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Nanocarrier Technologies for Enhancing the Solubility and Dissolution Rate of Api
Published in Debarshi Kar Mahapatra, Sanjay Kumar Bharti, Medicinal Chemistry with Pharmaceutical Product Development, 2019
Ashwini Deshpande, Tulshidas S. Patil
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).
Emulsion Rheology
Published in Laba Dennis, 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.
Advanced Formulation Techniques Including Innovative Materials
Published in Heather A.E. Benson, Michael S. Roberts, Vânia Rodrigues Leite-Silva, Kenneth A. Walters, Cosmetic Formulation, 2019
Bozena Michniak-Kohn, Tannaz Ramezanli, Frank Romanski, Cliff Milow, Kishore Shah
From a regulatory perspective, a typical pharmaceutical formulator utilizes the Inactive Ingredient Database, published on the FDA website (http://www.accessdata.fda.gov/scripts/cder/iig/index.Cfm) as a search reference for excipients previously utilized within approved drugs. The maximum concentration of a given excipient in an approved drug for a specific type of formulation is listed within the database. For example, if a formulator was to use cetostearyl alcohol (Kolliwax® CSA 50), searching for this term in the database would yield numerous listings including use in tablets, creams, foams, lotions, ointments and suppositories. Excipients are all listed with their CAS number and a UNII number for reference, and finally, the maximum concentration of use is listed. As of the writing of this chapter, the listing for cetostearyl alcohol in a topical cream is listed as 11.2% w/w. A formulator may certainly utilize 12, 13, 15% or greater of cetostearyl alcohol in a given cream formulation, but it may invite additional questions regarding safety and efficacy of the formulation, and therefore functions as an artificial ceiling for use at most pharmaceutical companies. This is unfortunately in contrast to the original rationale for publishing of this database. Furthermore, the use of ‘novel excipients’, which are defined as ingredients that have not been previously approved in an NDA or ANDA (abbreviated new drug application), and therefore do not appear in the database, would require further scrutiny form the regulatory authorities for further proof of safety. Again, this is a level of risk most pharmaceutical formulators are unwilling to take. As previously stated, since ingredients are not regulated by the FDA individually but rather as a portion of a filing, a supplier needs to wait for a novel excipient to be utilized and approved within a pharmaceutical company’s drug filing before it will become widely accepted by the industry. This renders innovation on the supplier side extremely challenging.
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.
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].
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
It has been determined that 0.5% LE, which is used as an active ingredient in formulations, does not have any allergic effect even in the ocular application (Amon and Busin 2012). In addition, it was observed that the concentrations at which Compritol® 888 ATO, cetostearyl alcohol, oleic acid, and Pluronic® F68 used in SLN and NLC formulations started to show allergenic effects were 18%, 7%, 10%, and 9% (w/w), respectively (Fukushima et al.1976, Nihant et al.1994, Afanas’ev et al.2008, Aburahma and Badr-Eldin 2014). At the same time, it was stated that the excipients used were substances with Generally Recognise as Safe (GRAS) status (Afanas’ev et al.2008, Aburahma and Badr-Eldin 2014).