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Physical and Technological Modulation of Topical and Transdermal Drug Delivery
Published in Marc B. Brown, Adrian C. Williams, The Art and Science of Dermal Formulation Development, 2019
Marc B. Brown, Adrian C. Williams
Many of the preparation procedures and principles described above apply to niosomes which are essentially liposomes prepared primarily from non-ionic surfactants. As with conventional liposomes prepared from phospholipids, the properties of niosomes can be modified by incorporation of other excipients, such as cholesterol, into the membrane and they can possess one or more lipid bilayers encapsulating an aqueous core. A diverse range of materials have been used to form niosomes such as sucrose ester surfactants and polyoxyethylene alkyl ether surfactants; many non-ionic surfactants have relatively low toxicities, cause less damage to skin membranes than ionic surfactants and, in the case of sucrose esters, are readily biodegraded.
Chemistry and Biology of Monoglycerides in Cosmetic Formulations
Published in Eric Jungermann, Norman O.V. Sonntag, Glycerine, 2018
The above statement concerning structure-function relationships is true as far as specific organisms and cosmetic products are concerned. However, the effects of monoglycerides can be neutralized by a variety of polymers, including starch and protein, and because binding seems to follow biological activity, several Japanese workers have reported that the volatile fatty acids esters (C8, C10) were more active than the higher (C12) homologs [52, 53]. These reports, negating the generalizations found, must be viewed as exceptions. Beuchat [54] and Shibasaki [49] have supported the finding that the lauric acid derivative is the most active monoglyceride even in the presence of other complexing stuffs. Beuchat [54] compared the effects of glycerides, sucrose esters, benzoate, sorbic acid, and potassium sorbate against Vibrio parahaemoiyticus. His results again indicated that the C12 monoglyceride was more active than lower (C8, C10) or higher (C14) chain length derivatives. Also, the low MIC value for monolaurin (≤ 5 μg/ml) indicated it to be more effective than sodium benzoate (300 μg/ml) or sorbic acid (70 μg/ml).
Intestinal permeation enhancers to improve oral bioavailability of macromolecules: reasons for low efficacy in humans
Published in Expert Opinion on Drug Delivery, 2021
Sam Maher, Caroline Geoghegan, David J. Brayden
Use of semi-solids such as Tween 80 and C12E9, as well as soft solids such as sucrose esters also present challenges for oral formulation. It is difficult to create a uniform suspension of macromolecules in a semi-solid PE. The semi-solid can be melted to facilitate better dispersion of the macromolecule (either as a solution or suspension) provided it is stable at the melting point of the semi-solid (e.g. 44°C for GelucireTM 44/14). An alternative is to freeze-dry an aqueous dispersion of PE and macromolecule. PEs that are waxy soft solids may be admixed with macromolecule, but heat and moisture increases cohesion, which reduces flowability and may impede optimal mixing. It may be feasible to incorporate these materials into capsules, but waxy malleable solids are difficult to incorporate into tablets.
Exploring the mucoadhesive behavior of sucrose acetate isobutyrate: a novel excipient for oral delivery of biopharmaceuticals
Published in Drug Delivery, 2019
Stine Harloff-Helleberg, Lies A. L. Fliervoet, Mathias Fanø, Mechthild Schmitt, Maxim Antopolski, Arto Urtti, Hanne Mørck Nielsen
As presence of biological fluids affects the rheological behavior of gel-based systems (Chang et al., 2002), the rheological properties of SAIB DDS were investigated during 72 h immersion in MES and SSIF at 37 °C (Figure 2(C)). Additionally, the amount of volatile matter (i.e. amount of substance evaporated) in SAIB DDS was determined after up to 48 h immersion in MES or SSIF buffer. From Figure 2(C), it is evident that immersion in MES or SSIF buffer (both pH 6.5) resulted in an increase of G′ as a function of time corresponding to a loss of volatile matter from the SAIB DDS already after 1 h immersion in buffer (Figure 2(D)); the same behavior as observed after 7 days storage at 37 °C (Figure 2(A)). This supports the previously stated hypothesis that irreversible coalescence of the ethanol phase is occurring. Interestingly, the increase in G′ at 1 rad/s and loss of volatile matter occurred in a delayed manner for the SAIB DDS immersed in the SSIF compared to MES buffer. It is previously reported that addition of lipophilic co-surfactants, such as the ones present in SSIF, can penetrate into the palisade layer of sucrose esters, hence induce swelling of the system (Rodriguez-Abreu et al., 2005). Such swelling allows for increased hydration of the SAIB DDS, thus increasing the percentage of volatile matter. This finding is highly interesting, as hydration of the delivery system is closely related to mucoadhesion, as well as to the diffusion of bioactive compounds through the intestinal mucosa (Peppas & Buri, 1985). SAIB DDS is thus believed to have highly interesting properties as DDS targeting the intestinal mucus due to high spreadability, swelling and consequently mucoadhesive behavior.