Novel Starch-Derived Topical Delivery Systems
Andreia Ascenso, Sandra Simões, Helena Ribeiro in Carrier-Mediated Dermal Delivery, 2017
Polymeric nanoparticles (particle size between 1 and 1000 nm) can be classified as nanospheres or nanocapsules. Nanospheres are solid-core structures and nanocapsules are hollow-core structures, as schematized in Fig. 5.9 [44,83,84]. Thus, nanocapsules differ from nanospheres for being a reservoir type of system, while nanospheres are a polymeric matrix system. The core acts as a reservoir for drugs or active substances, or several, which can be dissolved or dispersed. In addition, the core itself can have biological activity or effects (octylmethocinnamate is a UV chemical sunscreen; turmeric oil has antibacterial, antifungal, and antioxidant properties, among others). It is usually composed of triglycerides, an active ingredient, and other chemical substances, such as capric/caprylic triglycerides and sorbitan monostearate or vegetable oils and sorbitan monostearate [85]. On the other hand, surface is directly related to the nature of the polymer, natural or synthetic (ideally non-toxic and biodegradable) and the surfactants used. Usually, synthetic polymers make more reproducible and purer formulations [85–87].
Exploring Potential of Nanocarriers for Therapy of Mycotic Keratitis
Mahendra Rai, Marcelo Luís Occhiutto in Mycotic Keratitis, 2019
Fluconazole was also incorporated into suitable non-phospholipid based elastic vesicular system (Spanlastics) by Kaur and his co-workers (2012) to enhance the bioavailability. The prepared sorbitan (spans)-based elastic (spanlastic vesicles) novel vesicular systems were found to be safe for topical use in a 3-tier safety evaluation (genotoxicity, cytotoxicity, and acute and chronic toxicity studies as per OECD guidelines); although the in-vivo performance of these prepared vesicles was not investigated. Niosome is another non-phospholipid based vesicular system which has gained popularity in ocular drug research (Paul et al. 2010, Maiti et al. 2011). Paradkar and Parmar (2017) also investigated the potential of niosomal in situ gel for ophthalmic delivery in the treatment of mycotic keratitis. It increased the corneal residence time and exhibited drug release upto 24 hours with greater transcorneal permeation across goat cornea. The physical stability of niosomes can be enhanced by formulating liquid crystalline vesicular structures, proniosomes, from non-ionic surfactants having the capability to entrap both hydrophilic and lipophilic drugs. The ocular bioavailability of ketoconazole was effectively increased by entrapping it in mucoadhesive proniosomal gel which exhibited elevated levels of the drug in cornea and aqueous humor of albino rats with absence of redness, inflammation or increased tear production over a period of 24 hours (Abdelbary et al. 2017).
Hands
Robin Lewallen, Adele Clark, Steven R. Feldman in Clinical Handbook of Contact Dermatitis, 2014
Contact dermatitis medicamentosa is also important to consider in the evaluation of hand dermatitis. Many cases of hand dermatitis likely begin as xerosis or in adults with atopic dermatitis manifesting as chronic hand dermatitis. This endogenous barrier disruption then sets the stage for hand dermatitis, which becomes secondarily driven by allergic contact dermatitis to the agents utilized for treatment. In these cases there are more patients who demonstrate palmar (Figure 7.7) or diffuse involvement than seen with glove dermatitis. Both over-the-counter and prescription products need to be considered. Bacitracin is a classic example of this.3 Its use is often seen in the healthcare field and it is also widely applied by patients owing to its availability without prescription. Propylene glycol is another important allergen to consider. It is found in many topical medicaments and is the most common allergen in topical corticosteroid products. It causes both irritant and allergic contact dermatitis. Sorbitan sesquioleate, thiazolinones, lanolin, and formaldehyde-releasing preservatives are other common allergens found in topical corticosteroid vehicles.1
An examination of carbopol hydrogel/organogel bigels of thymoquinone prepared by microwave irradiation method
Published in Drug Development and Industrial Pharmacy, 2020
Evren Algin Yapar, Sakine Tuncay Tanriverdi, Gulsen Aybar Tural, Zinar Pınar Gümüş, Ezgi Turunç, Evren Homan Gokce
Bigels were characterized with different techniques aiming at investigating the material microstructure and the mutual position of the structured phases [31]. Rheological methods were used by Behera et al. [32], Satapathy et al. [33], and Singh et al. [34]. Behera et al. [32] prepared bigels by conventional heating varying the concentrations of PVA and PVP solutions. Sorbitan monopalmitate was dissolved in sun flower oil at 50 °C to form a clear mixture of oil and gelator. Similar to this study, the results of the current study revealed that the viscosity of the bigels increased with the increasing polymer ratio and exhibited a shear – thinning phenomena. Satapathy et al. [33] prepared bigels with sesame oil, tween 80, gelatin, and glutaraldehyde with conventional heating method. Similar to data determined by the mentioned study, bigel formulations prepared were also intact, and not completely deformed.
