Aadhibhagawan College of Pharmacy, Rantham, Thiruvannamalai, Tamil Nadu
Background: Floating tablets enhance drug bioavailability by prolonging gastric residence time. This study investigates the formulation of floating tablets containing silver nanoparticles (AgNPs), focusing on excipient compatibility, preparation methods, and in vitro performance. Methods: Silver nanoparticles, HPMC, PVP, lactose, sodium bicarbonate, magnesium stearate, talc, and ethanol were used to formulate floating tablets. Pre-formulation studies assessed melting point, IR spectra, and physical parameters (angle of repose, bulk density, tapped density, Hausner’s ratio). Compatibility was evaluated by IR spectroscopy. Granulation and compression were followed by evaluations of weight variation, hardness, friability, floating lag time, and dissolution in pH 1.2 buffer at 37°C over 24 hours. Results: Pre-formulation studies showed good flow properties and compressibility. Compatibility studies indicated no significant interactions between drug and excipients. Floating lag time ranged from 30 to 240 seconds, with floating times of 6-9 hours. SNs5 formulation released 80.3% of the drug by 24 hours. Other physical parameters, including hardness and friability, were within acceptable limits. Discussion: The floating tablets exhibited good mechanical strength and controlled drug release. Variations in hardness and friability were due to differences in polymer ratios. The presence of silver nanoparticles did not affect tablet integrity or release. The dissolution studies showed a sustained release, indicating potential benefits in extended drug delivery. Conclusion: The floating tablets containing silver nanoparticles successfully achieved controlled release and prolonged gastric residence time. This formulation has the potential to enhance bioavailability and support targeted therapies using silver nanoparticles.
Nanoparticles are particles that have at least one dimension in the range of 1 to 100 nanometers (nm), where 1 nanometer is one-billionth of a meter (10^-9 m). Due to their small size and unique properties, nanoparticles have become a significant focus of research in fields ranging from medicine and materials science to electronics and environmental applications.
Fig: 1 Silver Nanoparticle
1.1 Types of Nanoparticles:
1.2 Applications of Nanoparticles:
2. DISEASE PROFILE:
2.1 Pathophysiology Of PCOS:
Polycystic Ovary Syndrome Or PCOS is the most common endocrine disorder in women of reproductive age. The syndrome is named after the characteristics cysts which may form on the ovaries, through it is important to note that this is a sign and not then underlying cause of the disorder. A review of the international evidence found that the prevalence of PCOS could be as high as 26% among some populations. Despite is high prevalence, the exact cause of PCOS remains uncertain. The primary characteristics of this syndrome include hypertension, an ovulation, insulin resistance, and neuro endocrine disruption.
Fig: 2 Polycystic Ovary Syndrome
4.1 For Formulation of Floating Tablet:
Silver nanoparticles (AgNP’s), different polymers and excipient like PVP (PVP K30 MW =1.1×106 and PVP K30MW = 5.0×104), ethanol, lactose, hydroxy propyl methyl cellulose, sodium bicarbonate, talc, magnesium stearate.
4.2 Pre Formulation Studies:
The parameters like melting point, IR spectra, angle of repose, bulk density, tapped density, Hausner's ratio were determined as the part of pre formulation studies.
4.3 Drug-Excipient Compatibility Studies:
Compatibility studies were carried out to know the possible interactions between silver nanoparticles and excipients used in the formulation. Physical mixtures of drug and excipients were prepared to study the compatibility using the Infrared spectrophotometer.
4.4 Preparation of Silver Nanoparticles Floating Tablet:
All the ingredients (except glidants and lubricant) were weighed separately, mixed thoroughly in poly bag for 10 minutes to ensure uniform mixing and the mixture was passed through sieve no.60. Granulation was done with a solution of calculated quantity of PVPK30 in sufficient ethanol. The wet mass was passed through sieve no. I2, and dried at 75°C for 2 hours. The dried granules were sized by sieve no. 18 and mixed with magnesium stearate and talc. The blend thus obtained was compressed (8mm diameter, flat punches) using a singles station tablet press machine.
