Development and Evaluation of Effervescent Tablets with Caffeine, Green Tea, and Lemon Extract

Effervescent tablets are increasingly utilized in pharmaceuticals due to their convenience, rapid dissolution, and improved bioavailability. This study explores the development of a tablet combining caffeine, green tea, and lemon extracts, which offers therapeutic and health benefits.

       
           
       
    
The effervescence in these tablets, facilitated by acid-base reactions, enhances solubility and patient compliance, particularly for populations with difficulty swallowing conventional tablets.

3.1 Background

Oral drug delivery remains the most accessible route of administration, but conventional tablets often exhibit limitations such as inconsistent absorption and poor palatability. Effervescent formulations, however, provide a solution by dissolving rapidly and masking the taste of active ingredients through carbon dioxide release. This formulation, particularly optimized in Batch F2, was developed to deliver caffeine, green tea, and lemon extracts effectively and to offer additional health benefits due to the antioxidant properties of these botanicals.

4. Literature Review

Effervescent tablets have been widely studied for their advantages in enhancing drug absorption and patient compliance. Studies by Vanhere et al. (2023) reported improved drug solubility and taste-masking benefits using effervescent formulations that combine acids with bicarbonates. Additionally, Gillani et al. (2023) found that effervescent formulations significantly improve bioavailability, particularly for compounds with limited water solubility . These studies highlight the potential for effervescent tablets in both therapeutic and nutraceutical applications, supporting the viability of a caffeine-green tea-lemon extract formulation.

MATERIALS AND METHODS

5.1 Chemicals

The following analytical-grade chemicals were used:

Active Ingredients:

• Caffeine
• Green Tea Extract
• Lemon Extract

Excipients and Effervescent Agents:

• Citric Acid
• Tartaric Acid
• Sodium Bicarbonate
• Sodium Starch Glycolate (SSG)
• Crosscarmellose Sodium (CCS)
• Starch
• Methyl Paraben
• Propyl Paraben
• Talc
• Magnesium Stearate

5.2 Preformulation Study

Preformulation studies ensured the compatibility and stability of the selected ingredients before tablet formulation.

Organoleptic Properties:

Color: White for caffeine; green to brownish-green for green tea; off-white to light yellow for lemon extract.

Taste and Odor: Caffeine is bitter and odorless; green tea is bitter with a grassy aroma; lemon extract has a strong citrus aroma and sour taste.

Flow Properties:

Bulk and Tapped Density: Evaluated to ensure optimal flow and compaction.

Carr’s Index and Hausner’s Ratio: Used to assess the powder’s flow characteristics.

Flow Properties of Ingredients

Stability Studies: Conducted to observe the color, odor, and moisture sensitivity over time.

5.3 PREPARATION OF EFFERVESCENT TABLET

This is a detailed process for preparing a tablet formulation containing caffeine, green tea extract, lemon extract, starch, methylparaben, propylparaben, citric acid, tartaric acid, sodium bicarbonate, sodium starch glycolate (SSG), and crosscarmellose sodium (CCS).

Here's a summary of the functions of each ingredient and step:

Ingredients:

•  Caffeine: active ingredient- 50 mg

•  Green Tea Extract: active ingredient- 50 mg

•  Lemon Extract: active ingredient- 50 mg

•  Starch: filler and binder- 20 mg

•  Methyl paraben and Propyl paraben: preservatives- 1 mg & 1 mg

•  Talc and Magnesium Stearate: lubricants- 5mg & 10 mg

•  Sodium Bicarbonate: effervescent agent- 120 mg

•  Sodium Starch Glycolate (SSG) and Crosscarmellose Sodium (CCS):

superdisintegrants- 10 mg & 5 mg

•  Citric Acid and Tartaric Acid: acidulants- 30 mg & 20 mg

Step-by-Step Preparation Process:

1. Preparing Blend:

•  Weigh and accurately mix caffeine, green tea extract, lemon extract, starch, methylparaben,

and propylparaben in a blender.

•  Function: This blend ensures uniform distribution of the active ingredients

(caffeine,green tea extract, and lemon extract) along with starch and preservatives

(methylparaben and propylparaben), ensuring consistent dosage and stability of the tablet.

2. Granulation:

•  Dissolve citric acid and tartaric acid in water to form a solution.

•  Function: Citric acid and tartaric acid serve as acidulants. Their solution will facilitate

the effervescent reaction when combined with sodium bicarbonate, resulting in the

release of carbon dioxide gas, which helps in disintegration and dissolution of the tablet.

•  Add the solution to the blend prepared in step 1 while continuously blending to form a wet

mass.

•  Function: The wet mass facilitates uniform distribution of the acids throughout the

blend, ensuring efficient effervescence upon tablet dissolution.

