Cationic nanoemulsions as potential carriers for intracellular delivery.

Successful cytosolic delivery enables opportunities for improved treatment of various genetic disorders, infectious diseases and cancer. Cationic nanoemulsions were designed using alternative excipients and evaluated for particle size, charge, effect of sterilization on its stability, DNA condensation potential and cellular uptake efficiency. Various concentrations of non-ionic and ionic stabilizers were evaluated to design formula for colloidally stable cationic nanoemulsion. The nanoemulsion comprised of 5% Capmul MCM, 0.5% didodecyldimethylammonium bromide (DDAB), 1% phospholipid, 1% Poloxamer 188 and 2.25% glycerol and possessed particle size of 81.6 ± 3.56 nm and 137.1 ± 1.57 nm before and after steam sterilization, respectively. DNA condensation studies were carried out at various nanoemulsion: DNA ratios ranging from 1:1 to 10:1. Cell uptake studies were conducted on human embryonic kidney (HEK) cell lines which are widely reported for transfection studies. The nanoemulsions showed excellent cellular uptake as evaluated by fluorescence microscopy and flow cytometry. Overall, a colloidally stable cationic nanoemulsion with good DNA condensation ability was successfully fabricated for efficient cytosolic delivery and potential for in vivo effectiveness.

Positively charged polymeric nanoparticles: application in improving therapeutic efficacy of meloxicam after oral administration.

The potential of positively charged polymeric nanoparticles in improving therapeutic efficacy of meloxicam (MLX), a poorly water-soluble anti-inflammatory agent was evaluated. MLX loaded positively charged nanoparticles were prepared by using poly-epsilon-caprolactone (PCL) as a biodegradable polymer and didodecyldimethylammonium bromide (DDAB) as a cationic surfactant. The MLX nanoparticles were characterized for particle size and encapsulation efficiency. MLX loaded PCL nanoparticles and MLX suspension were evaluated for their in vivo anti-inflammatory activity and ulcerogenic potential. MLX loaded PCL nanoparticles had particle sizes of approximately 300 nm and the encapsulation efficiency of MLX was approximately 90%. The polymeric nanoparticles significantly improved the anti-inflammatory activity of MLX (P< 0.01) as compared to that of MLX suspension. The higher anti-inflammatory effect was maintained for a longer duration (6 h). The polymeric nanoparticles also resulted in less ulcerogenicity as compared to that of MLX suspension.

Organic solvent-free approach to single step fabrication of Eudragit nanoparticles using Labrasol.

The present investigation describes organic volatile solvent-free approach for the single step fabrication of Eudragit nanoparticles. The solubility of various grades of Eudragit viz. Eudragit L100-55, Eudragit L100, Eudragit S100, Eudragit EPO, Eudragit RSPO and Eudragit RLPO in Labrasol (Caprylocaproyl macrogol-8 glycerides) was determined. We observed that Labrasol has the ability to solubilize various cationic Eudragits such as Eudragit RSPO, Eudragit RLPO and Eudragit EPO at a concentration as high as 200 mg/ml. We also evaluated the ability of Labrasol to act as a nanoparticle stabilizer due to its amphiphilic nature and high HLB of 14. It was observed that Eudragit EPO, Eudragit RSPO and Eudragit RLPO nanoparticles of size 110-150 nm could be easily fabricated using Labrasol as a solubilizer and nanoparticle stabilizer. Transmission electron microscopy was carried out to confirm the size and morphology of the nanoparticles. We could encapsulate hydrophobic drugs such as repaglinide and triclosan in the Eudragit RLPO nanoparticles as Labrasol also had the ability to solubilize these hydrophobic drugs. The ability of Eudragit RSPO and RLPO nanoparticles to condense plasmid DNA was also established. This is the first report that demonstrates the polymer solubilizing potential of Labrasol.

Exploring the potential of N-methyl pyrrolidone as a cosurfactant in the microemulsion systems.

The effect of N-methyl pyrrolidone (NMP) on the phase behavior of two ternary systems, viz. PEG-35-castor oil (CremophoreEL)-glyceryl caprylate/caprate (Capmul MCM)-water and PEG-35-castor oil (CremophoreEL)-isopropyl myristate-water was studied. The study indicated that NMP has considerable influence on the phase behavior of both the systems. NMP increased the area of microemulsion formation in both the systems. Moreover, it also led to reduction/disappearance in the gelling region of the CremophoreEL-isopropyl myristate-water system. These observations allowed us to conclude that NMP can be considered as a cosurfactant for the development of biocompatible microemulsions.

Novel drug delivery systems: potential in improving topical delivery of antiacne agents.

Acne is the most common cutaneous disorder of multifactorial origin with a prevalence of 70-85% in adolescents. The majority of the acne sufferers exhibit mild to moderate acne initially, which progresses to the severe form in certain cases. Topical therapy is employed as first-line treatment in mild acne, whereas for moderate and severe acne, systemic therapy is required in addition to topical therapy. Currently, several topical agents are available that affect at least one of the main pathogenetic factors responsible for the development of acne. Although topical therapy has an important position in acne treatment, side effects associated with various topical antiacne agents and the undesirable physicochemical characteristics of certain important agents like tretinoin and benzoyl peroxide affect their utility and patient compliance. Novel drug delivery strategies can play a pivotal role in improving the topical delivery of antiacne agents by enhancing their dermal localization with a concomitant reduction in their side effects. The current review emphasizes the potential of various novel drug delivery strategies like liposomes, niosomes, aspasomes, microsponges, microemulsions, hydrogels and solid lipid nanoparticles in optimizing and enhancing the topical delivery of antiacne agents.