Table: 1 Formulation Table
|
Sr.No |
Ingredients |
SNs1(mg) |
SNs2(mg) |
SNs3(mg) |
SNs4(mg) |
SNs5(mg) |
|
1 |
Silver Nanoparticles |
0.1 |
0.2 |
0.4 |
0.5 |
1 |
|
2 |
HPMC |
50 |
50 |
50 |
50 |
50 |
|
3 |
PVP |
20 |
20 |
20 |
20 |
20 |
|
4 |
Lactose |
20 |
20 |
20 |
20 |
20 |
|
5 |
Sodium Bicarbonate |
20 |
20 |
20 |
20 |
20 |
|
6 |
Magnesium Stearate |
5 |
5 |
5 |
5 |
5 |
|
7 |
Talc |
5 |
5 |
5 |
5 |
5 |
|
|
120.1 |
120.2 |
120.04 |
120.05 |
121 |
|
4.5 Evaluation of Floating Tablets:
4.5.1 Uniformity of weight: Twenty tablets were weighed individually and the average weight was determined. The percentage deviation was calculated and checked for weight variation.
Table: 2 Weight Variation
|
Average weight of tablet (mg) |
% Deviation |
|
80mg or less |
10 |
|
80mg to 250mg |
7.5 |
|
250mg or more |
5 |
4.5.2 Hardness: Hardness or tablet crushing strength (fc), is the force required to break a tablet in a diametric Compression. This compression force was measured using Monsanto tablet hardness tester for all the batches I5. It is expressed in kg/cm².
4.5.3 Thickness: Thickness of tablets is important for uniformity of tablet size. Thickness was measured wing Vernier Calipers on 3 randomly selected samples.
4.5.4 Friability test: Friability is the measure of tablet strength. Roche friabilator was used for testing the friability using the following procedure. Twenty Tablets were weighed accurately and placed in the tumbling apparatus that revolves at 25 pm dropping the tablets through a distance of six inches with each revolution. After 4 minutes, the tables were weighed and the percentage loss in tablet weight was determined using the below given formula.
4.5.5 Floating lag time: The lag time was carried out in beaker containing 250 ml of pH 1.2 buffer solution as a testing medium maintained at 37ºC. The time required for the able to rise to the surface and float was determined as floating lag time in minutes.
4.5.6 Dissolution studies:
The release rate of silver nanoparticles from floating tablets was determined using USP Dissolution Testing Apparatus Il (Paddle type), The dissolution test was performed using 0 ml of pH 1.2 buffer solution, at 37± 0.5ºC and 50 rpm. Aliquot volume was withdrawn from the dissolution apparatus hourly for 12h, and the samples were replaced with fresh dissolution medium. After filtration and suitable dilution the amount of drug release was determined from the calibration curve,
Details of Dissolution Test:
Fig: 3 FTIR of Silver Nanoparticles
Table: 3 Pre-formulation+
|
Formulation |
Angle of repose(Ø) |
Bulk density (gm/cm²) |
Tapped density (gm/cm²) |
Hausner ratio (HR) |
|
SNs1 |
28.1±0.001 |
0.57±0.01 |
0.71±0.04 |
1.24±0.01 |
|
SNs2 |
26.3±0.02 |
0.55±0.02 |
0.67±0.03 |
1.22±0.02 |
|
SNs3 |
27.6±0.03 |
0.55±0.01 |
0.70±0.03 |
1.27±0.03 |
|
SNs4 |
26.9±0.04 |
0.54±0.03 |
0.73±0.03 |
1.35±0.01 |
|
SNs5 |
26.9±0.05 |
0.53±0.04 |
0.67±0.03 |
1.26±0.02 |
Table: 4 post-formulations
|
Sr. No |
Formulations |
Weight Variation |
Friability (%) |
Hardness |
Thickness (mm) |
|
1 |
SNs 1 |
120.1±0.12 |
0.250±0.01 |
4.5±0.2 |
3.0±0.01 |
|
2 |
SNs 2 |
120.2±0.34 |
0.30±0.06 |
5.0±0.1 |
2.9±0.05 |
|
3 |
SNs 3 |
120.05±0.33 |
0.45±0.04 |
4.5±0.12 |
3.1±0.02 |
|
4 |
SNs 4 |
120.5±0.33 |
0.55±0.02 |
5.0±0.16 |
3.2±0.02 |
|
5 |
SNs 5 |
121±0.42 |
0.21±0.03 |
5.5±0.09 |
3.0±0.02 |
5.4 Floating Lag Time:
The floating time is determined in order to assess the time taken by the dosage to float on the top of the dissolution medium, after placing the dosage form in the medium.
