Comparative Quality Assessment of Branded and Generic Metformin Prolonged-Release Tablets and Glimepiride Tablets using Assay, In-vitro Dissolution Testing and Statistical Approaches (Model-Dependent and Model-Independent Approaches)

 

Deepak Mandal^1,2, Manisha Trivedi², Meenakshi Dahiya², Robin Kumar², Dharam Pal Pathak¹, Nupur Tomar², Rajan Choudhary²

^1,2Quality Assurance, Deepak Mandal, Delhi Pharmaceutical Science and Research University, New Delhi, India.

²Reference Standard Division, Dr. Manisha Trivedi, Indian Pharmacopoeia Commission, Ghaziabad, India.

²Quality Assurance Head, Dr. Meenakshi Dahiya, Indian Pharmacopoeia Commission, Ghaziabad, India.

²Reference Standard Division, Dr. Robin Kumar, Indian Pharmacopoeia Commission, Ghaziabad, India.

¹Pharmaceutical Chemistry, Dr. Dharam pal Pathak, Delhi Pharmaceutical Science and Research University, New Delhi, India.

²Reference Standard Division, Dr. Nupur Tomar, Indian Pharmacopoeia Commission, Ghaziabad, India.

²Reference Standard Division, Mr. Rajan Choudhary, Indian Pharmacopoeia Commission, Ghaziabad, India.

 

ABSTRACT:

Background: This study explores the pharmacological features of metformin hydrochloride and glimepiride, two widely recommended medicines for controlling type 2 diabetes mellitus. Objective: The primary objectives were to assess the dissolving profiles, confirm the uniformity of the active pharmaceutical components, and evaluate conformity to pharmacopoeial standards in branded and generic formulations. Methods: We employed UV spectroscopy and high-performance liquid chromatography (HPLC) to conduct extensive evaluations. The absorption profile of UV spectroscopy revealed the measurement of the concentration of the medication in different formulations. HPLC had provided precise separation and quantitation and proved the purity and concentration of various samples. The dissolving studies were performed to detect the differences in the release of branded and generic preparations. Univariate ANOVA, and t-tests were applied to determine consistency and reproducibility of data through statistical analysis. The use of Graphical representation and interpretation, non mathematical models (f1, f2, and the Rescigno ratio), mathematical models (zero order, first order, Higuchi, Pappas, Sahlin, Hixson-Crowell, Baker-Lader, Kos Meyer-Pappas) used to describe the dissolution profiles. Results: The dissolution studies showed there were major variations between the brand and generic formulations concerning the rate of release which could affect the bioavailability and efficacy of a drug. Consistency and trustworthiness were supported with the help of statistical study. In conclusion, our results emphasize the high importance of standard analytical measures in the process of ensuring drug quality and drug efficacy. The given work contributes insightful experience to the pharmaceutical analysis of the anti-diabetic medications, which benefit establishing the reliable formulations of generics and highlighting the importance of quality control in the pharmaceutical industry.

 

 

1. INTRODUCTION: 

The assurance of the efficacy and safety of pharmaceuticals is essential in the sphere of pharmaceutical sciences¹. The given research takes a new step to inquire into the quality of metformin prolonged-release formulations and their generic substitutes through extended assay and in-vitro dissolution testing.² In the study, the researchers explain the importance of such tests as essential quality control methods that are used to ensure that both branded and generic copies of drugs have high pharmaceutical standards.^3,4 Diabetes mellitus (DM) is a prolonged condition of high sugar blood levels, which requires effective pharmaceutical remedies to control.⁵ Glimepiride and metformin hydrochloride are two of the key medicines used in treating type two diabetic mellitus (T2DM).⁶ Metformin is a biguanide that enhances insulin sensitivity and reduces glucose production in the liver, glimepiride, a member of a sulfonylurea, increases insulin secretion by the pancreatic beta cells.⁷ Since these pharmaceuticals are used widely, it is crucial to ensure that their extent of performance in branded and generic form is assured in terms of quality, efficacy and safety.^8,9 This work utilises high performance liquid chromatography (HPLC) and ultraviolet-visible (UV-Vis) spectroscopy to analyse the assay of metformin and glimepiride formulations.^10,11,12 This HPLC is a strong analysis tool that allows an accurate quantification of a product and also guarantees the detection of contaminants that may be present in the given product.^13,14,15,16 This makes this technique more valid assessing the purity and the potency in the given drug.^17,18 The overall research utilizes current spectroscopic tools like the in the analytical process that was used here is quite proficient as it not only strengthens this study in terms of its findings due to its reliability but also marks the beginning of future computations involving quality assurance of drugs.¹⁹ Through the advanced form of statistical testing, such as the use of univariate ANOVA and the t-tests, the study confirms the reliability and recyclability of its conclusions, which ensures that the findings are scientifically sound and clinically applicable.^20,21,22

