Salunkhe Kishor S

The expense and complications in new drug entities have increased since last 3 decades, with concomitant recognition of the therapeutic advantages of controlled drug deliver. So focus has been given on development of sustained or controlled release drug delivery system. Bilayer tablet is new era for the successful development of controlled release formulation along with various features to provide a way of successful drug delivery system. Bilayer tablet is better than the traditionally used mouthwash, sprays, and gels. For promoting patient convenience and compliance pharmaceutical industries interested in developing a combination of two or more API’s in a single dosage form. Bilayer tablet is improves beneficial technology to overcome the shortcoming of the single layered tablet. Bilayer tablet can be a primary option to avoid chemical incompatibilities between APIS by physical separation, and to enable the development of different drug release profile using different technologies. So use of bilayer tablet is a very different aspect for anti-inflammatory and analgesic. Several pharmaceutical companies are currently developing bilayer tablet for a variety of reason: patent extension, therapeutic, marketing to name a few. To reduce capital investment quite often existing but modified tablet presses are used to develop such tablets. The present article provides an introduction of bilayer tablet technology, advantages, disadvantages, different approaches, types of bilayer tablet, various techniques, quality and GMP requirements of bilayer tablets.

Lyophilization is promising approach to increase the shelf life of liposome. The major limitation in the widespread use of liposome is its instability. The aim of this study was to investigate the effect of lyophilization either in the presence or in the absence of lyoprotectant on liposome properties Lyophilization is used to ensure an increased shelf life of liposomes by preserving them in dry state more stable than the aqueous dispersion. When stored as aqueous system the encapsulated drugs are released & the liposome might aggregate or fuse. The process of lyophilization without cryoprotectant resulted in particle size increased & significant content leakage. This review work suggests that the investigation of stability of lyophilized liposomes containing PC (Phosphatidyl Choline) & cholesterol. Liposomes sphere-shaped vesicles consisting of one or more phospholipids bilayer in which both hydrophilic & hydrophobic drug entity can be incorporated. Due to their size & hydrophobic & hydrophilic character liposomes are promising for drug delivery. This structure turns liposomes into ideal drug carriers, since hydrophilic drugs tend to entrapped in the core; while hydrophobic ones will be entrapped within the lipid bilayers. Liposome is one of the most successful drug delivery system applying nanotechnology to potentiate the therapeutic efficacy & reduce toxicities of conventional medicines. The encapsulation efficiency partially depends upon the logP of drug. Lyophilization is a strategy often employed to improve liposomal formulation stability, due to reactivity being far less pronounced in the solid versus aqueous state.

Liposome are the concentric bilayer means core of center in which aqueous volume entirely envelope by the phospholipids bilayer used to transfer enzymes, protein and drugs to targets cancer cell or tissue. These are chemical moieties in which action towards target organ. It was first discovered by 1965 and soon was proposed drug delivery system. There are numerous application like anti fungal, anti cancer, anti inflammatory and anesthetic drugs. The magic bullet concept of Paul Ehrlich through very late, offers a logical solution to the age old problem unrelated and unwanted effect of therapeutic agent and optimizing the drug therapy in its true sense. Drugs would be targeted by virtue of groups having affinity for specific cells, tissues or organs. Liposome having also its modifications or upgraded versions likes enzymosomes, hemosomes, virosomes, and erythrosomes. Liposome has emerged as a dynamic mode for targeted drug delivery. Ligands confer specificity on a non specific reagent. Although controlled and sustained drug delivery can be considered as the magic bullet concept. We can look forward to many more clinical products in the future.