Friday, 23 March 2012

Which type of lubricants are preferred in pharmaceuticals and what is their standards?







Lubricant is a substance introduced to reduce friction and wear between moving surfaces of a machinery.Friction causes heat,so lubricants reduce heat by carrying away the moving surface of the machinery and cool its components.Lubricants also helps to maintain machine parts rust and corrosion free.

Industrial lubricants are prepared from either organic or synthetic compounds.Most of the organic lubricants are prepared from chemical compounds through a number of chemical processing using some additives.Typically lubricants contains 90% base oil (most often petroleum fractions called mineral oils) and less than 10% additives. Vegetable oils or synthetic liquids such as hydrogenated poly olefin's,esters,fluorocarbons and many others are some times used as base oils.The key role of additives used in lubricants is to increase the viscosity of lubricants and reduce oxidation and contamination.Some common additives are antioxidants,anti foaming agents,rust - corrosion inhibitors,metal deactivator's etc.

Lubrication challenges in Pharmaceuticals
Machineries used in pharmaceuticals have many moving parts that require lubricants,to maintain reliable and efficient operation.These range from hydraulics,gear boxes,bearings and chains to vacuum  pumps and compressors.Some major lubricants related issues in pharmaceuticals are discussed below.
  • Lubricants used in the pharmaceuticals must meet basic requirements like wear protection,good lubricity,long life etc.If lubrication is insufficient or lubricant is not suitable for the application high friction  and rapid wear on the compounds may occur.This is quite undesirable in pharmaceuticals because in a clean room the minute wear particle will contaminate the ambient air.(lubricants based on pre fluorinated poly ether oils and PTFE are particularly suited for clean room applications.They offer good wear protection and are chemically resistant to sterilization techniques employed in clean rooms).
  • Lubricant leakage is a major headache in pharmaceuticals because if incidental contact occurs,they do not discriminate against materials with which they come in to contact,so contamination control is a major issue in pharmaceuticals.Hence the usage of lubricants are technically unavoidable pharmaceutical manufacturers are insisted  to use food grade lubricants to reduce the contamination risks,because standard lubricants are mixes of base oils and chemical additives,many of which harm human health if ingested.Food grade lubricants use additive types that are more benign.A good food grade lubricant will use synthetic base oils such as PFO,which offers long oil life.                                                                                                                                                           


Food grade lubricants                                             
Food grade lubricants are suitable for incidental contact with food and pharmaceuticals. They are not intended for human consumption or for contact with skin or mucous membrane.Food grade lubricants composed in such a way that if applicable,technically unavoidable residues in the processed product are innocuous for health,taste and odour, and they do not have any other adverse effect on the product.   
                                                       A food grade lubricant performs in the same way as other lubricant.It provide protection against wear,friction,corrosion and oxidation,dissipates heat and transfer power.It is compatible with rubber and other safety materials as well as provide a safety effect in some cases.

Food grade lubricants categories                                              
The lubricant types of food grade applications are broken in to categories based on the likely hood they will contact with food.The USDA created the original food grade designations H1,H2 and H3,which is the current terminology used.
H1 Lubricants are food - grade lubricants used in food processing environments where there is some possibility of incidental food contact.Lubricant formulations may only be composed of one or more approved base stocks,additives and thickeners listed in 21 CFR 178.3750
H2 Lubricants are lubricants used on equipments and machine parts in locations where there is no possibility that the lubricants or lubricated surface contacts food.Because there is not the risk of contacting food,H2 lubricants do not have the list of acceptable ingredients.they cannot,however,contain intentionally heavy metals such as antimony,arsenic,cadmium,lead,mercury or selenium.Also ingredients must not include substances that are carcinogens,mutagens,teratogens or mineral acids.
H3 Lubricants are also known as soluble or edible oil, are used to clean and prevent rust on hooks, trolly's and similar equipment.


Lubricants for pharmaceutical use must have NSF H1 registration and ISO 21469 certification.


The NSF - H1 registration has established itself as an international standard for lubricants used in the food industry.The H1 registration is based on the US guidelines of sec.21 CFR of the FDA regulations.The USFDA has determined qualitative and quantitative ingredients to be used in lubricants for food industry.The assessment and approval process is carried out by the NSF international.The NSF registered products are listed in White book.The standard H1 describes products,which are to be used where incidental contact with food is possible.


ISO 21469:2006 specifies the hygiene requirements for the formulation,manufacture,use and handling of lubricants which,during manufacture and processing can come in to incidental contact with products used in food,pharmaceuticals,cosmetics,tobacco or animal feeding stuff industries.

When you are using food grade lubricants in pharmaceuticals ensure the following
1.Ensure the availability of MSDS of the lubricant.
2.Ensure the availability of chemical composition of the lubricant (Cross check with 21 CFR 178-3750 lubricants list for incidental food contact). 
3.Pharmaceutical manufacturer must have quality agreements with supplier.
4.Ensure each lot come with certificate of analysis and they must contain approved substances.
5.Lubricants must be tested for sterility once they are sterilized and enter sterile facilities (In case of sterile applications).
6.When food grade lubricants come to contact with products like oral solids their expiration date must be considered.
7.In solid dosage forms lot to lot consistency of the received product must be analyzed for microbial load.