Quality by design enabled the development of stable and effective oil-in-water emulsions at compounding pharmacy: the case of a sunscreen formulation
Published in Pharmaceutical Development and Technology, 2021
Celia Maria Vargas da Costa Buzzo, Attilio Converti, José Alexsandro da Silva, Alexsandra Conceição Apolinário
The polymer Carbopol® 940 (polyacrylic acid) and the polymeric emulsifier Pemulen™ TR2 (acrylates/C10-30 alkyl acrylate cross-polymer) were acquired from Lubrizol (São Paulo, SP, Brazil). The chelating agent EDTA (disodium ethylenediaminetetraacetate), the antioxidant BHT (butylated hydroxytoluene), and triethanolamine (2,2′,2″-nitrilotriethanol), acting as buffer, chelating agent and surfactant, were purchased from Synth (Diadema, SP, Brazil). The broad spectrum antimicrobial agent Phenonip™, made up of methylparaben, propylparaben, ethylparaben and phenoxyethanol, was acquired from Clariant (Jacareí, SP, Brazil). The non-ionic emulsifier Eumulgin® B2 (Ceteareth-20) used to prepare O/W emulsions was obtained from Croda do Brasil Ltda (Campinas, SP, Brazil). The oil-soluble film former Antaron™ V 216 (VP/hexadecene Copolymer) was purchased from Ashland (Covington, KY, USA). The humectant propylene glycol and the base fluids cyclomethicone and silicone elastomer were acquired from Dow Corning (Hortolândia, SP, Brazil). The O/W emulsifier Emulium® 22 (Tribehenin PEG-20 Esters), organic UV filter, solubilizer and emollient Cocoate™ BG (butylene glycol cocoate) were acquired from Gattefosse (Saint-Priest, France). The co-emulsifier Olivem® 900 (Sorbitan olivate) was obtained from Biovital (São Carlos, SP, Brazil), while the modified natural polymer Dry Flo® (Aluminium Starch Octenylsuccinate), that acts as softening agent, was obtained from Via Farma (São Paulo, SP, Brazil).
A topical formulation containing quercetin-loaded microcapsules protects against oxidative and inflammatory skin alterations triggered by UVB irradiation: enhancement of activity by microencapsulation
Published in Journal of Drug Targeting, 2021
David L. Vale, Renata M. Martinez, Daniela C. Medeiros, Camila da Rocha, Natália Sfeir, Renata F. V. Lopez, Fabiana T. M. C. Vicentini, Waldiceu A. Verri, Sandra R. Georgetti, Marcela M. Baracat, Rúbia Casagrande
Formulation was prepared using: i) the self-emulsifying wax Polawax® (cetostearyl alcohol and polyoxyethylene derived of a fatty acid ester of sorbitan 20 0E) (10%); ii) the emollient caprylic/capric triglyceride (5%); iii) the solubilising agent and moisturiser propylene glycol (6%); iv) the preservative phenonip (0.4%); v) deionised water to complete 100% of formulation. QC (0.5%), QC-loaded microcapsules (adjusted to result in a concentration of 0.5% of quercetin in the final cream) and QC-unloaded microcapsules were dispersed in propylene glycol, and then, under room temperature, added to the formulations. The control formulation without QC was named TFC; formulation with QC for topical administration was named TFQC; topical formulation containing unloaded-microcapsules was named TFuMQ and topical formulation containing QC-loaded microcapsules was named TFcQCMC for an easy differentiation among groups.
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