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INTRODUCTION
Pantoprazole sodium is a benzimidazole derivative and a Potent Proton-Pump Inhibitor (PPI) used to treat Gastroesophageal Reflux Disease (GERD), peptic ulcers, and Zollinger-Ellison syndrome (Gang et al., 2004). By irreversibly inhibiting the H+ / K+ -ATPase enzyme activity in gastric parietal cells, the drug shows its therapeutic action, thereby reducing gastric acid secretion (Mei-Juan et al., 2005). Despite its high therapeutic efficacy, Pantoprazole sodium is highly unstable in acidic conditions and undergoes rapid degradation in the stomach, which can significantly reduce its bioavailability.
To overcome this limitation to protect the drug from the acidic gastric environment, enteric coating is employed to ensure its release in the alkaline pH of the intestine, where absorption occurs. Enteric polymers are designed to remain intact at low pH but dissolve at higher intestinal pH levels, thereby enhancing drug stability and therapeutic effectiveness. Among the commonly used enteric polymers, Eudragit is used in the duodenum (pH>5.5), preventing drug hydrolysis by acid and delivering the drug to the main site of absorption in the small intestine (Naikwade et al., 2008). Recent technologies in enteric coating have focused on pH-sensitive methacrylic acid copolymers like Eudragit L100 and RS100, which provide much finer trigger-release profiles and mechanical stability than traditional phthalate-based polymers (Neha et al., 2021; Arun et al., 2009; Nitesh et al., 2009).
In addition to enteric protection, fast offset of action is a very important quality attribute of PPIs. This has been done by attaching super disintegrants to the core of the pills. Kollidon ® AP (Crospovidone) and sodium starch glycolate (Explotab) are substances that speed up the breakup process of pills through swelling, wicking, and structural deformation mechanisms (Salunkhe et al., 2009). Where Sulphur-coated systems are employed, the super disintegrant has to cause immediate disintegration when the enteric shell is dissolved in the intestinal fluid, thus ensuring the timely dissolution and absorption (Mohamed et al., 2009). However, even with an extensive application of PPIs, there is still an obvious increase in disparities between the dissemination of super disintegration classes in the framework of enteric-coated core maximization. A high number of formulations are unsuitable due to a lack of acid resistance or slow release in the intestine, which affects bioavailability. In modern literature, it is emphasized that there is a need to achieve an optimal polymer 9 disintegrant ratio, which contributes to gastric stability and rapid intestinal intake (Aswar et al., 2009; Vikas, 2010).
The main purpose of the research is to develop and test Pantoprazole sodium enteric- coated tablets by maximizing the core using different super disintegrants and using the best enteric polymer system. This research aimed to reach a solid formulation (EC-PF8) with an Eudragit RS100 analyzed acid resistance and a rapid, complete release of the drug into the intestinal space to promote the overall stability and treatment of the drug.
MATERIALS AND METHODS
Pantoprazole sodium was obtained as a gift sample from Dhamtec Pharm, Mumbai. The super disintegrants used were Kollidone-CL (crospovidone), Explotab (sodium starch glycolate), and HPMC (Hydroxypropyl Methylcellulose). The enteric coating polymers that were used were Eudragit 100 (methacrylic copolymer type A), Eudragit 100(B), ammonia methacrylate, and Polyvinyl Acetate Phthalate (PVAP). Other analytical-grade excipients included mannitol (diluent), PVP K30 (binder), Aerosil (glidant), and magnesium stearate (lubricant) as shown in Table 1. The objective of using Eudragit RS 100 in these formulations to modulate drug release kinetics which enhance residence time and increase therapeutic performance simultaneously.
| Formulation | PF1 | PF2 | PF3 | PF4 | PF5 | PF6 | PF7 | PF8 | PF9 |
|---|---|---|---|---|---|---|---|---|---|
| Pantoprazole | 40 (mg) | ||||||||
| Explotab (mg/1 g) | 5 | 7.5 | 10 | ||||||
| Kollidone (mg/1 g) | 5 | 7.5 | 10 | ||||||
| HPMC (mg/1 g) | 5 | 7.5 | 10 | ||||||
| PVPK 30 | 4 (mg/1 g) | ||||||||
| Mannitol | Sufficient Quantity | ||||||||
| Aerosil | 2.5 (mg/1 g) | ||||||||
| Magnesium stearate | 2 (mg/1 g) | ||||||||
| Total weight | 200 (in mg) |
Pre-Formulation Studies
API Characterization for Pantoprazole Sodium was performed.
