Formulation And Evaluation of Ayurvedic Solid Dosage Form of Vati

Vati (solid dosage form tablet) is an important drug delivery system in Ayurveda. Acharya Sharagandhar, in 13th century A. D. was first person who explained in detail about Bhaishajya Kalpana (Bhashaijya means medicine; Kalpana means dosage form) in Sharangadhara Samhita. He explained various Kalpana and in one of the chapters he explained about Vati. Ayurveda, the ancient system of medicine, uses various formulations to deliver therapeutic benefits and Vati Kalpana (tablet or pill form) is one of the most important solid dosage forms. It is prepared by grinding herbal or herbo-mineral ingredients into a fine powder, mixing them with binding agents like honey, jaggery or medicinal decoctions and shaping them into tablets. Vati is widely preferred due to its ease of administration, longer shelf life and accurate dosage. Unlike liquid formulations, Vati is convenient for storage and transport, making it a popular choice in Ayurvedic treatment. The preparation process ensures that the medicinal properties of the ingredients are retained while enhancing their stability and bioavailability. [4,5]

With growing interest in traditional medicine, scientific standardization and quality control of Vati formulations have become crucial. Research continues to validate their efficacy, ensuring they meet modern safety and therapeutic standards while preserving the essence of Ayurveda. It is fact that the success of treatment depends mostly upon the quality of drugs, for that medical research work gives emphasis to drug research. Similarly in Ayurveda Pharmacy also several Acharyas has been added or modified the different formulations or preparations according to their own experiences from time to time without violating the basic principles, to find out the most potent drug to prepared different formulations of herbal, Herbo-mineral compounds in various form. To keep the medicine potent for long time, to prepared the medicine for easy administration and also quick action is taken into consideration. [9,11] In the Ayurvedic field of practice through several types of Kalpanas are being used presently, Vati Kalpana plays an important role in pharmaceutics of Ayurveda, owing to many advantages like easy administration, palatability, convenient form for dispensing and transportation. In Ayurvedic pharmaceutics, Vati Kalpana is one of the most admired and prescribed formulation due to its easy Administration, palatability, better shelflife and convenience in its dispensing & transport. Powdered raw drugs (Herbal or Herbo-mineral) are triturated along with water, certain Swarasa, Gomutra, Godugdha, jaggery, guggulu or honey as binding agents and then molded into spherical form by hands or machine, the final product is known as Vati, Vatak or Gutika. Binding agents used also have their own medicinal values. [1] Present work mainly focuses on the details of this ancient formulations i.e., Vati Kalpana as transcript in Ayurveda. “Kalpana means Yojna” According to Acharya Vagbhatta Vati Kalpana is a derived form of Kalka Kalpanas. Panchvidha kasaya kalpana are the Fundamental preparation. All other formulations are derived from Panchvidha kasaya Kalpana. [3]

Type of Vati

In the Ayurvedic Pharmaceutical text two types of Vati preparation methods are mentioned Sagnisadhya Vati and Anagnisadhya Vati.

Sagnisadhya Vati (Heat Processed Vati)

Preparation: These Vati formulations involve the use of heat during their preparation. Process: Ingredients like jaggery, sugar or guggulu are melted and mixed with powdered herbs before shaping them into pills.

Examples

Jaggery Vati (contains jaggery resin, prepared using heat)

Parpati Vati (contains purified metals and minerals processed with heat)

Advantages

• • • • Enhances binding of ingredients.
      • Increases shelf life and stability of the medicine.
      • Suitable for formulations requiring herbo-mineral or resin based ingredients.

Anagnisadhya Vati (Non Heat Processed Vati) Preparation: These Vati are prepared without using heat.

Process: Medicinal powders are triturated with liquids like Swarasa (fresh juice), Kwatha (decoctions) or honey, then rolled into pills.

Examples

Triphala Vati (prepared by mixing Triphala powder with decoction and rolling into pills) Chandraprabha Vati (herbal mineral tablet prepared without heat)

Advantages

• Preserves therapeutic potency of heat sensitive ingredients.
• Simple preparation method.

Often used for delicate herbal formulations that do not require heat processing.

MATERIALS

Preparation of Herbal Ingredients

1. 1. Drying

Purpose: Drying the herbal ingredients is crucial to prevent moisture content that can cause microbial growth, spoilage or uneven texture during compression.

