Emulsion Rheology
Laba Dennis in Rheological Proper ties of Cosmetics and Toiletries, 2017
The selection of the correct emulsifier is therefore one of importance. This process becomes more complex because two or more co-emulsifiers give more flexibility and control than one emulsifier. For example, Talman and Rowan (1970a) investigated a range of fatty alcohols and fatty acids of different chain lengths and chemical configurations to evaluate their ability to increase the viscosity and yield value of an O/W emulsion. Generally, the viscosity of the finished material increased as the carbon chain length increased. Barry (1970) was able to alter the consistency of O/W emulsions from fluid to semisolid by the particular mixture of the surfactant/fatty alcohol type. He found that the use of cetostearyl alcohol produced a higher-viscosity emulsion and better stability than either cetyl or stearyl alcohol or ratios of them. This was due to the formation of a viscoelastic gel structure, a “self-bodying action” that increased the viscosity and stabilized the emulsion. This characteristic was discussed earlier in Section II.A. Fukushima et al. (1977) and Fukushima and Yamaguchi (1983) investigated the mechanism for the network’s formation and concluded that cetostearyl alcohol crystallizes in an a-(hexagonal) form to make lamellar lyotropic liquid crystals with the coexisting emulsifier and water. Henkel Corp. (1991) can provide a wide variety of these materials.
Topical Formulations for Onychomycosis: A Review
Andreia Ascenso, Sandra Simões, Helena Ribeiro in Carrier-Mediated Dermal Delivery, 2017
Monti et al. [119] purposed to evaluate the water-soluble film-forming agent hydroxypropyl chitosan (HPCH) included in an experimental nail lacquer (P-3051) containing ciclopirox. HPCH is a water-soluble derivative of chitosan. Chitosans are polysaccharides derived from chitin and natural components of the exoskeleton of crustaceans being widely employed in medicine for their wound healing, bacteriostatic, skin moisturizing, and protecting properties. In particular, HPCH was chosen considering its favorable properties, such as high water solubility; high plasticity; affinity to keratin; wound-healing activity; high compatibility with human tissues, etc. P-3051 was composed of 1% HPCH, 1% cetostearyl alcohol, 73% ethyl alcohol (95°), 4% ethyl acetate and 13% purified water. This formulation was compared with a commercial brand (Penlac™) constituted by 8% ciclopirox, ethyl acetate, isopropyl alcohol, butyl monoester of poly(methylvinyl ether/maleic acid) in isopropyl alcohol. Bovine hoof membranes were used as the human nail plate model. Drug concentrations were determined by HPLC (high performance liquid chromatography). Regarding lag times, the respective values obtained were 3.36 ± 0.46 h for P-3051 vs. 12.48 ± 1.31 for Penlac™. The percentage of permeated drug (Q%30h) was also significantly different for the two formulations: 2.58% for P-3051 vs. 1.06% for Penlac™. In fact, a faster drug penetration time might allow the drug to permeate the nail before the hydro soluble film is degraded. Greater efficiency of P-3051 could be attributed to a particular affinity of HPCH to the nail matrix, resulting in an intimate contact and strong adhesion of the lacquer to keratin substrate [119].
Nanocarrier Technologies for Enhancing the Solubility and Dissolution Rate of Api
Debarshi Kar Mahapatra, Sanjay Kumar Bharti in Medicinal Chemistry with Pharmaceutical Product Development, 2019
These are the excipients with HLB value greater than 12 and these possess ability to self-emulsify and thus used in self-emulsifying drug delivery systems. These synthesized as a mixture of polyethylene glycols (PEG) with hydrolyzed vegetable oils. Also, the reactions of ethylene oxide with alcohol and sorbitan esters give cetostearyl alcohol ethoxylates (cetomacragol) and ether ethoxylates. Cremophor, is another class of compound widely used as a water-soluble surfactant. It includes ethoxylated hydrogenated castor oil (Cremophor RH 40 and RH 60) and non-hydrogenated castor oil, e.g., ethoxylated castor oil (Cremophor EL).
