Fast dissolving tablets (FDTs), also known as orally disintegrating tablets (ODTs) or mouth-dissolving tablets (MDTs), are solid dosage forms designed to disintegrate or dissolve quickly in the mouth without the need for water or chewing. These tablets offer several advantages over conventional forms, particularly for individuals who may have difficulty swallowing, such as paediatric, geriatric, or dysphagic patients. Below is an overview of fast dissolving tablets:

Fast dissolving tablets typically consist of active pharmaceutical ingredients (APIs) along with excipients such as superdisintegrants, fillers, sweeteners, and flavouring agents. Superdisintegrants like Crospovidone, Croscarmellose sodium, and sodium starch glycolate are essential for ensuring rapid disintegration.

A gift sample of Naproxen Sodium was provided by Aarti Drugs Pvt. Ltd., Tarapur (Boisar), Maharashtra, India. Croscarmellose and Aspartame were obtained as gift samples from Stallion Lab Pvt. Ltd., Bawla, Gujarat. Additional excipients, including Sodium Starch Glycolate, Crospovidone, Mannitol, Sodium Lauryl Sulfate, and Microcrystalline Cellulose, were gifted by Aura Nutraceuticals Ltd., Budasan, and Gujarat.

Naproxen Sodium samples were procured from Aarti Drugs Pvt. Ltd. and their identity was confirmed through UV-visible wavelength scanning, High-Performance Liquid Chromatography (HPLC), and Fourier Transform Infrared (FT-IR) spectroscopy.

Pre-compression parameters, including bulk density, tap density, Carr’s index, Hausner ratio, and angle of repose, were evaluated for the drug. The tablets were formulated using the direct compression technique.

The compatibility between Naproxen Sodium and excipients was assessed by storing the mixture under different environmental conditions for one month.

The tablets were characterized for free and entrapped Naproxen Sodium content using a UV-spectrophotometric method.

The tablets were evaluated for several parameters, including weight variation, thickness, hardness, friability, drug content, and wetting time.

Disintegration time and dissolution studies were carried out to assess the release profile of Naproxen Sodium from the tablets.

The stability of the tablets was examined over one month at different temperatures and humidity levels. 6, 7, 8, 9, 10

Gift Sample of Naproxen Sodium was obtained from Aarti Drug Pvt. Ltd. Tarapur (Bhoisar), Maharashtra, India. The samples' identities were confirmed via UV-visible wavelength scan and FT-IR spectra. FT-IR spectra were recorded, and the UV-visible spectra of Naproxen Sodium were recorded using methanol and water as solvents on a Shimadzu 1900 instrument.

The UV-Visible spectra of were recorded using methanol as solvent were recorded using water as solvent on Shimadzu Instrument. Naproxen Sodium typically exhibits its maximum absorbance at around 331 nanometers (nm), indicating that it absorbs light most strongly at this wavelength. This characteristic absorption peak is often used for the quantitative analysis of Naproxen Sodium in pharmaceutical formulations and research studies.

The HPLC analysis were recorded using methanol as solvent were recorded using methanol as solvent on Agilent 1100 series Instrument. Naproxen Sodium typically exhibits its maximum absorbance at around 228 nanometers (nm),

The Fourier-transform infrared (FT-IR) spectrum of Naproxen Sodium typically shows characteristic peaks corresponding to functional groups present in the molecule. Some prominent peaks in the FT-IR spectrum of Naproxen Sodium. Interpreting the FT-IR spectrum involves matching peaks with known vibrational frequencies to identify specific functional groups in the molecule shown in Figure 1, Figure 2, Figure 3.

The UV-Visible spectra of Naproxen Sodium were recorded using methanol and water as solvents on a Shimadzu instrument. Naproxen Sodium typically exhibits its maximum absorbance around 331 nanometers (nm), which is used for the quantitative analysis of the drug in pharmaceutical formulations and research studies.

The HPLC analysis was conducted using methanol as the solvent on an Agilent 1100 series instrument, where Naproxen Sodium shows maximum absorbance at approximately 228 nanometers (nm).

The Fourier-transform infrared (FT-IR) spectrum of Naproxen Sodium displays characteristic peaks that correspond to the functional groups in the molecule. Interpreting the FT-IR spectrum involves identifying specific functional groups by matching the peaks with known vibrational frequencies, as shown in Figure 1, Figure 2, Figure 3. 11, 12, 13, 14, 15

Evaluation of tablet: Evaluation parameter:

Appearance of Tablet: Color: Uniform white. Odor: No unusual odors. Surface Texture: Smooth, free from cracks or roughness.

Particles: No visible particles or foreign matter.

Size and Shape of Tablet: Size: Uniform within specified range. Shape: Consistent, as per design (round or oval).

Uniformity of Weight: Uniformity: Consistent appearance with no significant deviations in color, shape, texture, or size.

Thickness and Diameter: Ensures consistent dosing, handling, packaging, and administration.

Hardness (Crushing Strength): Measured in kilograms or Newton’s. Ensures tablets withstand mechanical stress and remain intact until use.

Friability Test: Low friability ensures tablets remain intact during handling and transportation, minimizing dose variability.

Wetting Time: Indicates how quickly the tablet absorbs saliva and starts to disintegrate, ensuring fast onset of action and better patient compliance.

Disintegration Time: Measures how quickly the tablet breaks down in the mouth, ideally within a few seconds for rapid drug release and absorption.

