Investigations into the formation and characterization of phospholipid microemulsions. IV. Pseudo-ternary phase diagrams of systems containing water-lecithin-alcohol and oil; The influence of oil

Aboofazeli, Reza; Patel, Nilesh; Thomas, M.; Lawrence, M. Jayne

doi:10.1016/0378-5173(95)00125-3

Cited by 85 publications

(49 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In the pseudo-ternary phase diagram, the presence and extent of the microemulsion region depends on the partition coefficient of co-surfactant and the surfactant/ co-surfactant ratio. 38,[40][41][42]46) The butanol used in this study has medium level water solubility; its affinity to the IPM used in Before treatment: baseline (initial assessment). After treatment: at the end of the study (at 6th week, final assessment).…”

Section: Discussionmentioning

confidence: 99%

“…The lecithin/IPM/butanol/water combination is widely used when developing a water-in-oil or oil-in-water type microemulsion. [38][39][40][41][42] The lecithin used in this study consists of 93% phosphatidylcholine, which is slightly too lipophilic to form a balanced microemulsion when used as the sole surfactant. 43) Lecithin tends to form lamellar structures/bilayers, since it has a high critical packing parameter (CPP, approximately 0.8).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Preparation and Evaluation of Topical Microemulsion System Containing Metronidazole for Remission in Rosacea

et al. 2012

View full text Add to dashboard Cite

The aim of this study was to prepare a topical water-in-oil type microemulsion containing metronidazole and to compare its effectiveness with a commercial gel product in the treatment of rosacea. A pseudoternary phase diagram (K m 2 : 1) was constructed using lecithin/butanol/isopropyl myristate/water. The microemulsion was chosen from the microemulsion region in the phase diagram. The formulation was a water-in-oil type microemulsion (droplet size: 11.6 nm, viscosity: 457.3 mPa·s, conductivity: 1.5 µs/cm, turbidity: 6.89 NTU) and the addition of the metronidazole did not alter the properties of the system. The release experiment showed that the release rate of metronidazole from the commercial gel product was higher than that of the microemulsion. Stability experiments showed that the metronidazole microemulsion remained stable for at least 6 months; none of the characteristic properties of the microemulsion had changed, the system retained its clarity and there was no sign that crystallization of metronidazole has occurred. Microemulsion was compared to a gel product in a randomized, double-blind, baseline-controlled, split-face clinical trial for the treatment of patients. After the 6-week treatment period there was a statistically significant difference in reduction of the main symptoms of rosacea. Of the patients treated with the microemulsion, 17% experienced complete relief from inflammatory lesions, and 50% from erythema. The microemulsion resulted in complete relief in 38% of the patients with telangiectasia while the commercial product did not provide any relief of telangiectasia symptoms. In conclusion, the microemulsion containing metronidazole was found to be more effective in reducing the symptoms of rosacea compared to the commercial gel product. Key words microemulsion; metronidazole; rosaceaRosacea is a chronic skin disorder of unknown etiology that is more common in women than men.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Preparation and Evaluation of Topical Microemulsion System Containing Metronidazole for Remission in Rosacea

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Because of its high lipophilicity and strong tendency to form liquid crystalline structures, lecithin will not generally form microemulsions with pharmaceutically acceptable oils, such as isopropyl myristate and ethyl oleate, without the aid of a cosurfactant (2)(3)(4). We have previously reported on the ability of the commercially available egg lecithin Ovothin 200 (0200) to produce an optically clear, one-phase "microemulsion" in combination with isopropyl myristate and water in the presence of a series of short-chain alcohol cosurfactants at different surfactant/cosurfactant weight ratios, K m , (5) by means of phase-behavior studies.…”

Section: Introductionmentioning

confidence: 99%

Particle size analysis of concentrated phospholipid microemulsions: I. Total intensity light scattering

2000

View full text Add to dashboard Cite

Water-in-oil phospholipid microemulsions prepared from a constant total surfactant/cosurfactant concentration of 25 wt% at four different lecithin/alcohol weight ratios (K m of 1:1, 1.5:1, 1.77: 1, and 1.94:1) and containing water concentrations (or volume fractions) ranging from 2.0 to 26 wt% (or 0.04 to 0.26) have been examined at 298 K using total intensity light scattering. The data obtained were analysed using the hard-sphere model of Percus-Yevick, modified to account for the partitioning of the alcohol between the various phases. The light-scattering results showed that, regardless of the K m or the alcohol used, a minimum water concentration of at least 9 wt% was required for the formation of a microemulsion; although this value was reasonably constant for each of the alcohols investigated, there was a tendency for a slightly higher concentration of water to be required for microemulsion formation at higher K m values. Simple calculations suggested that a microemulsion was formed only when sufficient water was present to satisfy the hydration of both the phospholipid head groups and the hydroxyl groups of the cosurfactant associated with the droplet. At water concentrations lower than this minimum value, a cosolvent system was observed. In all systems above this minimum concentration, as the concentration of water increased, the size of the microemulsion droplets also increased. Surprisingly, however, there was little difference in the size of the microemulsion droplets obtained with the different alcohols, regardless of the K m , although for a particular alcohol there was some indication that the higher K m systems produced the slightly smaller droplets for an equivalent water

show abstract

“…The main problem in a microemulsion application is a high concentration and a narrow range of physiologically acceptable surfactants and co-surfactants [23,24]. Large surfactant concentration (10-40%) determines their stability [25].…”

Section: Challenges In Nose To Brain Drug Delivery Via Microemulsionmentioning

confidence: 99%

A Recent Review on Nasal Microemulsion for Treatment of CNS Disorder

Jaiswal

Darekar

Saudagar³

2017

Int J Curr Pharm Sci

View full text Add to dashboard Cite

Nasal route is found to be valuable for targeting drugs to CNS via a different mechanism. The advantages, disadvantages, various aspects of nasal anatomy and physiology, mechanism of drug transport from nose brain, drug selection criteria to cross BBB/Blood-CSF barrier are discussed briefly. Nowadays many drugs have better systemic bioavailability through nasal route as compared to oral administration. In addition, intranasal drug delivery enables dose reduction, rapid attainment of therapeutic blood levels, quicker onset of pharmacological activity, and fewer side effects. There are various approaches in delivering a therapeutic substance to the target site. One such approach is using microemulsion as a carrier for the drug. The main purpose of this study is the use of microemulsion technology in drug targeting to the brain along with mechanism of the nose to brain transport, formulation and formation of the microemulsion and its characterization.

show abstract

Investigations into the formation and characterization of phospholipid microemulsions. IV. Pseudo-ternary phase diagrams of systems containing water-lecithin-alcohol and oil; The influence of oil

Cited by 85 publications

References 13 publications

Preparation and Evaluation of Topical Microemulsion System Containing Metronidazole for Remission in Rosacea

Preparation and Evaluation of Topical Microemulsion System Containing Metronidazole for Remission in Rosacea

Particle size analysis of concentrated phospholipid microemulsions: I. Total intensity light scattering

A Recent Review on Nasal Microemulsion for Treatment of CNS Disorder

Contact Info

Product

Resources

About