 

1.1. Graphical Representation Of Dissolution Profile Data:  Metformin Samples:

 

Fig. 1. % Release vs. Time

Initial time point (0.25hours):

Ref.1 and Ref.2 showed close values (17.78, 18.98). Test samples varied, highest in Test.1 (21.51) and lowest in Test.6 (15.17).

 

Early time point (1hour):

Ref.1 and Ref.2 remained similar (36.13, 35.67). Test.2 and Test.3 were close to reference (36.51, 36.45), while Test.5 and Test.6 showed lower values (31.07, 32.75).

 

Mid time point (3 hours):

Ref.1 and Ref.2 were similar (48.32, 47.81). Test.1 matched Ref.1 (48.22), while Test.2 - 5 showed higher values (59.79 - 58.89). Test.6 was slightly lower (55.15)

 

Later time point (5 hours):

Ref.1 and Ref.2 were close (66.63, 69.19). All tests showed higher values, with Test.4 highest (73.67) and others slightly above references (68.64 -72.95).

 

Final time point (8 hours):

Ref.1 and Ref.2 were similar (93.52, 92.96). Test samples aligned closely, except T3 (88.63). Reference profiles were uniform; tests varied at 3 h but matched by 8 h.

 

1.2. Symbols:

Symbols:

1.     K0, K1, KH, KKP, KHC, KBL, K1, K2 - Rate constants for various drug release models (Zero-order, First-order, Higuchi, Korsmeyer-Peppas, Hixson-Crowell, Baker-Lonsdale, Peppas-Sahlin).

2.     RSQR_ADJ - Adjusted R-square, MSE_ROOT - Root Mean Square Error

3.     AIC - Akaike Information Criterion, MSC - Model Selection Criterion.

4.     n - Exponent, f1 - Difference factor ,f2 - Similarity factor

5.     ζ1, ζ2 - Rescigno indices

 

Table1. List of instruments

Instrument	Brand/Model	Manufacturer
HPLC System	Agilent 1200	Agilent Technologies
Uv-Visible Spectrophotometer	Lambda 35	Perkin Elmer
Dissolution Apparatus	Ds 8000	Lab India
Sonicator	Branson Sonicator	Mettler Toledo
Water Purification System	Integral 3 Q-Pod	Millipore Co. Bedford USA
Ph Meter	Seven Compact Ph/Ion S220	Mettler Toledo
Syringe Filter	RanDisk	Rankem
Digital Weighing Balance	-	Mettler Toledo
Analytical Column	Inertsil (C18 150*4.6mm 5µm)	-
Membrane Filters	Millipore	Axiva
Hot Air Oven	-	-
Glassware	-	Borosil

 

Table2. List of the Chemicals and Reagents

 

Table 3. Metformin Hydrochloride Prolonged-Release 500 mg Tablets

Sample Type	Sample	Assay Results (%)	Time (Hr.)	Dissolution Profile (%)
Branded	R1 (EXERMET 500 SR)	100.25	0.25	17.78
			1	35.49
			3	48.32
			5	66.63
			8	93.52
Branded	R2 (GLUCOFORMIN XL 500)	99.85	0.25	18.98
			1	35.67
			3	47.81
			5	69.19
			8	92.96
Generic	T1 (METFORNIL SR 500)	100.27	0.25	21.50
			1	34.60
			3	48.22
			5	68.64
			8	94.55
Generic	T2 (METFORM SR 500)	101.36	0.25	15.17
			1	32.75
			3	55.15
			5	72.18
			8	93.15
Generic	T3 (DAILYGLIM 500 SR)	101.08	0.25	15.39
			1	31.07
			3	58.89
			5	72.95
			8	90.75
Generic	T4 (METROSE 500 SR)	99.88	0.25	15.49
			1	36.51
			3	59.79
			5	69.81
			8	90.15
Generic	T5 (ELCEPHASE 500 SR)	101.48	0.25	16.61
			1	36.14
			3	58.66
			5	73.67
			8	92.29
Generic	T6 (METFORMIN HCL (J.A))	100.92	0.25	18.38
			1	36.45
			3	60.90
			5	69.94
			8	88.63

All samples met pharmacopoeial standards (API 90 -110%). Both branded and generic forms released >85% within 8 hours, confirming consistent efficacy.