In-Vitro dissolution studies: In vitro dissolution studies for Naproxen Sodium Fast Dissolving Tablets was carried out using USP paddle method at 50 rpm in 900 ml of phosphate buffer pH 6.8 as dissolution media, maintained at 37±0.5°C. 5 ml aliquot of the solution was withdrawn from the dissolution apparatus after suitable time intervals, and the samples were replaced with fresh dissolution medium. Absorbance of these solutions was measured at 331 nm using a Shimadzu UV- Shimadzu 1900 UV/VIS spectrophotometer.

Table 2

Sr. no.	Concentration (μg/ml)	Absorbance (331 nm)
1.	0	0
2.	5	0.11
3.	10	0.22
4.	15	0.34
5.	20	0.45
6.	25	0.55
7.	30	0.67

Each data represents Mean ± SD (n=3)

Formulation F6 stands out as the most suitable option for the development of Naproxen Sodium Fast Dissolving Tablets due to its optimized superdisintegrants concentration, proper diluents content, consistent drug dosage, uniform tablet weight, effective lubrication, and proper manufacturing techniques.

To plan experiments efficiently, statistical techniques such as factorial design, response surface methodology, or Taguchi methods are utilized. Factors are systematically varied within predetermined ranges, and experiments are conducted at selected combinations of factor levels.

Based on the Design of Experiments (DOE), formulation F9 appears to be the most promising among the provided formulations for several reasons:

Overall, formulation F7 stands out as the most suitable option for the intended purpose based on the analysis, balancing disintegration properties, tablet composition, and simplicity of formulation. 18, 19, 20

Based on the provided table, formulation F9 appears to be the most suitable formulation for several reasons:

The kinetics of In-vitro drug release was determined by applying the drug release data to various kinetic models such as zero order, first order, Higuchi, Peppas-Korsmeyer and Hixson Crowell. The result obtained were represented in Table 7 and shown in Figure 8. 20, 21, 23

The Naproxen Sodium Fast Dissolving Tablets formulations were analyzed using UV-spectrophotometric methods to quantify both free and entrapped Naproxen Sodium.

Result of determination of Free Naproxen Sodium: Tablets were analyzed for free Naproxen Sodium using a UV-spectrophotometric method at a wavelength of 354 nm against an appropriate blank. Tablets were dissolved in distilled water, and the solution was appropriately diluted to ensure the absorbance fell within the range of the standard curve. The absorbance of the diluted solution was measured at 354 nm using a UV-visible spectrophotometer.

Result of determination of Entrapped Naproxen Sodium: Approximately 200 mg of dried Naproxen Sodium Fast Dissolving Tablets were accurately weighed and dissolved in distilled water. The resulting solution was then appropriately diluted with distilled water to obtain absorbance readings within the range of the standard curve. The absorbance of the diluted solution was measured at 331 nm using a UV-visible spectrophotometer. By employing these methods, both free and entrapped Naproxen Sodium in the Fast-Dissolving Tablets were quantified, providing valuable insights into the formulation's efficacy and ensuring the desired drug release profile is achieved.

Look for characteristic peaks associated with the functional groups present in Naproxen Sodium For:O-H Stretch: Broad peak around 3200-3500 cm^-1 due to the stretching vibration of the O-H bond in the carboxylic acid group. C=O Stretch: Strong, sharp peak around 1700-1720 cm^-1 due to the stretching vibration of the carbonyl group (C=O) in the carboxylic acid. C-H Stretch: Typically observed in the range of 2900-3000 cm^-1, representing the stretching vibration of C-H bonds, mainly from the aromatic rings and methyl groups. These peaks provide diagnostic information about the functional groups present in Naproxen Sodium, aiding in its identification and characterization using FT-IR spectroscopy.

The compatibility study of Naproxen Sodium Fast Dissolving Tablets formulation, where the drug and excipients were mixed in equal proportions and stored under different environmental conditions (40°C/RH 60% and 40°C/RH 75%) for 3month, revealed no interaction between the drug and excipients.

Weekly analysis of the samples for curcumin content using UV-visible spectrophotometer showed consistent levels, indicating stability of the formulation under the tested conditions. Additionally, no significant changes in the physical appearance of the samples were observed throughout the study period.

Furthermore, the FT-IR spectrum recorded for Naproxen Sodium Fast Dissolving Tablets formulation F7 confirmed the absence of any notable interactions between the drug and excipients, supporting the overall compatibility of the formulation. 23, 22, 25, 24

Stability study of Naproxen Sodium Fast Dissolving Tablets formulations for 3 months at different temperatures 4⁰, 25⁰C /RH 60%, and 40⁰C /RH 75% Samples of the formulations stored at various conditions of temperature and humidity were taken out at weekly intervals and the concentration of Naproxen Sodium in these were determined using UV-Visible spectrophotometer. The samples were dissolved in water and suitably diluted to read absorbance against water blank at 331 nm. Formulation was subjected to stability studies at 40 ⁰C ± 2 ⁰C / 75% RH ± 5% for 3 months.

The product was evaluated for following parameters:

Storage condition at 40°C ± 2°C/75 %RH ± 5%.

The stability studies for optimized formulation F7 were carried out based accelerated stability conditions and study of various parameters carried out at 0, 30, 60, 90 days of intervals and the results found satisfactorily and that reveals that the optimized formulation was stable under accelerated condition.

Authors don’t have any conflict of interest.