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1.
ACS Biomater Sci Eng ; 10(5): 3006-3016, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38640484

RESUMEN

Soft implantable devices are crucial to optimizing form and function for many patients. However, periprosthetic capsule fibrosis is one of the major challenges limiting the use of implants. Currently, little is understood about how spatial and temporal factors influence capsule physiology and how the local capsule environment affects the implant structure. In this work, we analyzed breast implant capsule specimens with staining, immunohistochemistry, and real-time polymerase chain reaction to investigate spatiotemporal differences in inflammation and fibrosis. We demonstrated that in comparison to the anterior capsule against the convex surface of breast implants, the posterior capsule against the flat surface of the breast implant displays several features of a dysregulated foreign body reaction including increased capsule thickness, abnormal extracellular remodeling, and infiltration of macrophages. Furthermore, the expression of pro-inflammatory cytokines increased in the posterior capsule across the lifespan of the device, but not in the anterior capsule. We also analyzed the surface oxidation of breast explant samples with XPS analysis. No significant differences in surface oxidation were identified either spatially or temporally. Collectively, our results support spatiotemporal heterogeneity in inflammation and fibrosis within the breast implant capsule. These findings presented here provide a more detailed picture of the complexity of the foreign body reaction surrounding implants destined for human use and could lead to key research avenues and clinical applications to treat periprosthetic fibrosis and improve device longevity.


Asunto(s)
Implantes de Mama , Fibrosis , Reacción a Cuerpo Extraño , Propiedades de Superficie , Implantes de Mama/efectos adversos , Humanos , Reacción a Cuerpo Extraño/patología , Reacción a Cuerpo Extraño/metabolismo , Reacción a Cuerpo Extraño/inmunología , Femenino , Siliconas/química , Geles de Silicona/efectos adversos , Citocinas/metabolismo , Inflamación/patología , Inflamación/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología
2.
J Am Soc Mass Spectrom ; 35(5): 829-833, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38564189

RESUMEN

A new approach using orthogonal analytical techniques is developed for chemical identification. High resolution mass spectrometry and infrared ion spectroscopy are applied through a 5-level confidence paradigm to demonstrate the effectiveness of nontargeted workflow for the identification of hazardous organophosphates. Triphenyl phosphate is used as a surrogate organophosphate for occupational exposure, and silicone wristbands are used to represent personal samplers. Spectral data of a target compound is combined with spectral data of the sodium adduct and quantum chemical calculations to achieve a confirmed identification. Here, we demonstrate a nontargeted workflow that identifies organophosphate exposure and provides a mechanism for selecting validated methods for quantitative analyses.


Asunto(s)
Exposición Profesional , Siliconas , Espectrofotometría Infrarroja , Flujo de Trabajo , Exposición Profesional/análisis , Siliconas/química , Humanos , Espectrofotometría Infrarroja/métodos , Espectrometría de Masas/métodos , Monitoreo del Ambiente/métodos , Organofosfatos/análisis , Organofosfatos/química
3.
Biofouling ; 40(2): 177-192, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38465991

RESUMEN

Silicone materials are widely used in fouling release coatings, but developing eco-friendly protection via biosourced coatings, such as polyhydroxyalcanoates (PHA) presents a major challenge. Anti-bioadhesion properties of medium chain length PHA and short chain length PHA films are studied and compared with a reference Polydimethylsiloxane coating. The results highlight the best capability of the soft and low-roughness PHA-mcl films to resist bacteria or diatoms adsorption as compared to neat PDMS and PHBHV coatings. These parameters are insufficient to explain all the results and other properties related to PHA crystallinity are discussed. Moreover, the addition of a low amount of PEG copolymers within the coatings, to create amphiphilic coatings, boosts their anti-adhesive properties. This work reveals the importance of the physical or chemical ambiguity of surfaces in their anti-adhesive effectiveness and highlights the potential of PHA-mcl film to resist the primary adhesion of microorganisms.


Asunto(s)
Diatomeas , Polihidroxialcanoatos , Biopelículas , Siliconas/química , Adsorción
4.
Pac Symp Biocomput ; 29: 170-186, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38160278

RESUMEN

Wearable silicone wristbands are a rapidly growing exposure assessment technology that offer researchers the ability to study previously inaccessible cohorts and have the potential to provide a more comprehensive picture of chemical exposure within diverse communities. However, there are no established best practices for analyzing the data within a study or across multiple studies, thereby limiting impact and access of these data for larger meta-analyses. We utilize data from three studies, from over 600 wristbands worn by participants in New York City and Eugene, Oregon, to present a first-of-its-kind manuscript detailing wristband data properties. We further discuss and provide concrete examples of key areas and considerations in common statistical modeling methods where best practices must be established to enable meta-analyses and integration of data from multiple studies. Finally, we detail important and challenging aspects of machine learning, meta-analysis, and data integration that researchers will face in order to extend beyond the limited scope of individual studies focused on specific populations.


