| Full Text | Transfersome is a term registered as a trademark by the German company IDEA AG. The name means “carrying body”, and is derived from the Latin word 'transferre', meaning ‘to carry across’, and the Greek word ‘soma’, for a ‘body’. A Transfersome carrier is an artificial vesicle designed to be like a cell vesicle or a cell engaged in exocytosis, and thus suitable for controlled and, potentially targeted, drug delivery.a Transfersome is a highly adaptable and stress-responsive, complex aggregate. Its preferred form is an ultradeformable vesicle possessing an aqueous core surrounded by the complex lipid bilayer. Interdependency of local composition and shape of the bilayer makes the vesicle both self-regulating and self-optimising. This enables the Transfersome to cross various transport barriers efficiently, and then act as a Drug carrier for non-invasive targeted drug delivery and sustained release of therapeutic agents.
Liposomes and Niosomes are the vesicular carrier systems which have received a lot of attention over the last decade as a means of transdermal drug delivery, in most cases transdermal drug penetration has not been achieved. To overcome these problems a new type of carrier system called “transferosomes” was introduced for the effective transdermal delivery of number of low and high molecular weight drugs. The concept of transferosomes was developed, as recent tool for effective transdermal drug delivery, by Ceve and coworkers in 1992.
These are modified forms of the liposomes. It consist of both hydrophilic and hydrophobic properties, greater deformability than the standard liposomes and well suitable for skin permeation. A transferosomes, in functional terms, may be described as lipid droplets of such deformability that permits its easy penetration through the pores much smaller than the droplets size. They protect the encapsulated drug from metabolic degradation. From the composition point of view, a transferosomes is a self adaptable and optimized mixed lipid aggregate. They act as depot,releasing their content slowly and gradually.
Transferosomes have been developed in order to take advantage of phospholipids vesicles as transdermal drug carrier. These self optimized aggregates, with ultra-flexible membrane, are able to deliver the drug reproducibly either into or through the skin, depending on the choice of administration or application, with high efficiency. These vesicular transferosomes are several orders of magnitude more elastic than the standard liposome’s and thus well suited for the skin penetration. Transferosomes overcome the skin penetration difficulty by squeezing themselves along the intracellular sealing lipids of stratum corneum. Flexibility of transferosomes membrane is achieved by mixing suitable surface active agents in the proper ratios. The resulting flexibility of transferosome membrane minimize the risk of complete vesicle rupture in the skin and allow transferosomes to follow the natural water gradient across the epidermis ,when applied under non occlusive condition. Transferosomes can penetrate the intact stratum corneum spontaneously either through intracellular route or Tran cellular route.
METHOD OF PREPARATION OF TRANSFEROSOMES:
Materials required for preparation of the trasnsferosomes are phospholipids like Soya phosphatidyl choline, egg phosphatidyl choline, etc. surfactants like sodium cholate, tween-80, span-80 etc, alcohol like methanol, ethanol etc, dye (Rhodamine-123, Nile-red) for confocal scanning laser microscopy (CSLM) and saline phosphate buffer.
Phospholipids ---- Soya phosphatidyl choline,egg phosphatidyl choline,dipalmitoyl phosphatidyl choline -->Vesicles forming component
Surfactant --- Sod.cholate,Sod.deoxycholate,Tween-80,Span-80 -->For providing flexibility
Alcohol --- Ethanol, methanol -->As a solvent
Buffering agent --- Saline phosphate buffer (pH 6.4) -->As a hydrating medium
Dye --- Rhodamine 123, Nile-red -->For Confocal scanning laser microscopy (CSLM)
The mixture of vesicle forming ingredients, that is phospholipids and surfactant were dissolved in volatile organic solvent, organic solvent evaporated above the lipid transition temperature using rotary evaporator. Final traces of solvent were removed under vacuum for overnight. The deposited lipid films were hydrated with buffer by rotation at 60 RPM/min. for 1hr at the corresponding temperature. The resulting vehicles for 2hrs at room temperature. To prepare small vesicles, resulting LMVs were sonicated at room temperature or 500C for 30min. the sonicated vesicles were homogenized by manual extrusion 10 times through a sandwich of 200 and 100nm polycarbonate membrane. Then finally we got the Transferosome.
Usage:
Transfersome technology is best suited for non-invasive delivery of therapeutic molecules across open biological barriers. The Transfersome vesicles can transport across the skin, for example, molecules that are too big to diffuse through the barrier. Examples include systemic delivery of therapeutically meaningful amounts of macromolecules, such as insulin or interferon, across intact mammalian skin. Other applications include the transport of small molecule drugs which have certain physicochemical properties which would otherwise prevent them from diffusing across the barrier.
Peripheral tissue targeting--
Another attraction of the Transfersome technology is the carriers ability to target peripheral, subcutaneous tissue. This ability relies on minimisation of the carrier-associated drug clearance through cutaneous blood vessels plexus: the non-fenestrated blood capillary walls in the skin together with the tight junctions between endothelial cells preclude vesicles getting directly into blood, thus maximising local drug retention and propensity to reach the peripheral tissue targets.
ADVANTAGES:
These has greater advantages-
--These shows greater permeation of the drugs through the skin because of its flexible membranes.
--These serves as carrier for both small and large molecular weight drugs.
--In transferosomes percentage of the drug entrapment is more.
--Protect the entrapped drug from atmospheric degradation.
--These are biocompatible and biodegradable as they are prepared with natural phospholipids.
--By selecting the suitable composition and administration mode we can site specific therapy.
LIMITATIONS:
Like liposomes, transfersomes have certain limitations-
- Transfersomes are chemically unstable because of their predisposition to oxidative degradation,
- Lack of purity of the natural phospholipids comes in the way of adoption of transfersomes as drug delivery vehicles and
- Transfersomes formulations are expensive to prepare.
APPLICATIONS:
Transferosomes has wide applications in transdermal delivery of drugs as carriers when applied nonocclusively.
1.As carries for NSAIDs like Diclofenac, etc.
2.As carrier for proteins.
3.As a carrier for insulin.
4.As a carrier for interferon.
5.As a means of transdermal immunization.
6.As a carrier for corticosteroids.
7.As a carrier for topical analgesics and anesthetic agents.
8.As a carrier for anticancer drugs.
9.have also been used to improve the therapeutic efficiency of cyclosporine, and the site specificity and safety of corticosteroids
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