Difference between revisions of "Paste (rheology)"

Latest revision as of 10:07, 20 September 2010

For other meanings of paste see Paste (disambiguation)

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In physics, a paste is a substance that behaves as a solid until a sufficiently large load or stress is applied, at which point it flows like a fluid. In rheological terms, a paste is an example of a Bingham plastic fluid.

Pastes typically consist of a suspension of granular material in a background fluid. The individual grains are jammed together like sand on a beach, forming a disordered, glassy or amorphous structure, and giving pastes their solid-like character. It is this "jamming together" that gives pastes some of their most unusual properties; this causes paste to demonstrate properties of fragile matter.

In pharmacology, paste is basic pharmaceutical form. It consists of fatty base (e.g., petroleum jelly) and at least 25% solid substance (e.g., zinc oxide).

Examples include starch pastes, toothpaste, mustard, and putty.

See also

• Gel

v t e Routes of administration / Dosage forms
Oral	Digestive tract (enteral) Solids Pill · Tablet · Capsule · Osmotic controlled release capsule (OROS) · Softgel Liquids Solution · Suspension · Emulsion · Syrup · Elixir · Tincture · Hydrogel Buccal / Sublabial / Sublingual Solids Orally Disintegrating Tablet (ODT) · Film · Lollipop · Lozenges · Chewing gum Liquids Mouthwash · Toothpaste · Ointment · Oral spray Respiratory tract Solids Smoking device · Dry Powder Inhaler (DPI) Liquids pressurized Metered Dose Inhaler (pMDI) · Nebulizer · Vaporizer Gas Oxygen mask · Oxygen concentrator · Anaesthetic machine · Relative analgesia machine	58px 58px 58px 58px 58px 52px
Ocular / Otologic / Nasal	Nasal spray · Ear drops · Eye drops · Ointment · Hydrogel · Nanosphere suspension · Mucoadhesive microdisc (microsphere tablet)
Urogenital	Ointment · Pessary (vaginal suppository) · Vaginal ring · Vaginal douche · Intrauterine device (IUD) · Extra-amniotic infusion · Intravesical infusion
Rectal (enteral)	Ointment · Suppository · Enema (Solution · Hydrogel) · Murphy drip · Nutrient enema
Dermal	Ointment · Liniment · Paste · Film · Hydrogel · Liposomes · Transfersome vesicals · Cream · Lotion · Lip balm · Medicated shampoo · Dermal patch · Transdermal patch · Transdermal spray · Jet injector
Injection / Infusion (into tissue/blood)	Skin Intradermal · Subcutaneous · Transdermal implant Organs Intracavernous · Intravitreal · Transscleral Central nervous system Intracerebral · Intrathecal · Epidural Circulatory / Musculoskeletal Intravenous · Intracardiac · Intramuscular · Intraosseous · Intraperitoneal · Nanocell injection
Additional explanation:	Mucous membranes are used by the human body to absorb the dosage for all routes of administration, except for "Dermal" and "Injection/Infusion". Administration routes can also be grouped as Topical (local effect) or Systemic (defined as Enteral = Digestive tract/Rectal, or Parenteral = All other routes).

da:Masse (materiale) de:Paste (Stoff) lt:Pasta ja:ペースト ru:Паста (лекарственная форма)