21 research outputs found
Smart nano-in-microparticles to tackle bacterial infections in skin tissue engineering
Chronic wounds (resulting from underlying disease, metabolic disorders, infections, trauma, and even tumours)
pose significant health problems. In this work, microparticles, based on polysaccharides (maltodextrin or dextran)
and amino acids, and doped with antibacterial nanoparticles (CuO or ZnO NPs) are designed. Smart nano-inmicroparticles
with a hierarchical 3D structure are developed. The ultimate goal aims at an innovative platform
to achieve skin repair and to manage skin colonization by avoiding infection that could delay and even
impair the healing process. The microparticles are prepared by spray-drying and cross-linked by heating, to obtain
insoluble scaffolds able to facilitate cell proliferation in the wound bed. The nano-in-microparticles are characterized
using a multidisciplinary approach: chemicoâphysical properties (SEM, SEM-EDX, size distribution,
swelling and degradation properties, structural characterization - FTIR, XRPD, SAXS â mechanical properties,
surface zeta potential) and preclinical properties (in vitro biocompatibility and whole-blood clotting properties,
release studies and antimicrobial properties, and in vivo safety and efficacy on murine burn/excisional wound
model) were assessed. The hierarchical 3D nano-in microparticles demonstrate to promote skin tissue repair in a
preclinical study, indicating that this platform deserves particular attention and further investigation will promote
the prototypes translation to clinics.Horizon 2020 Research and Innovation Programme 814607National Science Foundation (NSF) DMR-0520547EC Horizon 2020 program under the SINE2020 projectESRF
65400
Bentonite- and Palygorskite-Based Gels for Topical Drug Delivery Applications
The project was funded by P18-RT-3786 project of Junta de Andalucia (Spain). This
research was partially supported by UniCA-Progetti biennali di Ateneo Finanziati dalla Fondazione
di Sardegna 2018 (CUP F741I19000950007)Bentonite or palygorskite-based hydrogels have recently been suggested as a strategy to
increase bioavailability and control the retention and release of therapeutic candidates. In this work,
clay-based hydrogels loaded with diclofenac acid nanocrystals have been successfully designed and
developed. The aim was to improve diclofenac solubility, its dissolution rate and to enhance its local
bioavailability after topical application. For this purpose, diclofenac acid nanocrystals were prepared
by wet media milling technology and then loaded into inorganic hydrogels based on bentonite
and/or palygorskite. Diclofenac acid nanocrystals were characterized by morphology, size, and
zeta potential. Moreover, rheological behavior, morphology, solid state, release studies, and in vitro
skin penetration/permeation of diclofenac acid nanocrystals-loaded hydrogels were performed.
The hydrogels were characterized by a crystalline structure, and demonstrated that the inclusion
of diclofenac in clay-based hydrogels resulted in an increased thermal stability. The presence of
both palygorskite and bentonite reduced nanocrystal mobility, and consequently its release and
penetration into the skin. On the other hand, bentonite- or palygorskite-based hydrogels revealed
great potential as an alternative strategy to enhance topical bioavailability of DCF nanocrystals,
enhancing their penetration to the deeper skin layers.Junta de Andalucia
P18-RT-3786UniCA-Progetti biennali di Ateneo Finanziati dalla Fondazione di Sardegna 2018
CUP F741I1900095000
Wound Healing Activity of Nanoclay/Spring Water Hydrogels
This project was supported by an FPU grant (MECD), the Spanish research group CTS-946
and the program for international mobility of PhD students (University of Granada). Special thanks to the
Department of Drug Sciences of the University of Pavia (Italy).Background: hydrogels prepared with natural inorganic excipients and spring waters are
commonly used in medical hydrology. Design of these clay-based formulations continues to be a
field scarcely addressed. Safety and wound healing properties of different fibrous nanoclay/spring
water hydrogels were addressed. Methods: in vitro biocompatibility, by means of MTT assay,
and wound healing properties were studied. Confocal Laser Scanning Microscopy was used to
study the morphology of fibroblasts during the wound healing process. Results: all the ingredients
demonstrated to be biocompatible towards fibroblasts. Particularly, the formulation of nanoclays
as hydrogels improved biocompatibility with respect to powder samples at the same concentration.