Spectrophotometric Method
An analytical method for Pantoprazole Sodium was developed using UV-visible spectrophotometry. The maximum absorption wavelength (λmax) of the drug was determined by scanning a 10 μg/mL solution in methanol over a wavelength range of 200-400 nm.
Calibration Curve of Pantoprazole 0.1N HCl
In 10 mL volumetric flasks, aliquots of standard stock solution (1000 µg/mL) were diluted with 0.1N HCl to obtain concentrations of 4, 8, 12, 16, and 20 µg/mL. The absorbance of each solution was measured in triplicate at 285 nm using a UV-visible spectrophotometer Table 2, Figures 1 and 2.
| Concentration (w/w) | Absorbance at 285 (nm) |
|---|---|
| 0 | 0 |
| 2 | 0.202 |
| 4 | 0.395 |
| 6 | 0.558 |
| 8 | 0.745 |
| 10 | 0.912 |
Calibration Curve in a Phosphate Buffer of 6.8 pH
In 10 mL volumetric flasks, aliquots of the standard stock solution (1000 µg/mL) were diluted with phosphate buffer (pH 6.8) to obtain concentrations of 4, 8, 12, 16, and 20 µg/mL. Absorbance values were recorded in triplicate for the solutions at 285 nm.
Development of Formulation and its Compatibility Studies
Solubility Analysis
The solubility of the drug in other solvents such as water, ethanol, methanol, chloroform, and acetone was also looked at to determine the hydrophilic-lipophilic balance of the drug and thus offer an insight into which solvent was best to use in coating.
Drug-Excipient Compatibility (FT-IR)
To determine the chemical stability of the formulation, Fourier Transform Infrared spectroscopy was used based on the 2 mg KBr pellet technique. The pure drug and the optimized formulation (EC-PF8) were obtained as spectra in the range of 400-4000 cm-1, which allowed revealing possible interactions between the drug and the polymer.
Cores Zwalla (Wet Granulation) Wet Preparation
Wet granulation was used to manufacture core tablets and guarantee homogeneous distribution of the drug, and increase the flow properties. It was sifted using a 30-mesh screen with 1 Pantoprazole sodium, PVP K30, and the selected super disintegrant, which is Explotab, Kollidone, and HPMC. The solution was mixed with 2M mannitol as a diluent. The resulting mixture was granulated with the help of an appropriate binder solution, dried, and sieved. Aerosil and magnesium stearate were used to lubricate 4 g of granules before compression. The compression was done using a rotary tablet machine using an 8mm round, deep-concave tooling, aiming at a target weight of 200 mg. Wet granulation was considered a better method than direct compression to enhance the compressibility of the mannitol-pantoprazole mixture and maintain the structure of the mixture upon which coating would follow.
Enteric Coating Process
Entry of the core formulation (PF8) into the enteric coating was due to optimized disintegration and dissolution characteristics. The solvent-evaporation method was used with the help of a coating pan. The coating solutions Eudragit L 100, PVAP, and Eudragit 100 RS were dissolved in acetone at 4, 6, and 8 w/w, respectively. For plasticization, PEG 400 (1.5% w/w) was incorporated to enhance the flexibility of films and to reduce cracking. The solution was applied to pre-warmed pills of core at a rate of 3 RMP, until the desired weight increase was achieved as shown in Table 3 (Suresh Kumar et al., 2024; Singh et al., 2025; Song Huang et al., 2026).