Development of lipid nanoparticles for transdermal loteprednol etabonate delivery
Published in Journal of Microencapsulation, 2022
Burcu Üner, Samet Özdemir, Çetin Taş, Yıldız Özsoy, Melike Üner
Loteprednol etabonate (LE) was gratefully donated by Deva İlaç Sanayi ve Tic. A.Ş. (Turkey). Compritol® 888 ATO, Compritol® E ATO, and 1-tetradecanol were kindly provided by Gattefossé (France). Cutina® CP, Geleol™, Gelucire® 50/13, Imwitor® 491, Imwitor® 900 K, Isopropyl myristate, and cetostearyl alcohol were purchased from Ataman Kimya A.Ş. (Turkey). Oleic acid and castor oil were purchased from BASF (Germany). Olive oil purchased from Arpaş Arifoğlu Pazarlama Dağıtım ve Ticaret A.Ş. (Turkey). Cremephor® EL, cetostearyl alcohol (CA), Nacol 16–98, and Cremephor® RH40 were provided from Sigma-Aldrich (Germany). Lutrol® F68, Tween® 80, and Labrasol® were purchased from BASF (USA). All other chemicals were of analytical grade.
Therapeutic challenges in ocular delivery of lipid based emulsion
Published in Egyptian Journal of Basic and Applied Sciences, 2018
Rahul Tiwari, Vikas Pandey, Saket Asati, Vandana Soni, Dharmendra Jain
The employment of surfactants depend on the type of emulsion i.e. (O/W) or (W/O) along with the nature of the drug partitioning in the oil or aqueous phase. Both water insoluble and water soluble surfactants are used having proper hydrophilic-lipophilic balance (HLB) are used as per the requirement [50]. The water insoluble surfactants can form micelles but due their inadequately hydrophilic nature, they are not able to self-emulsify. The water soluble surfactants, such as cetostearyl alcohol ethoxylate ‘cetomacrogol’, are the most frequently used surfactants in case of self-emulsifying drug delivery systems. These components which have the HLB value of near to 12 are able to form micelles at low concentrations by dissolving in pure water [51]. The concept of non-irritant and non-toxic property is needed to be considered depending on the HLB value. Non-ionic surfactants are versatile functioning agent for fabrication of LE due to their lower toxicity. The hydrophilicity and lipophilicity is based on HLB scale. The high HLB value of surfactant is used for rapid formation of emulsion droplet. However, during preparation of emulsion, one of the important consideration is the use of greater amount of surfactant concentration (∼40%) may likely to produce toxicity in the ocular tissue [52].
Hydroxypropyl chitosan nail lacquer of ciclopirox-PLGA nanocapsules for augmented in vitro nail plate absorption and onychomycosis treatment
Published in Drug Delivery, 2022
Eman Yahya Gaballah, Thanaa Mohammed Borg, Elham Abdelmonem Mohamed
Ciclopirox (CIX) was purchased from 2A Biotech (Lisle, Illinois, USA). Acid terminated poly-lactide-co-glycolide (PLGA) polymers (50:50 grade 5002 A, molecular weight 17000 g/mol and 50:50 grade 5004 A, molecular weight 44000 g/mol) were kindly provided by Corbion (Gorinchem, Netherlands). Glyceryl monolinoleate (Maisine) was kindly provided by Gattefosse (Saint-Priest, France). Lipoid S75 was kindly provided by Lipoid AG (Schweiz, Switzerland). Span 60 was purchased from ITWCo. (Darmstadt, Germany). Tween 20 was obtained from Sigma-Aldrich (Saint Louis, MO, USA). Hydroxy-propyl chitosan (HPCH) was supplied by Xi’an Imaherb Biotech CO., Ltd (Xi’an Shanxi, China). Cetostearyl alcohol was obtained from Al-Gomhoria Co. (Cairo, Egypt). Acetone, methanol, ethanol, and acetonitrile were purchased from Fisher Scientific (Leicestershire, UK). Amicon® Ultra-4 centrifugal filter units (4 mL, 10 KDa cutoff units), were purchased from Merck CO. (California, USA). Spectrapor® membrane, MW cutoff: 12,000-14,000 Da, was purchased from Spectrum Medical Industries Inc. (Los Angeles, USA). Sabouraud’s dextrose agar was purchased from Oxoid Ltd (Basingstoke, UK). Trichophyton rubrum strains were obtained from Assiut University Moubasher Mycological Center (Assiut, Egypt). All other chemicals were of fine analytical grade.
Related Knowledge Centers
- Cetyl Alcohol
- Emulsion
- Fatty Alcohol
- Surfactant
- Skin
- Stearyl Alcohol
- Stabilizer
- Opacifier
- Foam
- Moisturizer