Process

• Selection of Raw Materials: Start by selecting fresh, highquality Haritaki, Bibhitaki and Amalaki fruits. Ensure they are clean and free from contaminants like dirt, molds or foreign materials.
• Sun Drying or Shade Drying: The ingredients should be dried carefully. Shadedrying is the preferred method to retain the active compounds in the herbs. Place the raw fruits in a wellventilated area away from direct sunlight to prevent the degradation of bioactive components like tannins and antioxidants, especially Vitamin C in Amalaki. Sundrying may cause heat degradation.
• Drying Duration: The fruits need to be dried for several days until they become crisp and break easily when squeezed. Ensure that the herbs retain their essential properties and are not overheated, as excessive heat can break down valuable phytochemicals.
  2. Grinding

Purpose: Grinding the dried herbs into a fine powder helps in uniform mixing and compression during tablet formation. A fine powder also ensures faster absorption in the body. Process: Use a grinder or impact mill to break down the dried ingredients into a fine powder. An impact mill, which uses highspeed rotating blades to shatter the plant material, is more efficient for grinding herbs with tough exteriors like Haritaki and Bibhitaki. The grinding process should be done in batches to prevent overheating of the powders, as excessive heat can destroy the active principles in the herbs.

Grinding Speed: The grinding speed should be controlled to avoid excessive friction that could heat the powder. A fine powder will aid in compressing and ensure uniformity in the final Vati.

1. 3. Sieving

Purpose: Sieving ensures that the particle size of the powder is uniform, which is important for consistency in tablet hardness, dissolution and uniform distribution of active ingredients. Process: After grinding, the powder must be sieved through an 80 mesh sieve to remove any coarse particles. The sieve size should be consistent, as larger particles can result in uneven compression, leading to variable tablet strength, dissolution time and content uniformity.

2. Jaggery Preparation
   1. Weighing

Purpose: Accurate weighing ensures the correct proportion of jaggery to herbal powders, which is crucial for the consistency of the Vati.

Process: Weigh exactly 30 grams of jaggery. The use of jaggery in this formulation serves as a natural binder and sweetener. It helps in binding the herbal powder into a cohesive paste and gives the Vati its characteristic taste and medicinal properties.

1. 2. Melting

Purpose: Melting jaggery ensures that it mixes uniformly with the herbal powders to create a consistent doughlike mass.

Process: Heat the jaggery on low heat to ensure it melts without burning. Jaggery has a delicate consistency and burns easily, which can result in a bitter taste and degrade its medicinal properties. The melted jaggery should be smooth and free from any crystallized chunks. Stir the jaggery gently as it melts to achieve a smooth, liquid consistency.

Optimal Temperature: Maintain a temperature of approximately 60–70°C to prevent overheating. Excessive heat could cause caramelization, which may affect the flavor and medicinal efficacy.

1. 3. Cooling

Purpose: Cooling the melted jaggery helps achieve the right consistency for blending with herbal powders.

Process: Allow the melted jaggery to cool for a few minutes before adding it to the powdered herbs. The temperature should be just enough to be easily handled, around 40–50°C, so it can be mixed thoroughly with the powders without causing the mass to become too sticky or too dry.

3. Blending the Ingredients
   1. Mixing

Purpose: Mixing the powdered herbs with jaggery ensures uniform distribution of all ingredients and helps form a doughlike consistency for easy compression.

Process: In a large, clean mixing bowl or industrial mixer, combine the Haritaki, Bibhitaki and Amalaki powders. Gradually add the melted jaggery to the powder, mixing continuously. The jaggery acts as a binder and helps hold the herbal powders together. If needed, a small amount of herbal decoction or water may be added to help create a smooth paste. However, the goal is to avoid excessive moisture, as too much water can affect the tablet's hardness and shelf life.

1. 2. Binding

Purpose: Binding is the process of ensuring that the herbal powders stick together in a cohesive mass, which is essential for forming solid and stable tablets.

Process: As the jaggery is added, knead the mixture thoroughly by hand or using a mechanical mixer until it forms a cohesive, doughlike texture. The dough should not be too wet or too dry; it should be firm enough to retain its shape but pliable enough to be compressed.

If needed, add magnesium stearate (a lubricant) or colloidal silica to improve the flow of the mixture and prevent it from sticking to the tablet press.

If you desire a disintegrating agent, small amounts of starch can be added to ensure that the tablets disintegrate properly once ingested.

4. Tablet Compression
   1. Punch Compression Setup

Purpose: Punch compression is used to compress the herbal jaggery mass into uniform tablets. This process is essential to ensure the Vatis are of consistent weight, size and hardness.

Process:

• Loading: Once the herbal jaggery paste is ready, load it into the hopper of the punch compression machine (tablet press). The paste should be smooth and free from air pockets.
• Punch and Die Selection: Select the correct punch and die sizes according to the desired tablet size (usually 250500 mg per Vati). Ensure that the punch size allows for easy compression without overcompressing, which can affect tablet integrity.
• Compression Force: Adjust the compression force on the tablet press. The force should be sufficient to bind the mixture together but not so high as to cause the tablets to become too hard and brittle.
• Uniformity: Ensure the Vatis are of uniform size and weight, which is essential for consistent dosage. Compression speed should be slow initially to ensure even filling, followed by faster compression to increase production efficiency.

