Mineral based adjuvants: A number of minerals are used as an adjuvants. Examples include Calcium phosphate, Calcium chloride. But aluminium based compounds are mostly used- Aluminium phosphate and aluminium hydroxide. The method of production is mixing the antigenic solution with aluminium phosphate or other salt which is formerly precipitated under chemically defined conditions. These are generally termed as aluminium adsorbed vaccines. The mode of action is "depot formation" at the site releasing the antigen slowly thereby producing sustained exposure. The aluminium salts cause inflammation at the site of injection and this is sometimes useful in attracting the immunocompetant cells to the site. Major drawbacks include: * elicitation of humoral response only * Not capable of lyophilization * Sometimes destruction of their structure Oil based adjuvants: The use of oils as adjuvants was proposed in early 20th century. However the first of its kind the Freund's complete adjuvant (FCA) came into lime light in 1937. It is a mixture of paraffin oil and dead mycobacteria and Arlacel A is generally used as an emulsifier. Another example is the Freund's incomplete adjuvant (FIA). It differs from the former adjuvant in lacking the mycobacterial component and hence possess a lesser adjuvanticity. FCA also has an immunostimulatory properties. Though it has many vantages it is too toxic for human use. Other examples include Squalene in water based emulsions, Polyalcohols like Tweens and Spans. THIS BLOG IS FREE OF PLAGIARISM. Ref: Pharmaceutical Biotechnology Concepts and Applications by Gary Walsh, Wiley Publications, 2007 edition, Page no: 413-414. THE FORTNIGHT TIP: Who is the most influential person in your life..? I asked this question to my educatees. One of them gave an immediate answer sir, The facebook owner. Is this your answer too? I could hear your invoices saying Yes!! The person who influences you may not be such an illustrious man or woman. He can also be a common labour or any other common man. Your friend who shares with you the most may also influence you. I say this influence should be an incontrovertible and positive. In such hormonal relation you can achieve great heights. Good Luck!!