INTRODUCTION:

Literature survey tells about the determination of Venlafaxine by using UPLC. In addition, it also tells about the quantification of Venlafaxine with another drug using HPLC and UV spectrophotometers.^1-4 Apart from these some other methods are also available for the determination of Venlafaxine in bulk as well as the dosage form. To achieve the purpose of the current work, we developed a simple spectrophotometric procedure.^5-8

Venlafaxine increases serotonin levels, norepinephrine levels, and dopamine levels in the brain by blocking transport proteins and stopping their reuptake at presynaptic terminals. As a result, more transmitters are available at the synapse, which subsequently stimulates postsynaptic receptors. Serotonin reuptake inhibitors (SNRIs) interact primarily with serotonergic and noradrenergic neurons, while cholinergic and histaminergic receptors are little affected or unaffected by SNRIs. Venlafaxine is a bicyclic phenylethylamine compound⁹. In comparison to norepinephrine reuptake inhibitors, Venlafaxine is a more potent inhibitor of serotonin reuptake. With a dose of 75 mg, Venlafaxine acts primarily as a selective serotonin reuptake inhibitor. The higher the dosage, the greater the effect on the norepinephrine transporter as well¹⁰.

Fig. 1: Structure of Venlafaxine Hcl

MATERIALS AND METHODS:

Materials:

Table No: 1 Materials used in present research work

S. No.	Materials	Source
1.	Venlafaxine Hcl	Akums Drugs and Pharmaceuticals Ltd, Haridwar.
2.	Ethanol	Changshu Hongsheng Fine Chemical Co., Ltd.

Type of Equipment:

Table No: 2 The present research work was conducted using the following equipment

S. No.	Equipment	Source
1.	UV Spectrophotometer	Double Beam Spectrophotometer
2.	Sonicator	Wensar

Methods:

UV Spectrophotometry:

A dual beam UV/VIS spectrophotometer was used to measure the spectral characteristics that cells of 1cm width made of quartz and matched. All chemicals used were of analytical grade. An authentic sample of Venlafaxine Hcl was obtained as a gift sample by Akums Drugs and Pharmaceuticals Ltd, Haridwar.

Method Development:

Solvent selection:

We selected various solvents to determine Venlafaxine Hcl's solubility to select the most suitable solvent. We found Venlafaxine Hcl's solubility was determined to be free in the following solvents: methanol, ethanol. ethanol was selected as solvent.

Determination of λmax of Venlafaxine Hcl:

According to Bansode A.S. and Saravanan K.P., 2019, First Stock solution of venlafaxine hydrochloride was made by dissolving 10mg in 100ml ethanol. It is estimated that the concentration of prepared stock 1 solution was 100μg/ml. The First stock solution was diluted further with ethanol to get a concentration of 10 μg/mL. The solution was scanned between 400 and 200 nm using ethanol as blank by Double Beam Spectrophotometer¹¹.

Linearity curve of Venlafaxine Hcl:

According to A. Jawed et al 2015, Preparation of dilution of 5-30μg/ml, the absorbance of made dilutions were measured at λmax 225.40nm. Then, the linearity curve was plotted by taking concentration on the x-axis and absorbance on y-axis (in Tab no.3 and fig.3).

Sample preparation of Venlafaxine Hcl:

100mg of venlafaxine was weighed accurately and transferred into a 100ml standard volumetric flask. The contents were dissolved in ethanol. This solution was filtered through a (0.45microns) membrane filter. 1 ml of the filtrate was diluted with ethanol to get a concentration of 10µg/ml¹².

Validation of Spectrophotometric method:

1. Accuracy:

Accuracy can be defined as closeness of the test results obtained by the method to the true value. To study the accuracy, 100mg of Venlafaxine was taken, and the powder was used to carry out the analysis. Accuracy studies were conducted by addition of diluted drug solution (10, 15, 20µg/ml) to the sample solution at minimum 3 different concentration levels¹³ and results were presented in Table: 4.

2. Precision:

Depending on the level of agreement among the test results, the precision of an analytical method can be determined by multi-sample collection of homogenous samples¹⁴. As a coefficient of variation (CV), it indicates the results of random error.

2.1 Precision between days and within days:

An individual's precision within a day and between days varies and was shown in Table: 5. Intra-day precision was determined by analysing Venlafaxine for three times in the same day at 225nm. Inter-day precision was determined by analysing the drug daily once for three days at 225nm.

3. Linearity:

It was demonstrated that the method is linear at concentrations of 5 to 25µg/ml. Each aliquot consists of five, ten, fifteen, twenty, and twenty-five µg/ml are prepared from standard solution; Figure: 2, illustrates the calibration curve.