 

Table 4. Glimepiride 1 mg Tablets

Sample Type	Samples	Assay (%)	Dissolution Profile at 30 mins (%)
Branded	R3 (Glimda-1)	92.79	96
	R4 (Glimestar-1)	102.67	99
Generic	T7 Glimepiride HCl (Jan Aushadhi)	99.38	91
	T8 (Glidum-1)	96.29	89
	T9 (Glyzee-1)	101.08	94
	T10 (Glyfic-1)	99.88	83

 

All samples met IP 2022 standards (API 90 -110%). Both branded and generic forms released >75% in 30 minutes, confirming consistent efficacy.

 

Non-Mathematical Models (Model-Independent Approach):

 

Table 5. f1, f2, and Rescigno Index (ζ1, ζ2) for Test Products

Test Product	f1 (Ref.1)	f1 (Ref.2)	f2 (Ref.1)	f2 (Ref.2)	ζ1 (Ref.1)	ζ1 (Ref.2)	ζ2 (Ref.1)	ζ2 (Ref.2)
Test.1	3.20	2.32	81.98	87.72	0.0115	0.0078	0.0132	0.0087
Test.2	7.89	7.46	62.14	61.73	0.0396	0.0342	0.0490	0.0487
Test.3	8.00	7.12	61.02	61.18	0.0422	0.0362	0.0520	0.0511
Test.4	7.54	7.12	62.08	63.14	0.0424	0.0371	0.0509	0.0467
Test.5	10.33	9.54	60.19	61.04	0.0519	0.0451	0.0537	0.0498
Test.6	7.14	6.52	67.39	68.51	0.0360	0.0299	0.0384	0.0339
Overall Statistics	Mean	SE	Mean	SE	Mean	SE	Mean	SE
Mean_R Vs Individual	6.92	0.99	66.78	3.94	0.0341	0.0056	0.0408	0.0067
Mean_R Vs Mean_T	6.18		67.64		0.0323		0.0381

 

The mean f1 (6.18) and f2 (67.64) values fall within acceptable limits, confirming similarity between test and reference profiles. Low Rescigno Index (ζ₁) and minimal errors further support their close equivalence in dissolution behaviour.

 

 

UNIVARIATE ANOVA OUTPUT

Table 6. Anova Results

Source of Variation	Sum of Squares (SS)	Degrees of Freedom (DF)	Mean Square (MS)	F-Value	p-Value	F Critical (F Crit)
Between Groups	50,836.47	1	50,836.47	141.68	3.23E-19	3.96
Within Groups	27,987.87	78	358.82
Total	78,824.33	79

The F-value (141.68 > 3.96) and low P-value (<0.05) indicate significant differences in release over time, confirming a sustained-release profile.

 

T-Test Results

Table 7. p-Values for Pair-wise Comparisons

All p-values >0.05, indicating no significant difference and confirming similarity between test and reference dissolution profiles.

 

MATHEMATICAL MODELS:

(Model-dependent Approach):Table 8. Interpretation Of Data for Different Models

Time (hour)	Ref.1	Ref.2	Test.1	Test.2	Test.3	Test.4	Test.5	Test.6
0.25	17.78	18.98	21.51	15.49	18.38	16.61	15.39	15.17
1	36.13	35.67	34.6	36.51	36.45	36.14	31.07	32.75
3	48.32	47.81	48.22	59.79	60.19	58.66	58.89	55.15
5	66.63	69.19	68.64	69.81	69.94	73.67	72.95	72.18
8	93.52	92.96	94.55	90.15	88.63	92.29	90.75	93.15

 

Table 9. Parameters of the mathematical models and descriptive statistics for the dissolution data

