure has a suitable precision, Accuracy and linearity.

· For assay the range is usually not less than 80 to 120% of the test Concentration.

· For determination of content uniformity the range is usually not less Than 70 to 130% or the test concentration.

· For determination of impurities the range is usually not less than Reporting limit of the impurity to 120% or the specification.

· For dissolution testing the range is usually ±20% over the expected Concentration

4. Accuracy and precision:

· Accuracy of an analytical procedures expresses the closeness of agreement Between the value which is accepted either as a conventional true value or An accepted reference value and the value found.this is sometimes termed as Trueness

· Precision of an analytical procedures expresses the closeness between a series of measurement obtained from multiple sampling of the same heterogeneous sample under the prescribed condition.

5. Robustness:

· The Robustness of an analytical procedures is the measures of its capacity to remain unaffected by small but variations in the method parameters and provide indications of its realiability during normal usage.

6. Ruggedness:

· Ruggedness is measured of reproducibility test under the variation conditions normally expected from laboratory to laboratory and from analyst to analyst. And chemical to chemical.

· Ruggedness of an analytical method is degree of reproducibility of the test result obtained by the Analysis of the sample under a variety of conditions, such as different laboratories analyst, instrument, reagent, temperature, time.et

Introduction to Drug Profile:

Background of Doxofylline:

Doxofylline is a methylxanthine derivative with the presence of a dioxolane group in position 7. As a drug used in the treatment of asthma, doxofylline has shown similar efficacy to theophylline but with significantly fewer side effects in animal and human studies. In contrast with other xanthine derivatives, doxofylline does not significantly bind to adenosine alpha-1 or alpha-2 receptors and lacks stimulating effects. Decreased affinity for adenosine receptors may account for the better safety profile of doxofylline compared to theophylline 9. Unlike theophylline, doxofylline does not affect calcium influx and does not antagonize the actions of calcium channel blockers which could explain reduced cardiac adverse reactions associated with the drug 5. The anti-asthmatic effects of doxophylline are mediated by other mechanisms, primarily through inhibiting the activities of the phosphodiesterase (PDE) enzyme.

Structure:

IUPAC Name: 7-(1,3-dioxolan-2-ylmethyl)-1,3-dimethylpurine-2,6-dione

Molecular formula: C₁₁H₁₄N₄O₄

Molecular weight: 266.257 g/mol

Category: Bronchodilator

Solubility: Soluble in Trichloromethane, water and acetone, slightly soluble in acetic acid and ethyl alcohol

Melting point 141-144’

Pharmacodynamics:

Doxofylline is a methylxanthine bronchodilator with potent bronchodilator activity comparable to that of theophylline. In animal studies, doxofylline demonstrated to attenuate bronchoconstriction, inflammatory actions and the release of thromboxane A2 (TXA2) when challenged with platelet-activating factor. Doxofylline does not demonstrate direct inhibition of any histone deacetylase (HDAC) enzymes or known PDE enzyme isoforms and did not act as an antagonist at A2 or A2 receptors. The affinity for adenosine A1, A2A and A2B receptors are reported to be all higher than 100 µM. It only displays an inhibitory action against PDE2A1 and antagonism at adenosine A(2A) at high concentrations A study demonstrated that doxofylline interacts with β2-adrenoceptors to induce blood vessel relaxation and airway smooth muscle relaxation. In dog studies, doxofylline decreased airway responsiveness at a dose that did not affect heart rate and respiratory rate.