4. Ruggedness:

The different sample solutions were prepared and analyzed with alterations in the analytical situations like different analysts and laboratory conditions are mentioned in Table: 6.

5. Robustness:

The solutions were first prepared and then analysed with changeset in the analytical conditions of different wavelengths are mentioned in Table: 7

RESULTS AND DISCUSSION:

UV Spectroscopy:

Figure 2: λmax of venlafaxine Hcl

Preparation of Calibration curve of Venlafaxine Hcl:

The absorbance for various concentrations measured at 225.4nm are as follows:

Table No: 3. Calibration curve for venlafaxine Hcl

S. No.	Concentration (µg/ml)	Absorbance
1.	5	0.084
2.	10	0.169
3.	15	0.245
4.	20	0.341
5.	25	0.403
6.	30	0.504

Figure 3: At 225.4 nm, the linearity curve for venlafaxine Hcl is measured using UV spectroscopy

Table 4: An analysis of the Regression equation's ideal conditions, optical characteristics, and statistical data

S. No.	Parameters	UV Spectroscopic Method
1.	lmax (nm)	225.4
2.	Beer’s law limits (µg / ml)	5-30
3.	Regression equation (Y*)	Y = 0.0166x+0.0012
4.	Slope (b)	0.0166
5.	Intercept (a)	0.0012
6.	Correlation coefficient (r²)	0.9976
7.	LOD (Limit of Detection) (µg / ml)	0.606
8.	LOQ (Limit of Quantitation) (µg / ml)	1.836

Y= b C + a where C is the concentration of Venlafaxine Hcl (µg / ml) and Y is the absorbance at the respective lmax. **Average of six determinations.

Table 5: Accuracy results for Venlafaxine Hcl at 225.4 nm by UV Spectroscopy

Sample (%)	Initial amount (µg/ml)	Amount added (µg/ml)	*Amount recovered (μg/ml)**	% Recovery ± STDEV*	% RSD
50%	1	10	11.3	101.9± 0.003512	0.501
100%	1	15	15.5	98.6± 0.003512	0.367
150%	1	20	21.4	101.4± 0.001	0.074

**Average of six determinations.

Table No: 6 Precision results of Venlafaxine Hcl at 225.4 nm by Spectroscopy

S. No.	Conc. µg/ml	Intra-day Absorbance	Inter-day Absorbance
1	15	0.922	0.911
2	15	0.912	0.923
3	15	0.971	0.989
4	15	0.888	0.977
5	20	0.998	0.978
6	20	0.979	0.989
7	20	0.999	0.976
8	20	0.988	0.954
	STDEV	0.018176	0.008756
	AVG	0.957	0.962
	%RSD	1.909	0.9233

**Average of six determinations

Table No: 7 Ruggedness Venlafaxine Hcl at 225.4 nm by Spectroscopy

S. No.	Analyst-1		Analyst-2
S. No.	Conc. (μg/ml)	Absorbance	Conc. (μg/ml)	Absorbance
1.	15	0.926	15	0.938
2.	15	0.975	15	0.941
3.	15	0.986	15	0.949
4.	20	0.956	20	0.993
5.	20	0.995	20	0.940
6.	20	0.916	20	0.983
	STDEV	0.005406	STDEV	0.0005709
	AVG	0.959	AVG	0.957
	%RSD	0.5645	%RSD	0.5537

** Average of six determinations.

Table No: 8 Robustness results for Venlafaxine Hcl

S. No.	Condition	Modification	Mean Absorbance ±SD	% RSD (for absorbance)
1.	Wavelength (nm)	223 nm	0.954±0.002656	0.2902
1.	Wavelength (nm)	227nm	0.929±0.002656	0.2276

** Average of six determinations.

Table No: 9 LOD results for Venlafaxine Hcl at 225.4 nm by Spectroscopy

S. No.	Slope	S.D	LOD
1	0.0166	0.018176	0.607

Table No: 10 LOQ results for Venlafaxine Hcl at 225.4 nm by Spectroscopy

S. No.	Slope	S.D	LOQ
1	0.0166	0.018176	1.925

CONCLUSION:

The absorption spectra were recorded in the wavelength region of 200-400 nm in UV method. Drug showed linearity in the different concentration range of 5 - 30 µg / ml in Spectroscopy methods respectively. The spectra are presented as Fig no:2. Beer’s law range was confirmed by the linearity of the calibration curve of Venlafaxine Hcl, which were represented in Fig no: 3.

The optical characteristics such as absorption maxima, Beer’s law limits, Molar absorptivity, Sandell’s sensitivity, slope (b), intercept (C), correlation coefficient (r²) obtained from different concentrations, percent relative standard deviation, LOQ, and LOD values were mentioned in Table no: 4. Based on the results, There is a reasonable degree of precision value in these methods.

