am asynchronous

• Primary pack

  In direct contact with the medicine so there must be no compatibility issues
• Primary pack materials

  • Aluminium
  • Glass
  • Aluminium + rubber
  • Plastic (various types)
  • Plastics + aluminium foil
• Primary pack types

  • Multiple-unit pack
  • Single-unit pack
• Secondary packs

  Contain the primary pack and various ancillary components
• Secondary pack components

  • Patient information leaflet (PIL)
  • Delivery aid, e.g. spoon, spatula (paste/ointment), applicator (pessary)
• Secondary pack material

  Thick paper known as paperboard.

  Plastics are sometimes used, particularly with fragile primary packs, e.g. glass vials/ampoules
• Principal purpose of secondary packs

  Protection against mechanical damage to a medicine, but also protects against other factors, e.g. light
• Glass

  • Possesses excellent barrier properties against all substances
  • Different types of glass are available, and they vary in their degree of inertness
  • Fragile and heavy but can be moulded into different shapes
  • It is widely recycled.
  • Consisting of a silica (silicon dioxide; SiO2) in a 3D network, glass is generally not referred to as being polymeric
• Neutral glass (Type I)

  A borosilicate glass containing significant amounts of boric oxide, aluminium oxide alkali and/or alkaline earth oxides
• Soda-lime-silica glass (Type II or III)

  A silica glass containing alkali metal oxides, mainly sodium oxide and alkaline earth oxides, mainly calcium oxide
• All types of glass are resistant to heat and can be autoclaved (121 °C)
• Alkali components may leach from glass causing chemical instability
• Plastics


  • Polymers used extensively in packaging
  • They can be strong/breakable, rigid/flexible, clear/opaque, thermoplastic/thermosetting
  • Whether amorphous or crystalline can impact properties
• Amorphous polymers, e.g. polyvinyl chloride (PVC)


  • Can have good transparency (plastic tablet bottle)
  • Often "plasticized" to make it more flexible (iv infusion bags)
  • Some permeability to water and organic vapour
• Crystalline / semi-crystalline polymers, e.g. polyvinylidene chloride (PVDC)


  • Tough and stiff / good heat resistance
  • Chemically inert
• PVC / PVDC films

  • PVC (amorphous) tough, low cost and easily coloured, but a poor barrier
  • PVDC (crystalline) provides protection against water vapour but is expensive and can be brittle
  • Commonly used in blister pack manufacture + aluminium foil
• Plastics (polymers)

  • Polyvinyl chloride (PVC)
  • Polypropylene (PP)
  • High-density polyethylene (HDPE)
  • Polyethylene terephthalate (PET)
• Polyvinyl chloride (PVC)


  Very widely used but there are environmental concerns around plasticizer use
• Polypropylene (PP)

  • Good heat resistance: can be autoclaved at 121 °C
  • Can be used when rigidity required
• High-density polyethylene (HDPE)


  • Not impermeable to vapours
  • Good heat resistance: can be autoclaved at 121 °C
• Polyethylene terephthalate (PET)


  • Less permeable to oxygen than HDPE
  • Parabens absorption has caused concerns
• Metal


  • Mechanical strong / shatterproof (but can be flexible/malleable)
  • Able to withstand heat
  • Impermeable to light, liquids and vapours
• Metals can be expensive, heavy and interact with the medicine (coating with plastics can prevent this)
• Aluminium

  • Impermeable to moisture, oxygen/ other gases, microbes
  • Used in inhalers, collapsible tubes
  • Foils used in blister packs
• Tinplate

  • Steel coated with tin
  • Often used in closure manufacture
• Paper and paperboard (paper >250 g/m2 or > 300 μm thickness)


  • Primarily used in secondary pack manufacture
  • Primary pack: Paper was traditionally used for wrapping powders and is still used in sachet manufacture and packaging of effervescent tablets
• Cellulose


  A polysaccharide, the main component of paper and paperboard
• Guidance on packaging for pharmaceutical products published by WHO in 2002

  Packaging should be reduced and recyclable
• Sustainable pharmaceutical packaging market currently at $71.6 billion and estimated to double by 2027
• Examples of approaches and technology

  • Paperboard from sustainably-managed forests or recycled material
  • Plastics from post-consumer recycled (PCR) materials
  • Polyethylene (PE) from sugarcane makes up 50% of blister packaging in one new product
  • Aluminium oxide incorporated into PE can impart barrier properties equivalent to aluminium foil laminates – also is recyclable
• Sugarcane (Saccharum spp.)

  Used to produce sustainable polyethylene for packaging
• Types of glass


  -neutral glass type l

  -sodalimesilica glass type ll or lll
• Rheology


  Study of the flow and deformation of matter (fluids)
• Viscosity


  The resistance to flow, i.e. if viscosity is high then flow is reduced
• Viscosity: the basics

  1. the top Moves fastest

  2. the bottom is almost Stationary

  3. Rate of flow (shear rate) is directly proportional to the applied stress (shear stress)

  4. Viscosity = shear stress / shear rate

  5. Fluids which obey this relationship are referred to as Newtonian fluids

  6. Relative motion between adjacent layers of a moving fluid is referred to as "shear"
• Fluid

  • Chloroform
  • Water
  • Ethanol
  • Glycerol
  • viscosity inc going down
• Viscosity is inversely related to temperature
• Newtonian fluids


  Fluids which obey the relationship: shear rate = shear stress / viscosity
• The slope of the "rheogram" (plot of shear rate vs shear stress) will be the viscosity
• Non-Newtonian fluids

  Fluids which deviate from the Newtonian relationship between shear rate and shear stress