| Ingredients | EC-PF1 | EC-PF2 | EC-PF3 | EC-PF4 | EC-PF5 | EC-PF6 | EC-PF7 | EC-PF8 | EC-PF9 |
|---|---|---|---|---|---|---|---|---|---|
| Eudragit L 100 | 40 mg/1 g | 60 mg/1 g | 80 mg/1 g | - | - | - | - | - | - |
| PVAP (%W/W) | - | - | - | 40 mg/1 g | 60 mg/1 g | 80 mg/1 g | - | - | - |
| Eudragit RS100 (%W/W) | - | - | - | - | - | - | 40 mg/1 g | 60 mg/1 g | 80 mg/1 g |
| PEG | 15 mg/g | ||||||||
| Acetone | Sufficient Quantity |
Evaluation tests for Tablets
Pre-compression Parameters
Attributes of a given granule (Angle of Repose, Bulk density, tapped density, Carr index, as well as Hauser’s ratio) were also evaluated to monitor the best flowability and compressibility according to USP standards (Muhamed et al., 2010; Thiruganesh et al., 2010).
Post-compression Parameters
Compressed tablets (core and coated) were subjected to standard quality-control tests. Weight variation was determined by individually weighing 20 tablets to confirm compliance with USP specifications (Chetan et al., 2010; Ghule Prashant et al., 2010). For tablets weighing more than 200 mg, the permitted deviation is within ±7.5%.
Tablet hardness and friability tests were performed to ensure adequate mechanical strength during handling and transportation. Hardness was measured using a Monsanto hardness tester with a target range of 3.5-5.5 kg/cm². Friability testing was conducted using a Roche friabilator, and % age weight loss was maintained below 1%, as per pharmacopeial limits (Rasika et al., 2010; Shibu, 2014).
Disintegration time was evaluated using a USP disintegration apparatus to assess the efficiency of different superdisintegrants incorporated in the formulations. Acid stage testing was also conducted to evaluate tablet behavior under simulated gastric conditions prior to further dissolution assessment (Vivek et al., 2011; Joshikk et al., 2022).
In vitro Dissolution Investigations
To maintain a homogeneous exposure of the enteric film to the dissolution media, dissolution testing was done using USP Apparatus I (basket) at 50 RPM. To determine the acid stage, the resistance of academia was tested after 2 hr of incubation with 0.9 L of 0.1 Normality of Hydrochloric acid (pH 1.2) in the presence of tablets were conducted at 37ºC. The acid stage was followed by the buffer stage, a step during which the phosphate buffer with a pH of 6.8 was added, and 15, 30, 45, 60, and 120-min periods were used to sample. Then the samples were analyzed using UV 285 nm using UV-visible spectroscopy (Sharma et al., 2016).
Stability Studies
Stability studies of the optimized formulation (EC-PF8) were conducted in accordance with ICH guideline Q1A (R2) to evaluate the stability of the tablets under different storage conditions (Abdul Samad et al., 2020; Singh, 2024).
The tablets were packed in suitable containers and stored under the following conditions:
- Long-term storage conditions: 25°C ± 2°C/60% RH ± 5% RH.
- Accelerated storage condition: 40°C +/ -2°C/75% RH +/ -5% RH.
Samples were evaluated at predetermined intervals of 1 and 3 months for 1 and 3 months were studied with physical appearance, drug content (assay), and in vitro dissolution characteristics to assess formulation stability.
RESULTS
Pantoprazole sodium is a white to half-white crystalline powder exhibiting weakly basic characteristics. It is freely soluble in water and ethanol, slightly soluble in an acidic buffer with pH 7.4, and is insoluble in n-hexane. The melting point of pantoprazole sodium ranges between 137.5ºC -145.5ºC. The sample of the drug had the highest wavelength of absorption (λmax), which was 285 nm. The absorption bands correspond to the major functional group shown in Table 4, the pure drug, and the optimized EC-PF8 formulation. The FT-IR spectra of pantoprazole pure drug and enteric coated formulation, EC-PF8 were shown in Figures 3A-3B.