•  Pass the wet mass through a suitable mesh to obtain granules.

•  Function: This step helps in breaking down the wet mass into granules of uniform size,

facilitating drying and subsequent processing.

3. Formulation:

•  After drying, add talc, magnesium stearate, sodium bicarbonate, sodium starch glycolate

(SSG), and crosscarmellose sodium (CCS) to the granules.

•  Function: Talc and magnesium stearate act as lubricants, preventing sticking of the

tablet material during compression. Sodium bicarbonate serves as the effervescent agent,

reacting with the acids to produce carbon dioxide gas. Sodium starch glycolate (SSG) and

crosscarmellose sodium (CCS) act as superdisintegrants, promoting rapid disintegration of

the tablet for optimal absorption of the active ingredients.

4. Compression machine :

•  Compress the blend into tablets of 250 mg each using a suitable tablet compression

•  Function: Compression forms the final tablet dosage form, ensuring accurate dosage

and physical integrity for handling and administration.

5. Packaging:

•  After compression, inspect the tablets for any defects.

•  Function: Inspection ensures the quality and integrity of the tablets before packaging.

•  Pack the tablets in suitable packaging material to protect them from environmental factors.

•  Function: Packaging preserves the stability and quality of the tablets during storage

and transportation.

RESULTS AND DISCUSSION

6.1 EVALUATION OF EFFERVESCENT TABLET

The effervescent tablets containing caffeine, green tea extract, and lemon extract were evaluated across multiple parameters to ensure quality, consistency, and functionality. Batch F2 emerged as the optimized batch based on favorable results in various tests, which are detailed below.

1. Organoleptic Properties                                                                                                              Shape and Color: Tablets were round with a light green hue, reflecting the natural colors of green tea and lemon extract. This appearance is visually appealing and suggests a natural, health-oriented product.                                                                                                                   Texture: The tablets had a smooth surface with no roughness or irregularities, indicating good manufacturing quality.                                                                                                                   Odor: A pleasant blend of citrus and herbal notes was observed, enhancing the sensory experience and masking any bitter notes from caffeine.

2. Flow Properties of Effervescent Powder

Flow properties of the powder blend are crucial for ensuring uniformity during tablet compression. Batch F2 showed excellent flowability, as evidenced by its angle of repose, Carr’s index, and Hausner’s ratio:

3. Thickness Test

Thickness uniformity is critical to maintaining consistent dosing and appearance across tablets. Using Vernier calipers, the thickness of each formulation was measured, with Batch F2 meeting ideal standards:

4. Weight Variation Test

Uniform weight is essential for dosage accuracy. The weight variation test for Batch F2 showed consistency within acceptable pharmacopeial limits:

5. Hardness Test

The hardness of the tablet is a critical factor in ensuring structural integrity during handling. Batch F2 displayed suitable hardness:

With a hardness of 2.23 Kg/cm?2;, Batch F2 tablets maintained sufficient resilience while enabling rapid disintegration, making it ideal for effervescent formulations.

6. Friability Test

The friability test measures the tablet’s resistance to breaking or crumbling. Batch F2 exhibited acceptable friability within the USP limit of 1%.

Batch F2 showed friability of 0.64%, which is within the acceptable range, indicating that the tablets can withstand handling and transport without significant damage.

7. Dissolution Test

The dissolution rate is a key indicator of the tablet’s ability to release active ingredients quickly, which is crucial for bioavailability. Batch F2 demonstrated the fastest dissolution rate:

With a dissolution time of 76 seconds, Batch F2 was optimized for quick release, confirming its effectiveness as an immediate-release effervescent tablet.

8. Disintegration Test

Disintegration time is essential to ensure the tablet breaks down effectively in water, releasing active ingredients for absorption. Batch F2 showed an optimal disintegration time:

With a disintegration time of 117 seconds, Batch F2 meets the requirements for fast dissolution, enhancing patient convenience and adherence.

9. Measurement of CO? Content

The CO? content reflects the effervescence strength of the tablet. Batch F2 produced an optimal amount of CO?, contributing to rapid disintegration and a pleasant sensory experience.

With a CO? content of 0.29 g, Batch F2 provides an ideal effervescence level, ensuring a satisfying consumer experience.

10. pH Test

The pH of the effervescent tablet solution was measured to ensure compatibility with the digestive system. Batch F2 showed a suitable pH:

With a pH of 5.9, Batch F2 is slightly acidic, enhancing the tablet’s taste and ensuring quick absorption in the gastrointestinal tract.

11. Stability Test for Optimized Batch (F2)

Stability testing was conducted on Batch F2 at specific temperature and humidity conditions over six months to ensure long-term durability.