5. Drying
   1. Drying Oven

Purpose: Drying the tablets ensures they maintain stability, prevent microbial growth and achieve the correct hardness for storage and handling.

Process: After compression, the tablets should be dried to remove any remaining moisture. Place the tablets in a drying oven at a low temperature (4050°C) to prevent overheating.

Drying Duration: The drying process typically takes 12–24 hours depending on the moisture content.

Moisture Content: Use a moisture analyzer to check that the moisture content is below 8%, with an ideal range of 3–5%. If the moisture content is too high, the tablets can become prone to microbial contamination and spoilage.

6. Storage

Purpose: Proper storage ensures the shelflife of the tablets, preserving their potency and preventing degradation.

Process: Once the tablets are dry, store them in airtight containers to protect them from humidity, light and contaminants. Keep the storage containers in a cool, dry place, away from direct sunlight and moisture. The ideal storage temperature is 2025°C. Ensure that the storage area is wellventilated and free from pests to maintain the quality of the Vatis.

Table No. 3 - Formulation Table

Fig.No.5 - vati (tablet)

EVALUATION

1. Preformulation study

Preformulation studies are conducted to evaluate the physical and chemical properties of raw materials before formulation. For the Vati (with Haritaki, Bibhitaki, Amla and Jaggery), the following parameters are assessed:

1. 1. Organoleptic properties

1. 2. Angle of repose Procedure
      1. Fix a funnel at a set height (e.g., 6 cm) above a flat surface.
      2. Allow the powdered blend to flow freely through the funnel, forming a conical pile on the surface.
      3. Measure the height (h) of the pile and the radius (r) of the base.
      4. Calculate the angle of repose using the formula:

θ=tan-1 (height/radius)

Observation Table

Table No. 5 - Angle of Repose

Average Angle of Repose

θavg = {31.7 + 31.3 + 31.9}/{3} = 31.63°

Result

The average angle of repose of the powder blend was found to be 31.63°, which indicates passable to fair flowability.

1. 3. Loss of drying Procedure
1. Weigh 2–5 g of the powdered Vati sample.
2. Dry in a hot air oven at 105°C for 2 hours.
3. Cool in a desiccator and reweigh. Calculate LOD using:

LOD (%) = {Initial weight Final weight}/{Initial weight} 100

Observation Table

Table No. 6 - Loss of drying

The Loss on Drying of the Vati was found to be 4.80%, which is within acceptable limits, indicating suitable moisture content for stability.

1. 4. Compressibility testing ( Carr’s Index )

Principle

The difference between bulk density (loose powder) and tapped density (after tapping) gives an estimate of how compressible the powder is. A lower index indicates better flowability and compressibility.

Procedure

1. Weigh accurately about 10 g of the powdered Vati formulation.
2. Gently fill into a 10 mL graduated cylinder without compacting and note the volume (V?) this gives bulk volume.
3. Tap the cylinder 100 times and record the new volume (Vt) – this gives tapped volume.
4. Calculate:
   • Bulk Density (BD) = Weight / V?
   • Tapped Density (TD) = Weight / Vt
   • Carr’s Index (%) = {TD BD}/{TD} 100

Observation Table

Table No. 7 - Carr’s Index

Result: The Carr’s Index of the Vati powder blend was found to be 18.03%, indicating fair to good flowability and acceptable compressibility for manual or mechanical preparation of Vati.

E. Hausner Ratio

Formula:

Hausner Ratio = Tapped Density/Bulk Density

Procedure

1. Weigh 10 g of the powdered blend.
2. Transfer it into a 10 mL measuring cylinder and record the bulk volume (V?).
3. Tap the cylinder until a constant volume is reached and record the tapped volume (Vt).
4. Calculate:
   •  Bulk Density = Weight / V?
   • Tapped Density = Weight / Vt
   • Hausner Ratio = Tapped Density / Bulk Density

Observation Table

Table No. 8 - Hausner Ratio

Result

The Hausner Ratio of the Vati powder blend was found to be 1.22, indicating fair flowability.

F. solubility profile

Procedure

1. 1. 1. Weigh 100 mg of powdered Vati.
      2. Add it to 10 mL of each solvent in separate test tubes.
      3. Shake vigorously for 15 minutes or stir using a magnetic stirrer.
      4. Allow to stand and observe for dissolution or precipitation.
      5. Note the degree of solubility visually.

Observation Table

Table No. 9 - Solubility profile

Result

The Vati formulation was found to be soluble in ethanol and methanol, partially soluble in water and insoluble in chloroform, indicating that the formulation contains both hydrophilic and lipophilic phytoconstituents.