Model	Metric	NO.1	NO.2	NO.3	NO.4	NO.5	NO.6	NO.7	NO.8
Zero Order	K0	10.203	10.112	9.795	10.150	10.039	10.188	10.198	10.177
	RSQR_ADJ	0.5563	0.4377	0.2569	0.3848	0.4717	0.5418	0.6133	0.5808
	MSE_ROOT	21.2688	23.5171	25.0017	24.5673	23.3288	22.2707	20.3130	20.861
	AIC	48.3435	49.5494	50.2840	50.0736	49.4529	48.8959	47.7918	48.1113
	MSC	0.4792	0.2424	-0.0364	0.1525	0.3047	0.4472	0.6167	0.5362
First Order	K1	0.275	0.303	0.298	0.314	0.297	0.293	0.270	0.273
	RSQR_ADJ	0.9068	0.9506	0.9210	0.9575	0.9764	0.9703	0.9177	0.9195
	MSE_ROOT	9.7483	6.9724	8.1497	6.4551	4.9317	5.6693	9.3688	9.1398
	AIC	38.9818	34.9602	36.8325	34.0350	30.8047	32.4775	38.5052	38.2083
	MSC	2.0395	2.6740	2.2056	2.8256	3.4128	3.1836	2.1644	2.1867
Higuchi	KH	30.596	30.634	29.903	30.840	30.393	30.699	30.498	30.498
	RSQR_ADJ	0.9643	0.9652	0.9306	0.9517	0.9617	0.9739	0.9746	0.9724
	MSE_ROOT	6.0301	5.8498	7.6427	6.8831	6.2776	5.3196	5.2010	5.3565
	AIC	33.2179	32.8535	36.0616	34.8055	33.7004	31.7134	31.4427	31.7964
	MSC	3.0002	3.0251	2.3340	2.6972	2.9302	3.3109	3.3415	3.2553
Korsmeyer-Peppas	KKP	33.780	36.080	37.661	36.985	34.929	34.091	32.578	33.250
	n	0.449	0.416	0.381	0.407	0.429	0.446	0.466	0.456
	RSQR_ADJ	0.9633	0.9827	0.9752	0.9734	0.9700	0.9767	0.9716	0.9714
	MSE_ROOT	6.1142	4.1253	4.5684	5.1039	5.5567	5.0270	5.5042	5.4524
	AIC	34.0452	29.3234	30.5477	31.8777	32.8978	31.6957	32.7838	32.6704
	MSC	2.8623	3.6134	3.2530	3.1851	3.0639	3.3139	3.1180	3.1097
Hixson-Crowell	KHC	0.073	0.080	0.080	0.084	0.080	0.078	0.071	0.072
	RSQR_ADJ	0.8986	0.9145	0.8661	0.9258	0.9504	0.9541	0.9102	0.9099
	MSE_ROOT	10.1652	9.1700	10.6123	8.5300	7.1510	7.0465	9.7867	9.6695
	AIC	39.4843	38.2479	40.0008	37.3797	35.2637	35.0869	39.0289	38.8844
	MSC	1.9558	2.1260	1.6775	2.2681	2.6696	2.7487	2.0771	2.0740
Baker-Lonsdale	KBL	0.028	0.029	0.028	0.030	0.028	0.029	0.027	0.027
	RSQR_ADJ	0.9457	0.9880	0.9927	0.9881	0.9821	0.9746	0.9472	0.9521
	MSE_ROOT	7.4384	3.4360	2.4705	3.4227	4.2948	5.2413	7.5070	7.0511
	AIC	35.7365	26.4682	22.5097	26.4219	29.1455	31.5354	35.8466	35.0949
	MSC	2.5804	4.0893	4.5927	4.0944	3.6893	3.3406	2.6075	2.7056
Peppas-Sahlin	K1	19.688	38.230	40.504	38.607	35.138	34.434	16.099	13.475
	K2	14.281	-3.458	-4.302	-3.800	-3.219	-2.920	16.660	19.899
	M	0.297	0.562	0.553	0.603	0.660	0.644	0.292	0.273
	RSQR_ADJ	0.9532	0.9908	0.9901	0.9918	0.9959	0.9893	0.9631	0.9625
	MSE_ROOT	6.9102	3.0013	2.8887	2.8354	2.0623	3.4060	6.2773	6.2390
	AIC	35.7876	25.7803	25.3213	25.0979	21.2777	27.2981	34.6349	34.5615
	MSC	2.5719	4.2039	4.1241	4.3151	5.0006	4.0468	2.8095	2.7945

K0: Zero-order rate constant; K1: First-order rate constant; KH: Higuchi constant; KKP: Korsmeyer-Peppas constant;

n: Release exponent; KHC: Hixson-Crowell constant; KBL: Baker-Lonsdale constant; K1 and K2: Release exponents;

RSQR_ADJ: Adjusted R²; MSE_ROOT: Root mean square error; AIC: Akaike Information Criterion; MSC: Model selection criterion.