| Sl. No. | Functional group | Observed Range (nm) | Pure drug (nm) | Optimized EC-PF8 (nm) |
|---|---|---|---|---|
| 1 | NH (Secondary amine) | 3420-3632 | 3632.55 | 3632.43 |
| 2 | C=O (Carbonyl group) | 1640-1708 | 1758.77 | 1708.92 |
| 3 | C=N (Imine group) | 1019-1411 | 1271.15 | 1265.67 |
| 4 | C-O (Alcohol group) | 1062-1150 | 1062.95 | 1019.12 |
| 5 | C-F (Fluro group) | 893-1411 | 1150.61 | 1112.86 |
Evaluation of parameters of Pantoprazole Tablets
Tables 5 and 6 show that the angle of repose from batches PF1 to PF9 had an angle of repose within the 25-30 range, which was within acceptable limits of flow behaviour. The formulated blend had a bulk density of between 0.4 and 0.5 g/mL, and a tapped density of between 0.5 and 0.6 g/mL. It was established that the % age compressibility of the batches PF1-PF9 was between 17% and was termed as excellent. Batches PF1 through PF9 exhibited a Hausner ratio of between 1.11 and 1.21; hence, indicating good flow attributes. The hardness of prepared batches PF1-PF9 was held within the range of 3.4 -3.6 kg/cm2. The % age friability of PF1 to PF9 batches was less than 1% w/w. The range of assay values of batches PF1-PF8 was acceptable, ranging between 90 and 110% w/w. Formulation PF8 contained optimal concentration levels of Kollidon and produced desirable flow properties and released 100.1% of the drug in 45 min which was exhibited in Table 7. The normal plot of Pantoprazole showed that it was very linear with an R2 of 0.9988 in 0.1N HCl, which was sufficient to obey the law of Beer-Lambert. The typical plot of Pantoprazole was very satisfactory, and the R2 was 0.9986, which also justifies the Beer-Lambert law.
| Formulations | Angle of repose (θ) | Loose Bulk Density (g/mL) | Tapped Bulk Density (g/mL) | % Compressibility | Hausner’s ratio |
|---|---|---|---|---|---|
| PF1 | 26.54±0.14 | 0.44±0.04 | 0.51 ±0.05 | 11.83±0.04 | 1.01±0.04 |
| PF2 | 27.46±0.11 | 0.44±0.02 | 0.51 ±0.03 | 11.83±0.03 | 1.13±0.05 |
| PF3 | 27.37±0.16 | 0.44±0.02 | 0.53±0.02 | 11.98±0.02 | 1.03±0.05 |
| PF4 | 24.33±0.17 | 0.45±0.01 | 0.53±0.07 | 14.09±0.04 | 1.05±0.04 |
| PF5 | 25.11±0.10 | 0.44±0.04 | 0.52 ±0.06 | 14.34±0.08 | 1.10±0.07 |
| PF6 | 28.67±0.13 | 0.45±0.09 | 0.51 ±0.05 | 14.33±0.05 | 1.10±0.06 |
| PF7 | 27.34±0.12 | 0.51±0.07 | 0.61±0.04 | 15.46±0.04 | 1.10±0.08 |
| PF8 | 24.67±0.15 | 0.58±0.05 | 0.67±0.01 | 18.27±0.02 | 1.19±0.01 |
| PF9 | 27.55±0.11 | 0.50±0.04 | 0.57 ±0.04 | 18.48±0.06 | 1.24±0.02 |
| Formulation | Weight variation | Hardness (kg/m2) | Thickness (mm) | Friability (%) | Disintegration time (in Sec) | Assay% (w/w) |
|---|---|---|---|---|---|---|
| PF1 | 201 | 3.12 | 2.4 | 0.41 | 104 | 99.7 |
| PF2 | 203 | 3.26 | 2.1 | 0.43 | 108 | 99.6 |
| PF3 | 203 | 3.31 | 2.4 | 0.49 | 67 | 100.1 |
| PF4 | 200 | 3.12 | 2 | 0.47 | 65 | 98.7 |
| PF5 | 203 | 3.36 | 2.2 | 0.28 | 64 | 98.6 |
