Publications by authors named "Sandra Costa Fernandez"

3 Publications

  • Page 1 of 1

Nanostructured lipid carriers containing chitosan or sodium alginate for co-encapsulation of antioxidants and an antimicrobial agent for potential application in wound healing.

Int J Biol Macromol 2021 Apr 27;183:668-680. Epub 2021 Apr 27.

Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil. Electronic address:

The high incidence and costs of chronic wounds in the elderly have motivated the search for innovations to improve product performance and the healing process while reducing costs. In this study, bioadhesive nanostructured lipid carriers (NLC) were developed for the co-encapsulation of compounds with antioxidant (α-tocopherol and quercetin) and antimicrobial (tea tree oil) activity for management of wounds. The NLC was produced with shea butter and argan oil, and modified with sodium alginate or chitosan to confer bioadhesive properties. Spherical nanoparticles of ~307-330 nm and zeta potential varying from -21.2 to +11.8 mV were obtained. Thermal analysis demonstrated that the lipid matrix reduced tea tree oil thermal loss (~1.8-fold). Regardless of the type of polysaccharide employed, the NLCs promoted cutaneous localization of antioxidants in damaged (subjected to incision) skin, with a ~74 to 180-fold higher delivery into the skin compared to percutaneous delivery. This result is consistent with the similar bioadhesive properties of chitosan or sodium alginate-modified NLC. Nanoencapsulation of tea tree oil did not preclude its antimicrobial effects against susceptible and resistant strains of S. aureus and P. aeruginosa, while co-encapsulation of antioxidants increased the NLC-induced fibroblasts migration, supporting their potential usefulness for management of wounds.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.04.168DOI Listing
April 2021

Optimization of composition and obtainment parameters of biocompatible nanoemulsions intended for intraductal administration of piplartine (piperlongumine) and mammary tissue targeting.

Int J Pharm 2019 Aug 24;567:118460. Epub 2019 Jun 24.

Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil. Electronic address:

As a new strategy for treatment of ductal carcinoma in situ, biocompatible and bioadhesive nanoemulsions for intraductal administration of the cytotoxic agent piplartine (piperlongumine) were optimized in this study. To confer bioadhesive properties, the nanoemulsion was modified with chitosan or hyaluronic acid. Tricaprylin was selected as the nanoemulsion non-polar phase due to its ability to dissolve larger drug amounts compared to isopropyl myristate and monocaprylin. Use of phosphatidylcholine as sole surfactant did not result in a homogeneous nanoemulsion, while its association with polysorbate 80 and glycerol (in a surfactant blend) led to the formation of nanoemulsions with droplet size of 76.5 ± 1.2 nm. Heating the aqueous phase to 50 °C enabled sonication time reduction from 20 to 10 min. Inclusion of either chitosan or hyaluronic acid resulted in nanoemulsions with similar in vitro bioadhesive potential, and comparable ability to prolong mammary tissue retention (to 120 h) in vivo without causing undesirable histological alterations. Piplartine was stable in both nanoemulsions for 60 days; however, the size of loaded NE-HA was maintained at a similar range for longer periods of time, suggesting that this nanoemulsion may be a stronger candidate for intraductal delivery.
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http://dx.doi.org/10.1016/j.ijpharm.2019.118460DOI Listing
August 2019

Improvement of cutaneous delivery of methylene blue by liquid crystals.

Int J Pharm 2018 Sep 2;548(1):454-465. Epub 2018 Jul 2.

Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Prof. Lineu Prestes 1524, São Paulo, SP, Brazil.

The purpose of this study was to evaluate the effect of composition and characteristics of liquid crystalline phases (LCPs) on cutaneous delivery of methylene blue (MB). LCPs were obtained by mixing Brij97® with water at various ratios; Brij97®:water at 8:2 (F8:2), 7:3 (F7:3), and 6:4 (F6:4) were selected, and MB was incorporated at 0.1%. F8:2 and F7:3 exhibited textures and small angle X-ray scattering (SAXS) patterns corresponding to lamellar phase, whereas F6:4 displayed characteristics of hexagonal phase. All three LCPs were stable for 9 months, and exhibited thixotropic pseudoplastic behaviour. Increasing water content increased viscosity. All three LCPs released less (3.2- to 6.6-fold) MB than control gel (3.0% hydroxyethylcellulose (HEC) + 0.1% MB), demonstrating their ability to sustain release. Despite the lower release, all LCPs improved skin retention of MB at 6 h post-application (1.3- to 2.1-fold) compared to the control gel. Among the LCPs, F8:2-mediated skin retention of MB was more pronounced, followed by F7:3. Consistent with the increased penetration, transepidermal water loss (TEWL) also increased after treatment with the LCPs (2.0-2.8 fold), which suggests their influence on skin barrier. Irritation studies by Hen's Egg Test - Chorioallantoic Membrane (HET-CAM) suggest that F7:3 and F6:4 may be better tolerated by the skin than F8:2.
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http://dx.doi.org/10.1016/j.ijpharm.2018.07.003DOI Listing
September 2018