Thursday, 22 March 2012

Why Empty Hard Gelatin Capsules are stored in Temperature & Humidity controlled area

Empty Hard Gelatin Capsules

Why Empty Hard Gelatin Capsules are stored in Temperature & Humidity controlled area?

Capsules are solid dosage forms in which medicinal agents are enclosed in a small shell. Depending on the composition capsules may be hard or soft. Hard gelatin capsules are made from gelatin (Gelatin is a translucent, colorless, brittle (when dry), flavorless solid substance, derived from the collagen- an animal protein).Empty Hard Gelatin Capsules contain 12 - 16% moisture. But the moisture content can vary up on the storage conditions.

Recommended Storage conditions for Hard Gelatin Capsules
Store capsules away from direct sunlight (e.g. windows and skylights)
Store capsules away from hot water/air radiators, hot water pipes and steam pipes.
Store capsules on pallets off the ground.
Store capsules away from potential sources of water condensation e.g. under water pipes.
Do not store empty capsules in freezers.
Hard gelatin capsules shall be stored between 15-25oC (68-75oF) and 45-55% relative humidity to maintain the 12-16% moisture content of capsules.

It is important that this moisture content is maintained and exposure to high temperatures or cycling between high/low temperatures is avoided. When humidity is low capsules become brittle, if stored at high humidity, the capsules become flaccid and the excess moisture content can interact with encapsulated product and can cause stability problems.

If capsules stored at high temperature following defects can occur
Stucking of capsules together in lumps and do not come apart.
Brittle or shatter capsules.
Capsules with distorted shape.
Stucking of capsule cap to body and resists separation. 

What is the difference between Hard Gelatin and Soft Gelatin Capsules?


Both the hard and softgel capsules are made of gelatin.Thus the difference between these two types of capsules lies in the design and manufacturing technology which are detailed below.
Hard Gelatin Capsule
Soft Gelatin Capsule
Made of hard gelatin
Made of soft gelatin
Produced in two halves consisting of a body and cap
Produced as a single piece of gelatin, rather than two halves attached
Mainly used for filling dry and powdered content
Mainly used for oil-based formulations
They’re manufactured using different machines, for shell production and encapsulation.
A different process is employed in manufacturing
Manufacturing and filling is done using the same machine, as part of a single process
Hard gel capsules usually are cylindrical
Can be made in a variety of shapes such as the oval, round, tube-like, fish-like, etc.
These are made of only hard gelatin, colorings, plasticizer and titanium dioxide
Lots of ingredients are used, i.e. soft gelatin, plasticizer, sugars, preservatives, colorings, opacifier, etc.
The ratio of gelatin and plasticizer is 1:0.4
The ratio of gelatin to plasticizer is 1:0.8
Available in a range of sizes
Size variety is limited

Size range of Hard Gelatin Capsules?

The capsule size ranges from 0.16 mils to 28 mils capacity (000,00,0,1,2,3,4,5)

Ingredients of Hard Gelatin Shell Capsules?
Gelatin, Dye, Plasticizer, Sugar, Edible colours, Opacifier, Glycerin, Preservatives

Hard Gelatin Capsules Disintegration Time?
Depending on the size of the capsules disintegration ranges from 3-13 minutes.

Major Steps in Hard Gelatin Capsule Shell Manufacturing
1.Gelatin Preparation 2.Dipping 3.Drying 4.Stripping and Trimming 5.Printing 6.Packing

Common Defects in Hard Gelatin Capsules

Shape
Dent,Bent,Double Cap,Mashed,Short and long caps & Bodies
Colour
Different colour, Discolour
Appearance
Dirt, Hole, Crack, Split, Telescoped, Foreign particle, edge, scrape
Printed Mark
No mark, Improper mark

Key words
Temperature and Humidity requirements for Hard Gelatin Capsules, Difference between Hard and Soft gel capsules, Size range of hard gelatin capsules, Disintegration time of hard gelatin capsules, Major steps in Hard Gelatin Capsules, Major ingredients of hard gelatin capsules, Hard Gelatin capsules major defects




Wednesday, 21 March 2012

what is the difference between Thermoforming and Cold forming technology in Blister packing



What is the difference between Thermoforming and Cold forming Technology in Blister packing?

Thermoforming is a technique that involves heating sheets of PVC prior to insertion into a blister machine. This is typically achieved by passing the sheets between upper and lower heating plates. When a sheet enters a thermoforming blister machine, it is soft and pliable and can be forced to take on the shape of a mold through the application of pressure. In some cases, a mechanical stamp will be used in addition to the application of pressure, particularly when the shape of the mold is difficult or complex.