Spring waters and hydrogels were even able to promote in vitro fibroblasts motility and, therefore,
accelerate wound healing with respect to the control. Conclusion: fibrous nanoclay/spring water
hydrogels proved to be skin-biocompatible and to possess a high potential as wound healing
formulations. Moreover, these results open new prospects for these ingredients to be used in new
therapeutic or cosmetic formulations.German Research Foundation (DFG)Spanish research group
CTS-946Program for international mobility of PhD students (University of Granada
PraziquantelâClays as Accelerated Release Systems to Enhance the Low Solubility of the Drug
Praziquantel is an antiparasitic drug indicated for the treatment of the schistosomiasis
disease. This drug has very low aqueous solubility, requiring high oral doses for its administration
which gives rise to side effects, therapeutic noncompliance and the appearance of resistant forms of the
parasite. Clay minerals, like sepiolite and montmorillonite, are innocuous, non-toxic, biocompatible
and low-cost excipients. Additionally, clays have high adsorbent properties that allow them to
encapsulate drugs in nanometric spaces present in the channels in the case of the sepiolite or between
the layers in the case of the montmorillonite. The interactions between the drug and clay minerals
are studied experimentally with the strategy for preparing interactions products in organic solvents
(ethanol, acetonitrile and dichloromethane) so that the interaction will be more effective and will be
enhanced the aqueous solubility of praziquantel. The results showed that in the interaction products,
the drug interacted with both clay minerals, which produced the loss of the crystallinity of the drug
demonstrated by different techniques. This led to a significant increase in the dissolution rate of the
praziquantel in all the interaction products in the simulated gastrointestinal tract media, except for
the praziquantelâmontmorillonite product prepared in dichloromethane that presented a controlled
release in acid medium. Moreover, in vitro cytotoxicity and cell cycle studies were performed
in the interaction products prepared with ethanol. The interaction product with sepiolite was
biocompatible with the HTC116 line cells, and it did not produce alterations in the cell cycle. However,
interaction products with montmorillonite did not produce cell death, but they showed affectation
and damage of cells in the cell cycle study at the highest concentration tested (20â100 ”M). Therefore,
the different organic solvents used are adequate for the improvement of the biopharmaceutical profile
of praziquantel. Drugâclay interaction products, specifically with sepiolite, showed very promising
results in which new accelerated oral release systems of the praziquantel were obtained.Ministerio de Ciencia e Innovacion government
PCIN-2017-098
FIS2016-77692-C2-2-P
CGL2016-80833-RJunta de Andalucia
RNM1897
P18-RT-378
Clay-Based Hydrogels as Drug Delivery Vehicles of Curcumin Nanocrystals for Topical Application
The poor water solubility of a significant number of active pharmaceutical ingredients (API)
remains one of the main challenges in the drug development process, causing low bioavailability and
therapeutic failure of drug candidates. Curcumin is a well-known Biopharmaceutics Classification
System (BCS) class IV drug, characterized by lipophilicity and low permeability, which hampers
topical bioavailability. Given these premises, the aim of this work was the design and the development
of curcumin nanocrystals and their incorporation into natural inorganic hydrogels for topical
application. Curcumin nanocrystals were manufactured by the wet ball milling technique and then
loaded in clay-based hydrogels. Bentonite and/or palygorskite were selected as the inorganic gelling
agents. Curcumin nanocrystal-loaded hydrogels were manufactured by means of a homogenization
process and characterized with respect to their chemico-physical properties, in vitro release, antioxidant
activity and skin permeation. The results highlighted that the presence of bentonite provided an
increase of curcumin skin penetration and simultaneously allowed its radical scavenging properties,
due to the desirable rheological characteristics, which should guarantee the necessary contact time of
the gel with the skin.UniCA-Progetti biennali di Ateneo Finanziati
dalla Fondazione di Sardegna 2018 (CUP F741I19000950007)P18-RT-3786 project of Junta de Andalucia (Spain
Antioxidant Efficacy and âIn Vivoâ Safety of a Bentonite/Vitamin C Hybrid
The following supporting information can be downloaded at: https:
//www.mdpi.com/article/10.3390/pharmaceutics15041171/s1, S1: LAA/smectites systems: critical
revision; S2: Ophthalmic irritability; S3: Acute dermal toxicity.L-ascorbic acid (LAA), commonly known as vitamin C, is an excellent and recognized
antioxidant molecule used in pharmaceutical and cosmetic formulations. Several strategies have
been developed in order to preserve its chemical stability, connected with its antioxidant power, but
there is little research regarding the employment of natural clays as LAA host. A safe bentonite
(Bent)âwhich was verified by in vivo ophthalmic irritability and acute dermal toxicity assaysâwas
used as carrier of LAA. The supramolecular complex between LAA and clay may constitute an
excellent alternative, since the molecule integrity does not seem to be affected, at least from the point
of view of its antioxidant capacity. The Bent/LAA hybrid was prepared and characterized through
ultraviolet (UV) spectroscopy, X-ray diffraction (XRD), infrared (IR) spectroscopy, thermogravimetric
analysis (TG/DTG) and zeta potential measurements. Photostability and antioxidant capacity tests
were also performed. The LAA incorporation into Bent clay was demonstrated, as well as the drug
stability due to the Bent photoprotective effect onto the LAA molecule. Moreover, the antioxidant
capacity of the drug in the Bent/LAA composite was confirmed.France Embassy in CubaErasmus+ scholarshipTWAS
00-360 RG/CHE/LA,
07-016 RG/CHE/LAPN211LH008-027,
PN223LH010-01
Hybrid Lipid/Clay Carrier Systems Containing Annatto Oil for Topical Formulations
Financial support for this research was provided by the Coordination of Improvement of Higher-Level Personnel-Brazil (CAPES)-02817/09. RMB and FNR acknowledge fellowships from National Council for Scientific and Technological Development CNPq (Brazil). This research also was financially supported by Junta de Andalucia, under the project reference PT18 RT 3786.Nanocomposites formed by clay and lipid carriers (NLCs) show a high potential for providing
controlled release and specific delivery of bioactive molecules and have recently gained attention
in the pharmaceutical sector due to their ability to transport hydrophilic and hydrophobic drugs.