Asunto(s)
Monitoreo del Ambiente , Dispositivos Electrónicos Vestibles , Humanos , Biología Computacional , Análisis de Datos , Monitoreo del Ambiente/métodos , Siliconas/química
5.
Chemosphere ; 339: 139778, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37567263

RESUMEN

Silicone wristbands were utilized as personal passive samplers in a sub-cohort of 92 women, who participated in New York University Children's Health and Environment Study, to assess exposure to semi-volatile organic compounds (SVOCs). Wristbands were analyzed for 77 SVOCs, including halogenated and non-halogenated organophosphate esters (OPEs), polychlorinated biphenyls (PCBs), pesticides, phthalates, and brominated flame retardants (BFRs) (e.g. polybrominated diphenyl ethers (PBDEs)). This study aimed to look for patterns in chemical exposure utilizing participant demographics gathered from a questionnaire, and chemical exposure data across multiple timepoints during pregnancy. Analysis focused on 27 compounds detected in at least 80% of the wristbands examined. The chemicals detected most frequently included two pesticides, eight phthalates, one phthalate alternative, seven BFRs, and nine OPEs, including isopropylated and tert-butylated triarylphosphate esters (ITPs and TBPPs). Co-exposure to different SVOCs was most prominent in compounds that were within the same chemical class or were used in similar consumer applications such as phthalates and OPEs, which are often used as plasticizers. Pre-pregnancy BMI was positively associated with multiple compounds, and there were both positive and negative associations between women's parity and SVOC exposure. Outdoor temperature was not correlated with the wristband concentrations over a five-day sampling period. Lastly, significant and moderately high Intraclass Correlation Coefficient (ICC) (0.66-0.84) values for phthalate measurementsacross pregnancy indicate chronic exposure and suggest that using wristbands during one sampling period may reliably predict exposure. However, multiple sampling periods may be necessary to accurately determine indoor exposure to other SVOCs including OPEs and BFRs.


Asunto(s)
Retardadores de Llama , Plaguicidas , Compuestos Orgánicos Volátiles , Niño , Humanos , Femenino , Embarazo , Siliconas/química , Monitoreo del Ambiente , Compuestos Orgánicos Volátiles/análisis , Organofosfatos/análisis , Plaguicidas/análisis , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis , Ésteres
6.
Colloids Surf B Biointerfaces ; 230: 113486, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37572399

RESUMEN

Infections associated with the surfaces of medical devices represent a critical problem due to biofilm formation and the growing resistance towards antibacterial drugs. This is particularly relevant in commonly used invasive devices such as silicone-based ones where a demand for alternative antibiofilm surfaces is increasing. In this work, an antimicrobial chitosan-biosurfactant hydrogel mesh was produced by 3D-printing. The 3D structure was designed to coat polydimethylsiloxane-based medical devices for infection prevention. Additionally, the porous 3D structure allows the incorporation of customized bioactive components. For this purpose, two biosurfactants (surfactin and sophorolipids) were biosynthesized and tested for their antimicrobial activity. In addition, the printing of surfactant-chitosan-based coatings was optimized, and the resulting 3D structures were characterized (i.e., wettability, FTIR-ATR, antimicrobial activity, and biocompatibility). Compared with surfactin, the results showed a better yield and higher antibacterial activity against Gram-positive bacteria for sophorolipids (SLs). Thus, SLs were used to produce chitosan-based 3D-printed coatings. Overall, the SLs-impregnated coatings showed the best antibacterial activity against Staphylococcus aureus planktonic bacteria (61 % of growth inhibition) and antibiofilm activity (2 log units reduction) when compared to control. Furthermore, concerning biocompatibility, the coatings were cytocompatible towards human dermal fibroblasts. Finally, the coating presented a mesh suitable to be filled with a model bioactive compound (i.e., hyaluronic acid), paving the way to be used for customized therapeutics.