G. pH determination

Procedure

1. 1. 1. Weigh 1 g of powdered Vati.
      2. Disperse it in 100 mL of distilled water in a beaker.
      3. Stir the solution for 15–20 minutes to ensure uniform dispersion.
      4. Filter the solution if necessary.
      5. Insert the calibrated pH electrode into the solution and record the pH.

Observation

Table No. 10 – pH Value

Result

The pH of the aqueous solution of the Vati formulation was found to be 4.8, indicating a mildly acidic nature.

2. Postcompression Assessment of Powder Blend

A. Hardness Test

Procedure

1. 1. 1. Six vatis were selected randomly.
      2. Each vati was placed between the anvil and plunger of the Monsanto Hardness Tester.
      3. Force was applied gradually until the vati cracked or broke.
      4. The force required to break each vati was noted.
      5. The average hardness was calculated from the six readings.

Procedure

1. 1. 6. Weigh 1 g of powdered Vati.
      7. Disperse it in 100 mL of distilled water in a beaker.
      8. Stir the solution for 15–20 minutes to ensure uniform dispersion.
      9. Filter the solution if necessary.
      10. Insert the calibrated pH electrode into the solution and record the pH.

Observation

Table No. 10 – pH Value

Result

The pH of the aqueous solution of the Vati formulation was found to be 4.8, indicating a mildly acidic nature.

2. Postcompression Assessment of Powder Blend

A.Hardness Test

To assess the mechanical strength of Vati and ensure it can withstand mechanical stress during handling and transportation.

Procedure

1. 1. 6. Six vatis were selected randomly.
      7. Each vati was placed between the anvil and plunger of the Monsanto Hardness Tester.
      8. Force was applied gradually until the vati cracked or broke.
      9. The force required to break each vati was noted.
      10. The average hardness was calculated from the six readings.

Observation Table

Table No. 11 – Hardness Test

B. Friability test

Procedure

1. Weigh 10 vatis collectively and note the initial weight (W?).
2. Place the vatis in the friabilator.
3. Rotate the drum at 25 rpm for 4 minutes (total 100 revolutions).
4. Remove the vatis, dust them gently with a brush and weigh again to obtain the final weight (W?).
5. Calculate the percentage friability using the formula:

Observation Table

Table No. 12 - Friability test

C. Weight Variation Test

Procedure

1. Select 10 vatis randomly.
2. Weigh each vati one by one using a digital balance.
3. Calculate the average weight.
4. Compare the individual weights with the average to ensure they are close.
5. As per standard, if the vati weighs more than 250 mg, the variation should not be more than ±5%.

Observation Table

Table No. 13 - Weight Variation Test

Disintegration Time Test

Procedure

1. Set up the disintegration test apparatus with 6 openended glass tubes and wire mesh at the bottom.
2. Fill the beaker of the apparatus with distilled water (or simulated gastric fluid), ensuring the temperature remains at 37 ± 2°C throughout the test.
3. Place one vati in each of the 6 tubes.
4. Start the apparatus so that the tubes move up and down in the fluid.
5. Simultaneously, start the stopwatch.
6. Observe each vati and note the time taken for complete disintegration, which is when no solid residue remains, except for fragments of the coating or insoluble substances.
7. Record the time for each vati and calculate the average disintegration time.

Observation Table

Table No. 14 - Disintegration Time Test

E. Dissolution Test

1. Preparation

Heat 900 ml of the dissolution medium to 37 ± 0.5°C to simulate body temperature. Place the medium in a beaker or use the dissolution apparatus.

2. Sample Placement

Place one vati into the dissolution medium.

Begin gentle stirring (50 rpm if using apparatus or manual stirring at regular intervals).

Sampling

At time intervals of 5, 10, 15, 30, 45 and 60 minutes, observe the solution visually.

Note the color change, turbidity and breakdown of the vati. If needed, collect small samples in test tubes to observe how well the herbal ingredients have dissolved.

Repeat the same process for 6 vatis to ensure uniformity.

Observation Table (Visual Method)

Table No. 15 - Dissolution Test

Organoleptic Evaluation

Organoleptic properties are essential in Ayurvedic formulations to assess the quality and consumer acceptability of the final product.

Table No. 16 - Organoleptic Evaluation

The dark brown color was attributed to the combination of Triphala powders and jaggery. The natural aroma and taste remained intact, indicating that the method of preparation did not degrade the phytoconstituents. The addition of jaggery also masked the strong astringent taste of Triphala, improving patient compliance.

1. Physical Evaluation Parameters

A number of quality control tests were performed to ensure the pharmaceutical acceptability of the Vati.

Table No. 17 - Physical Evaluation Parameters