| PF6 | 203 | 3.27 | 2.1 | 0.29 | 60 | 99.1 |
| PF7 | 202 | 3.31 | 2.4 | 0.17 | 48 | 99 |
| PF8 | 200 | 3.49 | 2.1 | 0.17 | 10 | 100.1 |
| PF9 | 203 | 3.49 | 1.9 | 0.25 | 104 | 99.1 |
| Time (in hr) | PF1 | PF2 | PF3 | PF4 | PF5 | PF6 | PF7 | PF8 | PF9 |
|---|---|---|---|---|---|---|---|---|---|
| 6.8 pH Phosphate Buffer | |||||||||
| 0.25 | 21.9 | 37.9 | 14.1 | 32.9 | 57.9 | 49.1 | 32.9 | 53.9 | 51.2 |
| 0.5 | 44.9 | 51.8 | 37.9 | 51.9 | 75.1 | 75.9 | 77.7 | 91.9 | 79.9 |
| 0.75 | 62.4 | 71.9 | 58.7 | 67.9 | 89.9 | 91.8 | 90.9 | 100.1 | 89.9 |
| 1 | 75.1 | 84.9 | 71.1 | 80.1 | 98.1 | 99.8 | 97.9 | 100.7 | 100.1 |
In vitro Drug Release tests
All formulations were dissolved under USP apparatus I, and the dissolution media was 0.1⁻ phosphate buffer of 6.8 -pH with 5.3 hr followed by 2 hr of study. Findings of the in vitro dissolution of formulations EC-PF1-EC-PF9 are provided in Table . The releases of the drugs versus time cumulative % drug release versus time plots, which are represented by Figures 4A-4B, show the comparisons of the % CDR of the formulations EC-PF1 to EC-PF9.
Table 8 shows the evaluated parameters of enteric-coated pantoprazole sodium; the change in the weights across all batches EC-PF1 through EC-PF9 was within the 5-% acceptable difference. In the case of formulated batches EC-PF1 to EC-PF9, the disintegration time ranged between 168 sec and 70 sec with a change in the concentration of the super disintegrant. The formulation EC-PF8 contained optimal concentrations of Kollidon, exhibited desirable flow properties Table 9 and released 100.16% of the drug in 45 min. The formulation EC-PF8, which had the highest drug release, is shown in Table 10 exhibits the absorbance values of enteric-coated pantoprazole sodium.
| Formulations | Weight variation | Hardness (kg/m2) | Thickness (mm) | Friability (%) | Disintegration time (in Sec) | Acid resistance time (in hr) | Assay % (w/w) |
|---|---|---|---|---|---|---|---|
| EC-PF1 | 207 | 3.38 | 2.6 | 0.41 | 164 | 2 | 101.9 |
| EC-PF2 | 210 | 3.54 | 2.3 | 0.4 | 168 | 2 | 101.4 |
| EC-PF3 | 215 | 3.51 | 3.1 | 0.58 | 117 | 2 | 103.1 |
| EC-PF4 | 209 | 3.44 | 2.2 | 0.56 | 85 | 2 | 92.9 |
| EC-PF5 | 211 | 3.4 | 2.4 | 0.41 | 104 | 2 | 98.9 |
| EC-PF6 | 215 | 3.41 | 2.1 | 0.41 | 90 | 2 | 98.4 |
| EC-PF7 | 207 | 3.39 | 2.4 | 0.49 | 70 | 2 | 101.6 |
| EC-PF8 | 214 | 3.51 | 2.5 | 0.47 | 78 | 2 | 101.2 |
| EC-PF9 | 215 | 3.48 | 2.4 | 0.47 | 166 | 2 | 99.3 |
| Time | EC-PF1 | EC-PF2 | EC-PF3 | EC-PF4 | EC-PF5 | EC-PF6 | EC-PF7 | EC-PF8 | EC-PF9 | Aciban |
|---|---|---|---|---|---|---|---|---|---|---|
| 0.1N HCl Acidic Buffer | ||||||||||
| 1 hr | - | - | - | - | - | - | - | - | - | - |
| 2 hr | - | - | - | - | - | - | - | - | - | - |
| 6.8 pH phosphate buffer | ||||||||||
| 15 min | 20.9 | 34.74 | 14.12 | 31.13 | 54.19 | 48.05 | 34.2 | 51.18 | 47.19 | 35.45 |