Table: 5 Floating Lag Time
|
Sr. No |
Formulations |
Floating Lag Time (Sec) |
Floating Time (Hours) |
|
1 |
SNs 1 |
30 |
8 |
|
2 |
SNs 2 |
120 |
9 |
|
3 |
SNs 3 |
40 |
6 |
|
4 |
SNs 4 |
75 |
6 |
|
5 |
SNs 5 |
240 |
9 |
5.5 Percentage Cumulative Drug Release:
Table: 6 In-vitro Drug Release
|
Time (Hr) |
% Cumulative Drug Release |
||||
|
Formulations |
SNs 1 |
SNs 2 |
SNs 3 |
SNs 4 |
SNs 5 |
|
0 |
0 |
0 |
0 |
0 |
0 |
|
1 |
20.3 |
12.8 |
16.9 |
17.9 |
13.6 |
|
2 |
43.5 |
13.2 |
24.3 |
22.7 |
21.6 |
|
4 |
59.1 |
28.9 |
32.5 |
36.3 |
33.6 |
|
8 |
72.6 |
37.1 |
46.3 |
44.3 |
44.8 |
|
12 |
80.4 |
46.5 |
59.7 |
56.6 |
62.3 |
|
16 |
85.4 |
56.9 |
72.2 |
72.6 |
71.3 |
|
20 |
85.2 |
62.2 |
86.9 |
82.1 |
76.8 |
|
24 |
95.3 |
72.2 |
88.3 |
84.1 |
80.3 |
Fig: 4 Cumulative % Drug Release Curve
DISCUSSION:
Formulation Evaluation: In the pre-formulation phase, the physical properties of the formulation were found to be within acceptable limits. The angle of repose for all batches was less than 30°, indicating good flow properties. Bulk and tapped densities were consistent, and the Hausner's ratio, which reflects the compressibility of the powder, showed that all formulations were suitable for compression.
Drug-Excipient Compatibility: The compatibility studies confirmed that there were no significant interactions between the silver nanoparticles and the excipients, ensuring stability in the final tablet formulation. The IR spectra did not show any new peaks, indicating the absence of undesirable interactions.
Weight Variation, Thickness, Hardness, Friability: The results showed that weight variation, thickness was lying within limits. Because of variation in the compression forces there is a slight variation in hardness of tablet. As the proportion of polymers increases the hardness of tablet was found to increase in case of HPMC K4 and ethyl cellulose tablets HPMC K4 tablets are less harder and thickest tablets. The friability loss was found to be within in the limits in all the formulations. As the amount of polymers increased, the friability of the floating tablet was found to decrease. The results of physical properties of silver nanoparticles floating tablet are given in table and the results revealed that the tables are mechanically strong.
Dissolution studies: Freshly prepare dissolution medium i.e 900ml 0.1N HCl in each dissolution vessel of dissolution paddle apparatus maintained at temperature 37±0.5ºC and rotated at 75 rpm. The tablets of silver nano particles were placed in dissolution medium. About 5ml of dissolution medium was pipetted out for every 15, 30, 60, 120, 240, 480, 960 min and the volume was adjusted using by replacing with 5ml of 0.1N HCl. The above samples i.e 5ml (7 samples) were collected in a volumetric flask and make up the volume to 10 ml with 0.1 N HCl.
Post-formulation evaluations showed that all tablets met the required specifications. The tablets exhibited low friability, indicating their mechanical robustness. The floating lag time ranged from 30 to 240 seconds, and floating time ranged between 6 to 9 hours, indicating the potential for prolonged release. Tablets containing higher amounts of silver nanoparticles exhibited slower release profiles, which could be beneficial for prolonged therapeutic effects. Dissolution studies revealed a slow, sustained release, with the highest cumulative release occurring in formulation SNs1 (95.3% at 24 hours).
The results from this study demonstrate that silver nanoparticle-loaded floating tablets are a promising approach for controlled drug delivery. The tablets achieved mechanical stability, prolonged floating time, and sustained drug release, which are key for improving the bioavailability of silver nanoparticles. The floating system can potentially be used in therapies that require slow and sustained drug release over an extended period.
REFERENCES
K. Thilagavathi, L. Gopi, Dr. V. Kalvimoorthi, Formulation and Evaluation of Silver Nanoparticles Floating Tablets for The Treatment of Polycystic Ovarian Syndrome, Int. J. of Pharm. Sci., 2026, Vol 4, Issue 1, 1-9. https://doi.org/10.5281/zenodo.18113389
10.5281/zenodo.18113389
