drug delivery.

Solid lipid nanoparticles (SLNs) are the superseding drug delivery system in the nanotechnology sphere. SLNs has been developed at the beginning of 1990s with potential applications in the field of pharmaceuticals, cosmeceuticals, clinical medicine along with research as a substitute to the traditional colloidal carrier systems such as emulsions, liposomes since they exclude those downsides of the traditional system. SLN s offers a great way for controlled drug delivery and site targeting drug delivery as well. This article gives general information about the solid lipid nanoparticles, their production procedures and characterization. In addition to that, the recent advancements of drug delivery systems using SLNs were reviewed.

The essay is a short overview of the chemistry, pharmacology, pharmacokinetics, clinical uses and the delivery aspects of calcitonin. It will deal with different routes of delivery of calcitonin with the focus lying primarily on the intra-nasal delivery and oral delivery of the hormone.  Calcitonin was initially administered as a subcutaneous/ intra-muscular injection and to overcome certain problems associated with these delivery routes such as patient compliance, inflammation at the site of injection, hypersensitivity reactions and stability of the formulation other routes of delivery are being explored and the most successful route of administration so far is the intra-nasal route. The essay will also give brief information of the nasal spray available in the market currently and the pump-system used for the intra-nasal delivery. The oral route of administration is also being dealt with in some detail as it is one of the most promising routes for delivery of calcitonin and other such peptide molecules and has a bright future. In vitro and in vivo research towards making a successful oral delivery formulation is being carried out and this essay gives a brief overview of some important areas studied so far.

Bioadhesion can be defined as the process by which a natural or a synthetic polymer can adhere to a biological substrate. When the biological substrate is a mucosal layer then the phenomena is known as mucoadhesion. The substrate possessing bioadhesive property can help in devising a delivery system capable of delivering a bioactive agent for a prolonged period of time at a specific delivery site. The current review  provides  a good insight on mucoadhesive polymers, the phenomenon of mucoadhesion and the factors which have the ability to affect the mucoadhesive properties of a polymer. This review also considers the basic mechanisms by which mucoadhesive can adhere to a mucous membrane  in terms of the nature of the adhering surfaces and the forces that may be generated to secure them together. Mucosal adhesion is backed by several theories which include electronic, adsorption, wetting, diffusion, fracture and mechanical. Stages of mucoadhesion include contact stage and consolidation stage.