| 30 min | 40.93 | 49.34 | 37.14 | 47.14 | 71.91 | 71.17 | 73.31 | 84.36 | 75.07 | 55.16 |
| 45 min | 56.51 | 66.34 | 53.17 | 60.96 | 85.47 | 84.46 | 85.72 | 100.16 | 84.6 | 69.84 |
| 60 min | 71.19 | 79.81 | 66.18 | 72.94 | 93.61 | 93.09 | 92.48 | 100.16 | 94.15 | 87.57 |
| 120 min | 100.4 | 98.9 | 99.6 | 99.1 | 99.9 | 99.1 | 97.9 | 100.16 | 99.6 | 98.95 |
| Time | EC-PF1 | EC-PF2 | EC-PF3 | EC-PF4 | EC-PF5 | EC-PF6 | EC-PF7 | EC-PF8 | EC-PF9 | Aciban |
|---|---|---|---|---|---|---|---|---|---|---|
| 0.1N HCl Acidic Buffer | ||||||||||
| 1 hr | - | - | - | - | - | - | - | - | - | - |
| 2 hr | - | - | - | - | - | - | - | - | - | - |
| 6.8 pH phosphate buffer | ||||||||||
| 15 min | 0.676 | 0.143 | 0.474 | 0.986 | 0.18 | 0.198 | 0.998 | 0.179 | 0.157 | 0.124 |
| 30 min | 0.142 | 0.158 | 0.124 | 0.142 | 0.211 | 0.242 | 0.278 | 0.24 | 0.244 | 0.191 |
| 45 min | 0.191 | 0.248 | 0.181 | 0.185 | 0.276 | 0.27 | 0.248 | 0.316 | 0.275 | 0.27 |
| 60 min | 0.191 | 0.254 | 0.219 | 0.271 | 0.282 | 0.272 | 0.279 | 0.316 | 0.274 | 0.283 |
| 120 min | 0.346 | 0.374 | 0.319 | 0.347 | 0.305 | 0.306 | 0.342 | 0.316 | 0.327 | 0.333 |
Among all 9 enteric-coated formulations, Formulation EC-PF8 was selected for stability studies based on release characteristics. The studies were carried out at long-term storage 25°C±2°C/60% RH and accelerated storage conditions at 40°C±2°C/75% RH, which is shown in Table 11.
| Sl. No. | Time points (hr) | Initial (±) | Cumulative % drug release | |||
|---|---|---|---|---|---|---|
| 25°C ± 2°C /60 %RH | 40°C ± 2°C /75% RH | |||||
| 1st month | 3rd month | 1st month | 3rd month | |||
| 1 | 1 hr | 0 | 0 | 0 | 0 | 0 |
| 2 | 2 hr | 0 | 0 | 0 | 0 | 0 |
| 3 | 15 min | 50.18 | 48.9 | 46.9 | 49.5 | 48.2 |
| 4 | 30 min | 84.96 | 84 | 81.3 | 81.6 | 81.3 |
| 5 | 45 min | 100.1 | 97.9 | 95.3 | 95.7 | 93 |
| 6 | 60 min | 100.46 | 97.9 | 95.4 | 98.7 | 98.8 |
| 7 | Assay | 100.1 | 97.8 | 97.9 | 99.6 | 99.9 |
DISCUSSION
The drug exhibits pH-dependent solubility and is unstable under acidic conditions, necessitating enteric coating in oral dosage forms to protect it from gastric degradation. In the present study, Eudragit RS 100 was intentionally selected not as a conventional enteric polymer but as a controlled-permeability coating material to regulate drug diffusion and achieve a sustained-release profile in the gastrointestinal environment. All basic parameters showed no significant changes were observed in physical characteristics and dissolution profiles during the storage period, indicating stability of the optimized formulation. The characteristic peaks with only minor shifts in their positions, shown by the optimized EC-PF8 formulation, indicate the absence of any significant chemical interaction between the drug and excipients. Thus, confirming the compatibility of the drug with the formulation and preservation of its chemical structure.
