Topical Drug Delivery to the Posterior Segment of the Eye

Topical drug delivery to the posterior segment of the eye is a very complex challenge. However, topical delivery is highly desired, to achieve an easy-to-use treatment option for retinal diseases. In this review, we focus on the drug characteristics that are relevant to succeed in this challenge. An overview on the ocular barriers that need to be overcome and some relevant animal models to study ocular pharmacokinetics are given. Furthermore, a summary of substances that were able to reach the posterior segment after eye drop application is provided, as well as an outline of investigated delivery systems to improve ocular drug delivery. Some promising results of substances delivered to the retina suggest that topical treatment of retinal diseases might be possible in the future, which warrants further research.

Design and Development of Mupirocin Nanofibers as Medicated Textiles for Treatment of Wound Infection in Secondary Burns

The present study assessed the topical potential of nanofibers loaded with Mupirocin (MUP) for the treatment of burns. Nanofibers of MUP were composed of Polyvinyl Pyrrolidone (PVP), Gelatin Type-A, and Ethanol using two methods: Solvent casting and Electrospinning. Nanofibers were characterized for Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), Drug Content Studies, in-vitro drug permeation, antibacterial and stability studies. The FT-IR studies showed that the Electrospinning technique had a very good mixing of MUP with the polymer. SEM studies showed that the morphology of electrospinning nanofibers had diameters in the range of 70.41 nm- 406.83 nm. The thermal decomposition studies of optimized Nanofiber (E.S.1) were performed by DSC and TGA study and it was found that the formulation had high stability in high-temperature environments. Permeation studies showed that E.S.1 had the highest percentage amount and controlled release of the drug (90 %) up to 8 has compared to other formulations. Nanofibers prepared through the Electrospinning technique showed better antibacterial activity against Staphylococcus aureus as compared to the Solvent casting nanofibers. This research suggested that MUP loaded nanofibers can be potentially used as a topical drug delivery system for the treatment of burns.

A Nanocrystals-Based Topical Drug Delivery System with Improved Dermal Penetration and Enhanced Treatment of Skin Diseases

Topical drug delivery methods are important in the treatment of skin diseases. Drug nanocrystals, which are nanometersized particles of active pharmaceutical ingredients, offer efficient topical delivery with high stability, high drug loading capacity, steady dissolution, and sustained drug release profiles. The use of nanocrystals for the topical delivery of skin disease therapies is currently being evaluated; this review focuses on how nanocrystals facilitate active pharmaceutical ingredient transport across skin barriers, exploring the underlying transportation mechanisms of the nanocrystals and active pharmaceutical ingredient molecules to the dermal and epidermal skin cells. In topical delivery, previous skin treatments, choice of excipients and vehicles, and penetration enhancement strategies critically influence the topical delivery of drug nanocrystals. Various research and applications of drug nanocrystals in skin disease therapy are highlighted in this review, and intellectual property protection for drug nanocrystal formulations, clinical trial data, and products with commercial potential are also discussed.

Emulgel: A Review

Emulgel systems are currently attention to the pharmaceutical sectors because of their substantial potential to act as drug delivery vehicle by incorporating a broad range of drug molecules and higher stability compared to the other dosage form like cream, lotion, gel, etc. Emulsions are either available in an oil in water or water in oil type. These are prepared by the incorporation of the emulsion into the gel with constant stirring at a moderate speed. Incorporation of emulsion into a gel makes it a dual control release system, thereby, increasing its stability. It has better drug release if we compare to other topical drug delivery system. It is non greasy because of the presence of gel phase which enhances patient compliance. Gels has a major limitation for the delivery of hydrophobic drugs, so to overcome this limitation an emulsion based approach is being used so that even a hydrophobic therapeutic drug can enjoy the unique properties of gels. In recent years, these have also been a great interest in the use of novel polymers. These emulgels are having major advantages on vesicular drug delivery systems as well as on conventional systems in various aspects. Various permeation enhancers can enhance the effect; due to this emulgels can be used as better topical drug delivery systems over current drug delivery systems. The emulsion can be use for analgesics and antifungal drugs.

Antifungal Topical Nanoemulgel Containing Miconazole Nitrate

Nanomulgel have emerged as one of the most interesting topical drug delivery system as it has dual release control system i.e. nanoemulsion and gel. Also the stability of nanoemulsion is increased when it is incorporated in gel. Miconazole nitrate is an antifungal medication topically administered to treat skin infections such as athlete’s foot, jock itch and ringworm. The aim of the present research work was to investigate the potential of nanoemulgel in enhancing the topical delivery of hydrophobic drug. MCZ nanoemulsions were prepared using span 80, tween 80, propylene glycol and different conc. of sunflower oil by High pressure homogenization technique. The prepared nanoemulsions were evaluated for pH, drug content, centrifugation, globule size and zeta potential.F2 showed highest drug content 91.26%.The globule size are found to be satisfactory range of nanoemulsion. The drug release kinetics is in the order of F2>F3>F4>F5>F1.And Nanoemulgel is prepared by using Carbopol 934 as gelling agent The release kinetics of nanoemulgel was found to obey zero order kinetics. The nanoemulgel was found to be stable with respect to physical appearance, pH, rheological properties spreadability and drug content at all temperature and conditions for two month. Hence, in the present study it can be concluded that Miconazole Nitrate nanoemulgel formulation is a promising system for the topical drug delivery and also an alternative method to deliver the hydrophobic drugs in water soluble gel bases. Key words: Hydrophobic drugs, Nanoemulgel, Miconazole nitrate, Topical drug delivery.

Nanotechnology for Topical Drug Delivery to the Anterior Segment of the Eye

Topical drug delivery is one of the most challenging aspects of eye therapy. Eye drops are the most prevalent drug form, especially for widely distributed anterior segment eye diseases (cataracts, glaucoma, dry eye syndrome, inflammatory diseases, etc.), because they are convenient and easy to apply by patients. However, conventional drug formulations are usually characterized by short retention time in the tear film, insufficient contact with epithelium, fast elimination, and difficulties in overcoming ocular tissue barriers. Not more than 5% of the total drug dose administered in eye drops reaches the interior ocular tissues. To overcome the ocular drug delivery barriers and improve drug bioavailability, various conventional and novel drug delivery systems have been developed. Among these, nanosize carriers are the most attractive. The review is focused on the different drug carriers, such as synthetic and natural polymers, as well as inorganic carriers, with special attention to nanoparticles and nanomicelles. Studies in vitro and in vivo have demonstrated that new formulations could help to improve the bioavailability of the drugs, provide sustained drug release, enhance and prolong their therapeutic action. Promising results were obtained with drug-loaded nanoparticles included in in situ gel.