Cold forming is a technique that does not involve any application of heat. Unlike the thermoforming method that uses clear PVC, this technique uses thin sheets of laminate film that contain 
aluminum. In order to create packaging out of these sheets, a blister machine will typically use a stamp to force it into a form. The aluminum-based film will tend to stretch and retain the shape after the stamp has been removed. This type of blister pack is typically used to contain pharmaceuticals, since the aluminum-based film tends to prevent moisture from entering the packaging.










Benefits of PVDC over PVC as a primary packaging material

PVC(Polyvinyl chloride) and PVDC(polyvinylidine chloride)are used in pharmaceuticals as primary packaging materials,which protect pharmaceutical product against Oxygen and odour permeation,moisture and water vapour transmission and microbial attack.

PVC forming film is called rigid PVC because it is almost free of softening agents and plasticizer. Without plasticizers, PVC blisters offer structural rigidity and physical protection for the pharmaceutical dosage form. The blister cavity must remain accessible by the push-through effect and the formed web may not be too hard to collapse when pressed upon. That is why, PVC sheet thickness is typically chosen between 200µ to 300µ depending on the cavity size and shape.

Rigid PVC is a very clear, stiff material with a low WVTR. It exhibits excellent thermoformability; a high flexural strength; good chemical resistance; low permeability to oils, fats, and flavoring ingredients; easy tintability; and low cost. These properties make rigid PVC the material of choice for blister packaging, and it essentially has 100% of the market for the plastic component. PVC films that are thermoformed have a thickness of about 10 mil. The main disadvantages are the poor barrier against moisture ingress and oxygen ingress; moreover PVC has a negative environmental connotation due to its chlorine content and highly toxic dioxins.

Most PVC sheets for pharmaceutical blisters are 250µ or 0.250 mm in thickness. Typical values for the Water Vapor Transmission Rate (WVTR) of a 250µ PVC film are around 3.0 g/m2/day measured at 38°C/90%RH and the Oxygen Transmission Rate (OTR) is around 20 cc/m2/day. In order to overcome the lack of barrier properties of PVC film, it can be coated with PVDC or laminated to PCTFE or COC to increase the protective properties. Multi-layer blister films based on PVC are often used for pharmaceutical blister packaging, whereby the PVC serves as the thermoformable backbone of the structure. PVC layer can be colored with pigments and/or UV filters.

Polyvinylidene chloride (PVDC)–coated PVC. PVDC plays a critical role in blister packaging as laminations or coatings on PVC. PVDC can reduce the gas and moisture permeability of PVC blister packages by a factor of 5–10. Coated PVC films have a thickness of 8–10 mil; the thickness of the PVDC coat amounts to 1–2 mil. The coating is applied on one side and usually faces the product and the lidding material.

PVDC provide excellent barrier to both oxygen and water vapor while most other barrier polymer offer just one or the other. The gas barrier properties are unaffected by relative humidity, do the performance can be relied on through a wide range of packaging and environmental conditions. All PVDC products on the market are actually copolymers of vinylidene chloride (VDC) and other comonomers. The relative amount of VDC in the copolymer dictates some key properties. With more VDC, the barrier properties are generally better, with less VDC, flexibility usually improves. However, the amount and type of comonomer as well as other additives and processing technology used, will influence other properties such as sealing, surface properties, transparency, glossm coefficient or friction, etc. PVDC coatings have been used with duplex (PVDC/PVC) and triplex (PVDC/PE/PVC) structure being the most common ones used. Approximately, 67% of the barrier blister packaging market uses these PVDC-coated films. Typical coating weights used include 40, 60, 90 and 120g/m2, with the WVTR for a ty pical 120 g/m2 PVDC-coated PVC film being arounf 0.16 g/m2 at 40 oC and 75% RH.






Sunday, 4 March 2012

Why conductivity check is so important in purified water quality testing? (Conductivity and water purity)




 
 
Why conductivity check is so important in purified water quality testing?
 
 
 


Conductivity is the ability of a material to pass an electric current. Since the charge on ions in solution facilitates the conductance of electrical current, the conductivity of the solution is proportional to its ion concentration.

 

Conductivity in water is affected by the presence of inorganic dissolved solids such as chloride, nitrate, sulfate, and phosphate anions (ions that carry a negative charge) or sodium, magnesium, calcium, iron, and aluminum cations (ions that carry a positive charge). Organic compounds like oil, phenol, alcohol, and sugar do not conduct electrical current very well and therefore have a low conductivity when in water. Conductivity is also affected by temperature: the warmer the water, the higher the conductivity. For this reason, conductivity is reported as conductivity at 25 degrees Celsius.

 

The basic unit of measurement of conductivity is the mho or siemens. Conductivity is measured in micromhos per centimeter (µmhos/cm) or microsiemens per centimeter (µs/cm). Distilled water has a conductivity in the range of 0.5 to 3 µmhos/cm.

 

Water purity can be quickly estimated on the basis of electrical conductivity or resistance — very pure water conducts electricity poorly, because the electrical current is transported by the ions in solution, in other words conductivity increases as the concentration of ions increases.

 

Factors which determine the degree of water conductivity includes

1.Concentration or number of ions

2.Mobility of the ion

3.Oxidation state (Valence)

4.Temperature of the water.