Formulation and Evaluation of Paracetamol Matrix Tablet Using Natural Polymer

Oral route is one of the most popular routes of drug delivery due to its ease of administration, patient compliance, least sterility constraints and flexible design of dosage form (Indian Pharmacopoeia).

Tablets: Over 90% of the formulations manufactured today are ingested orally. This shows that this class of formulation in the most popular worldwide and the major attention of the researcher is toward this direction.  With advanced in technology and increase in awareness, toward modification in standard tablets is done to achieve better acceptability as well as bioavailability because of which newer and more efficient tablet dosage forms are being developed. The main reasons behind formulation of different type of the tablets are to create a delivery system that is relatively simple and in expensive to manufacture, provide the dosage form that is convenient from patients perspective and utilize an approach that is unlikely to add complexity during regulatory approval process. To understand each dosage form, tablets here are classified by their route of adrninistration and by the type of drug delivery system they represent within route.

Overview on types and class of tablets:

1. Tablet lngested Orally:

These tablets are meant to be swallowed intact along with sufficient quantity of the potable water. Exception are chewable tablet and oral dispersible tablets. Standard compressed tablets this class includes tablets like, multiple compressed tablets, compression coated tablets, layered tablets, modified released tablets etc.

2. Tablets used in the oral cavity:

The tablets under this group are airned to released active pharmaceutical ingredient in the oral cavity or to provide local action in this region. The tablets under this category avoids first-pass metabolism, decomposition in gastric environrnent, nauseatic sensations and gives rapid onset of action. The tablets fommlated for this region are designed to fit in proper region of oral cavity. This class includes tablets like lozenges and troches, sublingual tablets, buccal tablets, dental eones, oral dispersible tablet etc.

3. Tablets administered by other routes:

These tablets are administered by other route except for the oral cavity and so the drugs are avoided from passing through gastrointestinal tract. These tablets may be inserted into other body cavities or directly placed below the skin to the absorb into systemic circulation from the site of application. This class include tablets vaginal tablets, implants etc.

4. Tablets used to prepare solution:

The tablets under this category are required to be dissolved first in water or other solvent before administration or application. This solution may be for ingestion or parenteral application or for topical use depending upon type of medicament used. This class includes tablets like effervescent tablet, hypodermic tablet etc.

Matrix Tablets:

Definition:

Matrix tablets are the type of tablet which is designed such that it releases it contents regarding first order kineticks or zero order kinetics due to special arrangement and combination of hydrophobic and hydrophilic polymers as an excipient to form a matrix. example of such a matrix tablets are, controlled release tablet, sustained released tablet. these all come under the category of modified release tablet.

MATERIAL AND METHOD:

Preformulation study: Pre-formulation may be described as a phase the research and development process where the formulation scientist characterizes the physical, chemical and mechanical properties of new drug substances, in order to develop stable, safe and effective dosage forms. Ideally the pre-formulation phase begins early in the discovery process such that the appropriate physical and chemical data is available to aid the selection of the new chemical entities that enter the development process. During this evaluation, possible interactions with various inert ingredients intended for use in final dosage form is also considered in the present study. The following data must be considered.

Table 1: Preliminary screening of formulation of sustained release layer of paracetamol using natural, hydrophillic and hydrophobic polymers

Organoleptic property:

Table no 2.: Description of the drug (Paracetamol).

Solubility studies:

An excess quantity of Paracetamol was taken separately and add in 1O ml of different solutions. These solutions were shaken well for few minutes. Then the solubility was observed and observations are shown in the table no.3.2-

Table no 3: Solubility studies of drug in different solvents.

Partition coefficient:

It is a measurement of drug's hydrophilicity and an indication of its ability to cross cell membranes, partition coefficient of Paracetamol was found out by suspending known amount of drug in 1:1 mixture of octanol/water. The concentration of the drug in oil and water was determined through the absorbance of the dilution of the drug

Table no 4 Partition coefficient of drug

Loss on drying studies:

About 1g of the powder was weighted and kept for checking the loss on drying on a moisture sensitive balance at 105°C for 3 minute % loss of moisture was 8%.

pH of the solution:

The pH study was done for the drug by dissolving it in their water as solvent and determining the pH while the help of pH meter. The pH value of clrug has been shown in tableno.3.4.

Table no. 5 pH of drug solution

Melting point:

Melting point of the clrug was determined by the Theil 's Apparatus. It can be performed by filling of the drug in capillary tube and tied this capillary tube at the bottom of thermometer with the help of thread. Now filled Theil's with light liquid paraffin and holded this tube with the help of burette stand than place burner at the bottom of tube, dip the thermometer in this liquid paraffin and the note the point which drug started melting in the capillary. Melting point of drug has been shown in the table no 3.3.

Table no 6 Melting point of drug

Standard calibration curve for Paracetamol:

Preparation of standard solution:

For preparation of standard solution, I Omg of drug was dissolved in IO ml of distilled water (upto IO ml). This is stock solution.

Preparation of sample:

Prepared O.O IN KMn04 solution and O. IN NaOH solution and mixed 5ml of KMn04 of the solution in 5ml of NaOH solution. Withdrawn O.I, 0.2,0.3,0.4,0.5 ml from stock solution and added 5ml of mixture of KMn04 in NaOH solution and up to volume upto I Oml with the help of distilled water. Drug solution was scanned on UV Visible spectrophotometer to obtain A.max of the drug which was found to be 6IO nm. Absorbance of different aliquots was measured at the A.max specific for that drug on UV Visible spectrophotometer (Model: UV - 1700 Shimadzu, Japan) at 6I Onm. Linear regressed calibration curve was constructed which has been represented in graph given table no 3.6.

Table no 7: Absorbance of different aliquots of Paracetamol at 610 nm