LIST OF CRITICAL PARAMETERS DURING GRANULATION

 

LIST OF CRITICAL PARAMETERS DURING GRANULATION

During the process of granulation in tablet manufacturing a number of parameters to be considered here some of them listed

   1.      Cleaning of area prior to granulation

   2.      Maintain environmental conditions

   3.      Absence of foreign particles

   4.      Types of binder

   5.      Types of binding (impeller & chopper speed and timing)

   6.      Temperature of drying

   7.      Time of drying

   8.      Loss on drying

   9.      Final granule size

   10.  % compressibility

   11.  Flow of powder

   12.  Ratio of granules

   13.  Lubricants used

   14.  Timing of mixing and lubrication

   15.  Storage conditions of RFC powder.

TYPES OF TABLET TOOLING

Definition of Tablets

Tablets can be defined as Solid Pharmaceutical Dosage form containing drug substances with or without suitable diluent and prepare either by compression or moulding methods.

Tablet Tooling

For this purpose different types of punches are used:

Flat- faced bevel- edged.

Shallow concave (Round/ Capsule shaped)

Standard concave (Round/ Capsule shaped)

Deep concave (Round/ Capsule shaped)

Extra deep.

Modified ball
The basic mechanical unit in all tablet-compression equipment includes a lower punch which fits into a die from the bottom and an upper punch, having a head of the same shape and dimensions, which enters the die cavity from the top after tablet material fills the die cavity.

PROCUREMENT OF TOOLING

While ordering any punch set (From Approved Supplier only), following things should be covered:

1. Drawing for upper/lower punch / die, by the manufacturer as per the specifications given or as per sample punch set.
2. Following details should be given with the purchase order:

•         Total number of set required

•         Type of punch set eg. D/B/BB etc.

•         MOC to be used (HCHC/OHNS)

HCHC: High Carbon High Chromium

OHNS: Oil Hardened non shrinking Steel

• Engraving details; Sr. no., Mfr name, Date of Mfg., Punch size in mm.

•         Special requirements like: Concavity, embossing, chrome plating etc.

Tablet Tooling

There are following types of Tooling available: 

TYPES OF TOOLING

‘B’   -Tooling

‘D’   - Tooling

‘BB’ -Tooling
'DB’ - Tooling

Tablet Tooling Parts

Following definitions for direct terminology for tooling (Punches and dies).

1. Head: The end of the punch that guides it through the cam track of tablet machine during rotation.

2. Head flat (Dwell Flat): The flat area of the head that receives the compression force from rollers (in upper punches) and determines the weight and ejection height (in lower punches).

3. Outside head Angle: The area gets in touch with the roller prior to head flat, while compression.

4. Inside Head Angle:This is the area, which pulls down the lower punches after ejection and lifts the upper punches after compression.

5. Neck: The relived area between the head and barrel, which provides clearance for the cams.

6. Barrel: This area guides the punch (while going up and down) with reference to turret guides.

7. Stem: The area of the punch opposite the head, beginning at the tip and extending to the point where the full diameter of the barrel begins. If the chamfer is present the barrel usually reaches its full diameter just above the chamfer.

8. Tip: This determines size, shape & profile of the tablet.

9. Tip face: This area of punch is where the tablet is formed. Good surface finish is required here to bet quality tablets.

Working length: This distance between bottom of the cup and the head flat is called as working length which determines weight and thickness of the tablet.

10. Overall length: Distance between top of the cup and the head flat.

11. Key Angle: The relationship of the punch key to the tablet shape. The keys position is influenced by the tablet shape, take-off angle, and turret rotation.

12. Domed Heads: Increases the dwell time and hence help to achieve the better tablet hardness.

13. Dwell time: The time punches spends below the pressure roller while rotating in the machine.

WHAT IS TITRATION AND TYPES OF TITRATION

A titration (titrimetry) is a technique where a solution of known concentration is used to determine the concentration of an unknown solution. Typically, the titrant (the know solution) is added from a buret  to a known quantity of the analyte (the unknown solution) until the reaction is complete. Knowing the volume of titrant added allows the determination of the concentration of the unknown. Often, an indicator is used to usually signal the end of the reaction, the endpoint.

Titrations can be classified by the type of reaction. Different types of titration reaction include:

• Acid-base titrations are based on the neutralization reaction between the analyte and an acidic or basic titrant. These most commonly use a pH indicator, a pH meter, or a conductance meter to determine the endpoint.

• Redox titrations are based on an oxidation-reduction reaction between the analyte and titrant. These most commonly use a potentiometer or a redox indicator to determine the endpoint. Frequently either the reactants or the titrant have a colour intense enough that an additional indicator is not needed.

• Complexometric titrations are based on the formation of a complex between the analyte and the titrant. The chelating agent EDTA is very commonly used to titrate metal ions in solution. These titrations generally require specialized indicators that form weaker complexes with the analyte. A common example is Eriochrome Black T for the titration of calcium and magnesium ions.

• A zeta potential titration characterizes heterogeneous systems, such as colloids. Zeta potential plays role of indicator. One of the purposes is determination of iso-electric point when surface charge becomes 0. This can be achieved by changing pH or adding surfactant. Another purpose is determination of the optimum dose of the chemical for flocculation or stabilization

• ·         Gas phase titration

          Gas phase titrations are titrations done in the gas phase, specifically as methods for determining         reactive species by reaction with an excess of some other gas, acting as the titrant. In one common gas phase titration, gaseous ozone is titrated with nitrogen oxide according to the reaction

O₃ + NO → O₂ + NO₂.

After the reaction is complete, the remaining titrant and product are quantified (e.g., by FTIR);  this is used to determine the amount of analyte in the original sample.

Gas phase titration has several advantages over simple spectrophotometry. First, the measurement does not depend on path length, because the same path length is used for the measurement of both the excess titrant and the product. Second, the measurement does not depend on a linear change in absorbance as a function of analyte concentration as defined by the Beer Lambard Law, Third, it is useful for samples containing species which interfere at wavelengths typically used for the analyte.

Disintegration test for Enteric coated tablets

Disintegration test for Enteric coated tablets

The Enteric coated tablets are those tablets which bypass the stomach and get metabolize in the intestine. So firstly the disintegration test done with 0.1 M HCL for 2 hours, tablets should not dissolve in it till 2 hours without disc . Then it must dissolve completely in phosphate buffer solution of 6.8 pH in 1 hour with or without disc.

Preparation of 0.1 M HCL-

Add 8.5 ml of concentrated HCL (37.5%) in 100 ml of water in a volumetric flask with continuously stirring and then make up the volume to 1000 ml with water and stir well.

Preparation of Phosphate buffer solution 6.8pH-

1.       Mixed Phosphate Buffer pH 6.8 As Per IP :- 28.80 gm of disodium hydrogen phosphate and 11.45 gm of Potassium dihydrogen phosphate in 1000 ml with water.

2.       Add 6.8 gm KH2PO4 and about 0.94 gm NaOH in 1000mL Water. Adjust the pH of solution by using dilute Orthophosphoric  acid or NaOH.