 

2. MATERIALS AND METHOD:

2.1. Materials:

Metformin Hydrochloride Prolonged-Release 500 mg Tablets:

 

Reference (Branded):

Metformin Hydrochloride Prolonged-Release 500 mg Tablets (Reference No. R1, R2)

 

Test (Generic):

Metformin Hydrochloride Prolonged-Release 500 mg Tablets (Test No. T1, T2, T3, T4, T5, T6)

 

Glimepiride 1 mg Tablets:

Reference (Branded):

Glimepiride 1 mg Tablets (Reference No. R3, R4)

 

Test (Generic):

Glimepiride 1 mg Tablets (Test No. T7, T8, T9, T10)

 

2.2. Methods:

Metformin Hydrochloride (UV Spectrophotometry)

Diluent: Water

 

The assay of Metformin Hydrochloride, A 20 mg working standard was dissolved in water, diluted, and filtered (0.45 µm PVDF). For the sample, 20 tablets were powdered, and an equivalent of 100 mg was dissolved, diluted, and filtered. Absorbance was measured at 232 nm with water as blank.

 

For dissolution testing, Conducted in 1000 mL phosphate buffer (pH 6.8) at 37 ± 0.5 °C, 100 rpm (paddle). Samples were collected at 15 min, 1 h, 3 h, 5 h, and 8 h, diluted, filtered, and analyzed at 232 nm. The standard solution was prepared as per assay.

 

Glimepiride (HPLC):

Chromatographic Conditions:

·       Column: Inertsil ODS, 150 x 4.6 mm, 5 µm

·       Wavelength: 228 nm

·       Injection Volume: 10 µl

·       Flow Rate: 1.0 ml/min

·       Mobile Phase: 50:50 buffer: acetonitrile

·       Diluent: 90:10 acetonitrile: water

 

The assay for Glimepiride - A 10 mg IPRS standard was dissolved in 70 mL diluent, sonicated, diluted to 100 mL, and filtered (0.45 µm PVDF). For the sample, 20 tablets were powdered, and an amount equivalent to 10 mg was dispersed in solvent to prepare a 0.01% w/v solution, then filtered. Injections were run in the sequence: blank → standard → sample → bracketing standard. System suitability criteria: theoretical plates ≥2000, tailing factor ≤2.0, RSD ≤2.0%.

 

For dissolution testing, conducted in 900 mL phosphate buffer (pH 7.8) using a paddle at 75 rpm, 37 ± 0.5 °C. A 125 mg IPRS standard was prepared in solvent mixture (90:10 acetonitrile: water), diluted, and filtered. Samples were taken at 30 min, diluted, filtered, and analyzed, with blank, standard, and sample injections used to quantify dissolved drug.

 

Applied methods to compare dissolution profiles:

Statistical Analysis (ANOVA and t-tests)

 

Analysis of Variance (ANOVA):

·       ANOVA was used to test whether mean differences among groups were statistically significant.

 

t-tests:

·       These were utilised to compare the means between two groups. Both ANOVA and t-tests were done using [MS Excel 2019], with significance levels set at p < 0.05.

 

Model Independent Methods (Non-Mathematical Models: f1, f2, Rescigno ratio).

 

f1 (Difference Factor):

f2 (Similarity Factor):

f2=50×log {[1+  (R_t−T_t)²] ^−0.5×100}

Rescigno Ratio ζ1

 

Rescigno Ratio ζ2

 

where:

·       D_i,T, and D_i,R are the Dissolution values at time i for test and reference products.

·       dD_i,T/dt  and dD_i,R/dt are the Dissolution values at time i for test and reference products.

·       A ratio close to 1 indicates that the test and reference products have similar release profiles.

 

EXPERIMENTAL:

Metformin hydrochloride and glimepiride tablets were analyzed using UV spectroscopy and HPLC to compare branded and generic formulations.