Recent studies have recognized the biological activity of the oil of Bixa orellana L. (AO) with regards
to its healing, antioxidant, antibacterial, and anti-leishmanial properties. Therefore, the purpose
of this study is the preparation and characterization of hybrid systems based on lipid nanocarriers
and laponite for the delivery of AO. NLCs were prepared by the fusion-emulsification method,
using cetyl palmitate (CP) or myristyl myristate (MM), AO, and Poloxamer 188. The morphology,
hydrodynamic diameters, zeta potential (ZP), polydispersity index (PDI), thermal analysis, X-ray
diffraction analysis (XRD), viscosity behavior, and cytotoxicity testing of the hybrid systems were
performed. The thermal study and X-ray diffraction analyses (XRD) revealed polymorphic structural
changes compatible with the amorphization of the material. Rheological assays highlighted a typical
pseudoplastic behavior in all systems (MM and CP with LAP). The hybrid systemsâ morphology, size
diameters, and PDIs were similar, preset spherical and monodisperse structures ( 200 nm; <0.3),
without significant change up to sixty days. The ZP values differed from each other, becoming higher
with increasing AO concentration. XEDS spectra and elemental X-ray maps show peaks of lipids
(organic components, C and O) and inorganic components O, Mg, and Si. All samples showed cell
viability above 60%. The results indicated a stable, biocompatible hybrid system that can be an
alternative for topical application.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) 02817/09Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ)Junta de Andalucia PT18 RT 378
Investigation into Brazilian Palygorskite for Its Potential Use as Pharmaceutical Excipient: Perspectives and Applications
Palygorskite is an aluminum and magnesium silicate characterized by its fibrous morphology, providing it with great versatility in industrial applications, including pharmaceuticals. Although most of the reserves are in the United States, in recent years occurrences of commercially exploited deposits in Brazil have been recorded, mainly in the countryâs northeast region. This has motivated this study, which analyzes raw Brazilian palygorskite compared to a commercial sample (PharmasorbÂź colloidal) to demonstrate its pharmaceutical potential. The chemical and mineral composition of the samples were evaluated for surface properties, granulometry, morphology, crystallography, thermal analysis, and spectroscopy. Raw palygorskite presented 67% purity, against 74% for PharmasorbÂź colloidal. The percentage purity relates to the presence of contaminants, mainly carbonates and quartz (harmless under conventional conditions of pharmaceutical use). Furthermore, it was possible to confirm the chemical composition of these phyllosilicates, formed primarily of silicon, aluminum, and magnesium oxides. The crystallographic and spectroscopic profiles were consistent in both samples, showing characteristic peaks for palygorskite (2Ξ = 8.3°) and bands attributed to fibrous phyllosilicates below 1200 cmâ1, respectively. The thermal analysis allowed the identification of the main events of palygorskite, with slight differences between the evaluated samples: loss of water adsorbed onto the surface (~85 °C), removal of water contained in the channels (~200 °C), coordinated water loss (~475 °C), and, finally, the dehydroxylation (>620 °C). The physicochemical characteristics of raw palygorskite align with pharmacopeial specifications, exhibiting a high specific surface area (122 m2/g), moderately negative charge (â13.1 mV), and compliance with the required limits for heavy metals and arsenic. These favorable technical attributes indicate promising prospects for its use as a pharmaceutical ingredient in the production of medicines and cosmetics.CAPES, grant number 88887.131333/2016-0
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Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9â27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6â16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2â1.8), stage II (OR 1.6; 95% CI 1.4â1.9), and stage III or worse (OR 2.8; 95% CI 2.3â3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
The original version of this article unfortunately contained a mistake