*3.1.2 Oral and topical drug delivery systems*

Owing to patient compliance, convenience, ease of formulation and higher absorption in the intestine, oral drug delivery is the most widely distributed and preferred form of drug administration.

When compared to conventional oral formulations, nano emulsion formulations provide several benefits in oral drug administration. Some of these benefits include increased absorption, improved clinical potency and decreased drug toxicity [33]. Hence, drugs such as steroids, hormones, diuretics and antibiotics can be ideally delivered using nano emulsions.

Topical drug delivery also has several advantages over other modes of drug administration such as the avoidance of hepatic first pass metabolism, reduction of toxicity and targeted drug delivery to the affected portion of the skin. Here selfadministration is also possible. The transparent nature and fluidity of nanoemulsions not only gives a pleasant skin feel but also helps in eliminating the drug input by just removing the transdermal patch without any irritation [32].

Owing to the large surface area of the droplets, nanoemulsions enable rapid penetration of active ingredients through the skin. This is one of the most valuable properties of nanoemulsions due to which the use of special penetration enhancers which cause incompatibility of the formulation can be minimized [33].

## *3.1.3 Ocular and pulmonary drug delivery*

For the treatment of eye diseases, drugs are delivered topically in ocular dosage forms such as solutions, suspensions and ointments. Due to physiologically

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*An Update on Nanoemulsions Using Nanosized Liquid in Liquid Colloidal Systems*

absorption and also to attain prolong release profile [33].

resulting in stimulation of antigen-specific T-cells [35].

submicron emulsions for pulmonary delivery [32].

equilibrium also shifts towards condensation [36].

**3.3 Nanoemulsions as non-toxic disinfectant cleaners**

Parachlorometaxylenol (PCMX) marketed as EcoTru [36].

*3.4.1 Encapsulation of lipophilic components using nano-emulsions*

• Mask the unpleasant taste or odor of some bioactive materials.

(coating, matrix, membrane, capsule, or shell) [38]. This technology is used in food industry to:

• Increase the bioavailability of some components.

**3.4 Nanoemulsions in the food sector**

**3.2 Nanoemulsions in biotechnology**

reactions [33].

protective mechanisms such as tear dilution, lacrimal drainage, protein binding and enzymatic degradation which are activated as soon as the ophthalmic solutions of the drug are applied, typically less than 3% of these topically applied drugs permeate the corneal epithelium, reach the aqueous humor and finally enter the systemic circulation. O/W Nanoemulsions (Oil in Water nano emulsions) have been researched for ocular administration to dissolve poorly soluble drugs, to increase

Cationic submicron emulsions are promising carriers for DNA vaccines to the lung since they are able to transfect pulmonary epithelial cells thereby inducing cross priming of antigen-presenting cells and directly activate dendritic cells,

There might be adverse side effects of oils and surfactants on the alveoli of lungs. Hence extensive studies are required for the development of successful inhalable

Nanoemulsions serve as a waterproof medium for bio-catalytic or enzymatic reactions to occur. The enzymes in low water content exhibit greater solubility in non-polar reactants and higher thermal stability. As a result, the thermodynamic

Reactions such as synthesis of esters, peptides and sugar acetals transesterification, hydrolysis and steroid transformation are catalyzed by enzymes in nano-

emulsions. Lipases are the most widely used class of enzymes in microemulsion-based

The non-toxic disinfectant cleaner developed by Enviro Systems Inc. has wide applications in commercial markets such as healthcare, hospitality, travel, food processing, and military. This product which kills a wide spectrum of bacteria, virus and fungi in 5–10 minutes without any hazards needs no warning labels. This can be absorbed through the skin, inhaled or swallowed without causing any irritation to the eyes and does not cause any harmful effects [33]. One such NE is

Lipophilic compounds such as flavors, omega3fatty acids, vitamins, nutraceuticals and preservatives can be encapsulated, stabilized and delivered using nanoemulsions. This is one of the emerging fields in the food industry [37]. Research is mainly focused on nanoemulsion technology that is suited for functional foods.

Encapsulation is a useful technique to deliver bioactive molecules within living cells. Here, the bioactive ingredient is entrapped in a core or filled within a carrier

*DOI: http://dx.doi.org/10.5772/intechopen.84442*