In the evaluation parameter study on pantoprazole sodium core, the change in the weights across all batches PF1 through PF9 was within the 5-% acceptable difference. In the case of formulated batches PF1-PF9, the disintegration time ranged between 108 sec and 10 sec with a change in the concentration of the super disintegrant. The formulation PF8, which had the highest drug release, had to be used in coating. The faster disintegration observed in PF8 may be attributed to the wicking and deformation mechanisms of Kollidone (crospovidone), which enable rapid water uptake and tablet rupture. In contrast, Explotab predominantly acts through swelling, resulting in comparatively slower disintegration. At different concentrations, three different coating polymers were used. 10 sec disintegration refers to the optimized core tablet (PF8). EC-PF formulations represent enteric-coated tablets that remain intact in acidic media and disintegrate only after the coating dissolves at intestinal pH. The formulation EC-PF8, which had the highest drug release and exhibits the desirable flow properties. The stability study on formulation, EC-PF8 shows that there were no significant changes in their physical appearance. It was observed that the initial drug content of the sample was analyzed after 1 and 3rd month of storage. Hence, it can be concluded that the strength of EC-PF8 with 98.8% release and 99.9% assay after 3 months at 40oC±2°C/75% RH.
Stability studies of the optimized formulation EC-PF8 were conducted under long-term (25°C±2°C/60% RH ± 5% RH) and accelerated conditions (40°C±2°C/75% RH ± 5% RH) for up to 3 months. During this period, the formulation was evaluated for physical appearance, drug content, and in vitro dissolution performance. The results showed no significant changes in assay values or dissolution characteristics, indicating that the enteric coating effectively protected the acid-labile drug from degradation. Within the scope of the present study, no observable evidence of degradation or impurity formation was detected based on the evaluated parameters, suggesting that the optimized enteric coating system maintained the stability of pantoprazole during storage.
CONCLUSION
This research study found a stable, high-quality enteric-coated Pantoprazole tablet that has high acid resistance and fast drug release in intestinal environments. The compatibility of drugs and excipients was verified using FT-IR spectroscopy, and no interactions were observed. Core tablet powder exhibits favourable micromeritic properties as follows: angle of repose <30°C, and the Carr’s index 12-18%. Nine formulations (PF1-PF9) were tested that were prepared by wet granulation, where mannitol was used as a diluent and super disintegrants; PF8 (10% of Kollidone) was optimised due to its outstanding disintegration time (10 sec), friability (0.16 %), and highest release (100.6%) in pH 6.8 phosphate buffer. Enteric-Coated (EC-PF8) cores were then enteric-coated at 4, 6, or 8% levels with Eudragit RS 100, L, or PVAP and optimised with results in acid resistance (EC-PF8 required 2 hr to release in 0.1N HCl, 69.85% at 45 min at pH 6.8 (better than marketed Aciban 69.85% at 45 min at pH 6.8). Stability tests verified the strength of EC-PF8, with 94% or more release and 98.5% assay remaining after 3 months at 40°C/75% relative humidity. Therefore, EC-PF8 is an enhanced formulation that exceeds commercial standards of release kinetics and stability. The enteric-coated formulation, EC-PF8, showed the highest release of 100.16% in 45 min at 6.8 pH phosphate buffer, following the resistance of acids, and across all formulations, EC-PF8 recorded the highest release of the drug in 45 min compared to the rest. The optimized formulation demonstrated adequate gastric protection and rapid drug release under intestinal pH conditions, ensuring improved stability of the acid-labile drug. From a clinical perspective, this approach supports enhanced therapeutic effectiveness by delivering the drug at the intended absorption site. From an industrial standpoint, the formulation strategy using conventional wet granulation and enteric coating techniques provides a reproducible and scalable platform for manufacturing gastro-resistant proton pump inhibitor tablets, highlighting its potential applicability in pharmaceutical production.