The quantitative estimation was carried out on formulation. The quantitative findings underwent statistical analysis to determine standard deviation and standard error values.

The % Relative Standard Deviation values, all below 2, indicate the precision of the methodology and low standard error values indicates the accuracy in the method. The statistical data’s are given in Table no: 5.

Results obtained for the Suggested methods confirm the suitability of these methods for Pure forms. The Accuracy of the methods was confirmed by the recovery studies, and the analytical data are presented in Table no: 5. the % recovery was obtained in between 98.3 - 101.8%.

The Precision by the spectroscopic method was calculated by performing between days and within days precision studies. The values were found to be precise and were presented in Table no: 6.

The results obtained in Ruggedness and Robustness test express the method's precision. The Ruggedness results were shown in Table no: 7 and the Robustness results were shown in Table no: 8 respectively.

ACKNOWLEDGMENTS:

The Mangalayatan University, Aligarh, India supported this work. The authors are thankful to the Agra Public College of Higher Education and Research Centre, Agra for providing the necessary instrumental facilities and chemicals to conduct the research.

REFERENCES:

1. Lavanya K, Sunitha P, Anil Kumar A, Venkata Ramana K. New Simple UV Spectrophotometric Method for determination of venlafaxine hydrochloride in bulk and pharmaceutical dosage forms. International Journal of Pharmaceutical Quality Assurance. 2013; 4(1): 1-3

2. Kumar D, Debata J, Yalamanchili P, et al. Method Development and estimation of venlafaxine hydrochloride in bulk and pharmaceutical dosage forms using UV-VIS Spectrophotometer. International Journal Drug Development and Research. 2013; 5(4): 133-139.

3. Katakam P, Reddy MB, Hwisa NT, Assaleh FH, Dey B, Murthy SV, Chandu BR, Adiki SK. Formulation and evaluation of sustained release venlafaxine tablets using hydrophilic-hydrophobic polymer combinations by melt granulation. J. Sci. Innov. Res. 2014; 3: 49-59.

4. ICH, Q2A Text on validation of analytical procedures, international conference on harmonization.1994.

5. Q2B: Text On; Validation of Analytical Procedures. In International Conference on Harmonization. Federal Register, 1997; 62(96): 27463- 27467

6. Aulton, M.E. Pharmaceutics: The Science of Dosage Form Design. Churchill Livingstone: Edinburgh. 2005; 133.

7. British Pharmacopoeia commission, British pharmacopoeia, Renouf publishing company Limited, 2013.

8. European Pharmacopoeia Vol. II, 6th Ed., (2008) p. 3184

9. Saad MA, El-Sahar AE, Sayed RH, Elbaz EM, Helmy HS, Senousy MA. Venlafaxine mitigates depressive-like behavior in ovariectomized rats by activating the EPO/EPOR/JAK2 signaling pathway and increasing the serum estradiol level. Neurotherapeutics. 2019; Apr 1; 16(2): 404-15. https://doi.org/10.1007/s13311-018-00680-6.

10. D. Singh, A. Saadabadi, Venlafaxine, statpearls, publishing Treasure Island (FL) 2022.

11. Bansode Ashwini S. Analytical Method Development and Estimation of Venlafaxine Hydrochloride in Bulk and Pharmaceutical Dosage Form by UV-Visible Spectrophotometer.2019; 6(10): 131-138.

12. A. Jawed, J. Prajapati, M. Mujahid, and G. O. Elhassan. Development and validation of derivative spectrophotometric method for simultaneous estimation of lornoxicam and eperisone in their synthetic mixture. As. J. Res. Chem. 2015; 8(7): 465-470.

13. Rajashri R. Kulkarni, Dipti G. Phadtare, Ravindra B. Saudagar. UV Spectrophotometric Method Development and Validation of Fluticasone Propionate. Asian J. Res. Pharm. Sci. 2016; 6(2): 135-138. http://doi: 10.5958/2231-5659.2016.00019.9

14. Ladmeera, Hasumati Raj, Vineet Jain. Development and Validation of Analytical Method for Bromhexine Hydrochloride, Chlorpheniramine Maleate and Guaifenesin by Simultaneous Equation Spectroscopic Method. Asian J. Res. Pharm. Sci. 5(2): 2015; 76-82. http://doi: 10.5958/2231-5659.2015.00013.2.

Received on 07.06.2024 Revised on 11.10.2024

Accepted on 04.12.2024 Published on 12.06.2025

Available online from June 14, 2025

Research J. Pharmacy and Technology. 2025;18(6):2533-2536.

DOI: 10.52711/0974-360X.2025.00362

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Creative Commons License.