·       Metformin: Assayed at 232 nm by UV; dissolution tested in 1000 mL phosphate buffer (pH 6.8) at 37 °C, 100 rpm, with samples taken up to 8 h.

·       Glimepiride: Quantified by HPLC (Inertsil ODS column, 50:50 buffer–acetonitrile); dissolution in 900 mL phosphate buffer (pH 7.8) at 37 °C, 75 rpm, sampled at 30 min.

 

3. RESULTS and DISCUSSION:

The study compared branded and generic Metformin HCl prolonged-release and Glimepiride tablets using UV spectroscopy, HPLC, and in-vitro dissolution tests, providing insights into quality, dissolution, and bioequivalence across formulations

 

3.1. Metformin Hydrochloride Prolonged Release 500 mg:

At 0.25 h, references were similar (R1: 17.78%, R2: 18.98), while generics varied (T1 highest 21.51%, T6 lowest 15.17%).

 

Early time point (1 hour): The dissolution values for R1 and R2 remained close (36.13% and 35.67%, respectively), with T2 and T3 nearly matching the reference profiles, whereas T5 and T6 showed lower dissolution values.

·       Mid time point (3 hours): At this point, branded samples were similar (R1: 48.32%, R2: 47.81), while generics, especially T2 (59.79%) and T3 (60.19%), showed higher dissolution, indicating faster release.

·       Later time point (5 hours): Branded samples remained consistent, while generics showed higher solubility, with T4 highest (73.67%).

·       Final time point (8 hours): Dissolution of branded and generics converged, with all nearing reference levels except T3, which stayed slightly lower.

All samples met pharmacopoeial standards (API 90 -110%). Both branded and generic forms released >85% within 8 h, confirming consistent efficacy.

 

3.2. Glimepiride 1 mg:

Statistical Analysis:

·       Model-independent techniques: f1 and f2 confirmed similarity between generic and branded profiles, while Rescigno ratios supported the closeness of their release characteristics.

·       Model-based approaches: Dissolution data were fitted to various models; First Order, Higuchi, and Korsmeyer-Peppas gave the best fit, indicating a complex release mechanism involving diffusion and polymer relaxation.

 

ANOVA and t Tests:

ANOVA showed significant changes in release over time, confirming sustained release. Pairwise t-tests found no significant differences between test and reference profiles, supporting therapeutic similarity.

 

4. CONCLUSION:

This study highlights the importance of rigorous analysis to ensure the quality and efficacy of anti-diabetic drugs, focusing on metformin prolonged-release and glimepiride. Branded and generic formulations were compared using UV spectroscopy, HPLC, and in-vitro dissolution testing. Drug release kinetics were evaluated with model-dependent (Zero Order, First Order, Higuchi, Korsmeyer-Peppas, Hixson-Crowell, Baker-Lonsdale) and model-independent (f₁, f₂, Rescigno ratio) approaches. Results showed time-dependent differences in dissolution affecting bioavailability, validated through ANOVA and t-tests. The findings support the reliability of generic formulations and underline the need for thorough evaluation to strengthen diabetes management.

 

5. LIST OF ABBREVIATIONS:

1.     T2DM - Type 2 Diabetes Mellitus

2.     HPLC - High-Performance Liquid Chromatography

3.     API - Active Pharmaceutical Ingredient

4.     SR - Sustained Release

5.     XR - Extended Release

6.     USP - United States Pharmacopeia

7.     IPRS - Indian Pharmacopoeia Reference Standard

8.     PVDF - Polyvinylidene Fluoride

9.     NMR - Nuclear Magnetic Resonance

 

 

6. CONFLICT OF INTEREST:

The authors declare no financial or personal conflicts of interest. The study was conducted without external funding, and the authors take full responsibility for the results.

 

7. ACKNOWLEDGEMENTS:

My special thanks to the Indian Pharmacopoeia Commission, which has generously assisted me both with resources and moral support, thus performing a great role in the successful completion of this work.

 

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Received on 03.08.2025      Revised on 05.12.2025 Accepted on 02.03.2026      Published on 01.07.2026 Available online from July 04, 2026 Research J. Pharmacy and Technology. 2026;19(7):2926-2932. DOI: 10.52711/0974-360X.2026.00417 © RJPT All right reserved
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