Reported methods of Doxofylline

Sr.no	Drug Formulation	Methods	Brief introduction	Refference
1	Doxofylline	RP-HPLC	Mobile phase-: acetonitrile, phosphate buffer(50:50%v/v) PH 3 Column HiQsilc18 Flow rate 1ml/min Wavelength 272nm	1
2	Doxofylline and Sertaline	RP-HPLC	Mobilephase-: acetonitrile:water(30:70%v/v) PH 3 Column -: kromosilC18 Flow rate -:1ml/min Wavelength -:234	2
3	Doxofylline	RP-HPLC	Mobile phase-: Acetonitrile: Formic acid(90:10% v/v) Column -:Kromosilc28 Flow rate -:1ml/min Wavelength -:274nm	3
4	Doxofylline and montelukast sodium	RP-HPLC	Mobile phase-:Methanol:Sodium phosphate buffer (75:25 %w/w) Column -:Inertsilc18 Flow rate -:1ml/mi Wavelength -:230nm	4
5	Doxofylline and ambroxol	RP-HPLC	Mobile phase-: Pottasium dihydrogen Ortho phosphate buffer: Acetonitrile (25:75 %w/w) Column -:Kromosilc18 Flow rate -:1ml/min Wavelength -:257nm	5
6	Doxofylline Montelukast Levocetrizine hydrochloride	RP-HPLC and UV Spectroscopy	Mobile phase-: ammonia acetate buffer: Acetonitrile (75:25%v/v Column -:Inertsilc18 Flow rate -:1ml/min Wavelength -:230nm	6
7	Doxofylline and ambroxol	RP HPLC Simultaneous Estimation	Mobile phase-: Pottasium dihydrogen Ortho phosphate buffer: Acetonitrile (25:75%w/w) Column -:Inertsilc18 Flow rate -:0.8ml/min Wavelength -:257 nm Run time-:10 min	7
8	Doxofylline	UV Spectroscopy	Diluent -: Sodium hydroxide and pottasium dihydrogen phosphate PH 7.6	8

REFERENCES:

1. Ashu Mittal, Shikha Parmar. Development and validation of RP-HPLC for determination of Doxofylline in bulk drug and pharmaceutical dosage forms. Journal of Analytical Chemistry. 2010; 65(3): 293-297.

2. B Victoria Rani, C. Parthban, M. Sudhakar. Method development and validation for simultaneous estimation of Sertraline and Doxofylline in pharmaceutical dosage form by RP-HPLC. International Journal of Pharmaceutical Sciences. 7: 465-468.

3. Revathi R, Ethiraj T, Themozhi P, Saravanan VS, Ganesan V. HPLC method development for simultaneous analysis of Doxofylline and Montelukast sodium in combined form, Pharm Methods. 2(4): 223-228.

4. Sonia M. Nappinnai, K. Manikandan. Simultaneous estimation of Doxophylline and Ambroxol in tablet dosage form by RP-HPLC. International Journal of Pharmaceutical Science and Research. 2016; 7(9): 3721-3727.

5. Nitish kumar, Durgadas Anghore, Ravindra K Rawal, Abhay pandey. RP-HPLC and UV method development for simultaneous estimation of Doxofylline, Montelukast and Levocetrizine in pharmaceutical dosage form. Analytical Chemistry Letters, 2018; 8(2):195-204.

6. B. Subhandana, K Sushmita, Buchi N. Nalluri. RP-HPLC-PDA method for the analysis of Terbutaline sulphate in bulk dosage form and in dissolution samples. Journal of Applied Pharmaceutical Sciences. 3(3): 126-132.

7. Porel A, Haty S, Kundu A. Stability indicating HPLC method for simultaneous determination of Terbutaline sulphate, Bromhexine and Guaifenesin, Indian Journal of Pharmaceutical Sciences. 2011; 73(1): 46-56.

8. M. V. Vinod, I, Vasundhara, K. S. Krishnamurthy. RP-HPLC UV method development and validation for simultaneous determination of Terbutaline sulphate, Ambroxol hydrochloride and Guaifenesin in pure and dosage form. Indian Drugs. 2001; 38(8): 428-432.

Received on 15.03.2024 Modified on 03.04.2024

Asian J. Res. Pharm. Sci. 2024; 14(2):189-191.

DOI: 10.52711/2231-5659.2024.00031