The microspheres are one of the novel drug delivery system in which effective therapeutic alternative to conventional or immediate release single-unit dosage forms. Microspheres can be characterized as solid, diameter having between 1–1000μm.there are different types of microsphere explained. These microspheres prepared and fill them in a hard gelatin or compress them directly. The microspheres which are prepared by using different technique that are changes their effectiveness and administration of the dosage form as compare to conventional dosage form. Microsphere will be evaluated by using different methods that analyses quality of the microsphere. The microspheres which will get central place in novel drug delivery in future.

Multiple emulsions are dynamic hetero-dispersed structures in which water concurrently occurs water in oil and oil in water emulsion both controlled by lipophillic and hydrophilic surfactants. The combination of all such surfactants is useful in stabilizing multiple emulsions. Multiple emulsions include water-in-oil-in-water (w / o / w) and oil-in-water-in-oil (o / w / o) type; the former has extensive formulation, preparation techniques, and multiple-emulsion in-vitro analysis methods are checked. With specific reference to multiple emulsions of the w / o / w, different factors influencing the stability of multiple emulsions and stabilize strategies are discussed in detail. It finds wide range of applications in Multiple emulsions in cancer therapy, Multiple emulsions in herbal medicines, Vaccine / adjuvant, Oxygen replacement, Inverse targeting, Multiple diabetes emulsions, Multiple emulsions in food, Drug over doses treatment, etc. In the course of such microencapsulation a few emulsions were also used as an intermediate step in the process of such microencapsulation and are the structures of growing interest in the oral delivery of hydrophilic drugs that become unstable in gastrointestinal tracts such as proteins and peptides. Stability a with developing preparation methods, drug release tests, in vitro release studies, globule size or particle size, stability and rheological characterization of multiple emulsions, will be able to provide a novel carrier mechanism for medicines, cosmetics and pharmaceutical agents.

The main goal of just about every drug delivery system is to supply preferred concentrations of drugs in blood and other body fluids, which would be clinically useful and non-hazardous for a long period of time. The Floating and Mucoadhesive both are coming under the novel drug delivery system in which they considered as predominantly more effective as compared to alternative drug delivery system because this formulation having direct contact with a biological system. The latest developments of FDDS and mucoadhesive including the biological and methodology factors that affect Gastrointestinal residence time, the main mucosal system which is explained, the structure of the main formulation described, approaches to develop single-unit and various different-unit floating and mucoadhesive systems, advantages, and one's categorization and development, in which the material used for floating mucoadhesive formulation preparation and other material which are shown on the rationale of their use in this formulation, aspects characterization are enlisted like Thickness and Diameter Testing, Bioadhesion Test, Drug Content Uniformity Test, X Rays Studies Water Uptake Studies, etc. This review also describes the studies to assess the effectiveness and implementation of floating systems, and applications of mucoadhesive systems.