Asunto(s)
Antiinfecciosos , Quitosano , Humanos , Siliconas/química , Quitosano/farmacología , Quitosano/química , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus , Impresión Tridimensional , Materiales Biocompatibles Revestidos/química , Biopelículas
7.
J Biomater Sci Polym Ed ; 34(17): 2400-2410, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37584778

RESUMEN

The physical and chemical properties of contact lenses (CLs) differ significantly from one another. This is already covered by the FDA classification, which divides soft lenses into groups and subgroups for additional characteristics. The differences relate to both the interior and surface of the lens. Several differences in the surface characteristics of individual contact lenses have been studied and demonstrated to date. However, one of their fundamental physical properties, that is light reflection or, quantitatively, reflectance has not been compared. This paper describes the surface differences of a range of silicone-hydrogel (SiHy) lenses using reflectance confocal microscopy. It shows the relationship between the amount of light reflected from the lens surface and the material parameters. Common SiHy lens materials were used in the study, including two lenses with surface modifications. Light incident at the interface between two media (phosphate-buffered saline and lens) with different refractive indices is partially reflected. The normalized results show significant differences between the reflection signals (1 vs 0.07), and that they are not correlated with the refractive index (R2 = 0.5536). For the water content (%H2O), a general trend was observed that the higher the %H2O, the lower the reflection signal is (R2 = 0.8105). The reflection signal and surface modulus show the best correlation. (R2 = 0.9883). The proposed CLs analysis method, using reflectance confocal microscopy, provides data to differentiate between lenses with and without surface modifications.


Asunto(s)
Lentes de Contacto Hidrofílicos , Hidrogeles , Hidrogeles/química , Siliconas/química , Agua , Microscopía Confocal , Hidrogel de Polietilenoglicol-Dimetacrilato
8.
Eur J Pharm Biopharm ; 187: 184-195, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37142129

RESUMEN

Many pharmaceutical manufacturing units utilize pre-sterilized ready-to fill primary containers for parenterals. The containers may have been sterilized by the supplier via autoclavation. This process can change the physicochemical properties of the material and the subsequent product stability. We studied the impact of autoclavation on baked on siliconized glass containers for biopharmaceuticals. We characterized the container layers of different thickness before and after autoclavation for 15 min at 121 °C and 130 °C. Furthermore, we analyzed the adsorption of a mAb to the silicone layer and subjected filled containers to 12 weeks storage at 40 °C monitoring functionality and subvisible particle formation of the product. Autoclavation turned the initially homogenous silicone coating into an incoherent surface with uneven microstructure, changed surface roughness and energy, and increased protein adsorption. The effect was more pronounced at higher sterilization temperatures. We did not observe an effect of autoclavation on stability. Our results did not indicate any concerns for autoclavation at 121 °C for safety and stability of drug/device combination products using baked-on siliconized glass containers.


Asunto(s)
Productos Biológicos , Siliconas/química , Vidrio/química , Jeringas , Calor , Embalaje de Medicamentos
9.
Environ Res ; 222: 115412, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36736760

RESUMEN

It has been suggested that domestic animals can serve as sentinels for human exposures. In this study our objectives were to demonstrate that i) silicone collars can be used to measure environmental exposures of (domestic) animals, and that ii) domestic animals can be used as sentinels for human residential exposure. For this, we simultaneously measured polycyclic aromatic hydrocarbons (PAHs) using silicone bands worn by 30 pet cats (collar) and their owner (wristband). Collars and wristbands were worn for 7 days and analyzed via targeted Gas Chromatography-Mass Spectrometry (GC-MS). Demographics and daily routines were collected for humans and cats. Out of 16 PAHs, 9 were frequently detected (>50% of samples) in both wristbands and collars, of which Phenanthrene and Fluorene were detected in all samples. Concentrations of wristbands and collars were moderately correlated for these 9 PAHs (Median Spearman's r = 0.51 (range 0.16-0.68)). Determinants of PAH concentrations of cats and humans showed considerable overlap, with vacuum cleaning resulting in higher exposures and frequent changing of bed sheets in lower exposures. This study adds proof-of-principle data for the use of silicone collars to measure (domestic) animal exposure and shows that cats can be used as sentinels for human residential exposure.


Asunto(s)
Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos , Humanos , Gatos , Animales , Monitoreo del Ambiente/métodos , Siliconas/química , Exposición a Riesgos Ambientales/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Animales Domésticos
10.
Adv Mater ; 35(18): e2210034, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36739591

RESUMEN

Driven by regulatory authorities and the ever-growing demands from industry, various artificial tissue models have been developed. Nevertheless, there is no model to date that is capable of mimicking the biomechanical properties of the skin whilst exhibiting the hydrophilicity/hydrophobicity properties of the skin layers. As a proof-of-concept study, tissue surrogates based on gel and silicone are fabricated for the evaluation of microneedle penetration, drug diffusion, photothermal activity, and ultrasound bioimaging. The silicone layer aims to imitate the stratum corneum while the gel layer aims to mimic the water-rich viable epidermis and dermis present in in vivo tissues. The diffusion of drugs across the tissue model is assessed, and the results reveal that the proposed tissue model shows similar behavior to a cancerous kidney. In place of typical in vitro aqueous solutions, this model can also be employed for evaluating the photoactivity of photothermal agents since the tissue model shows a similar heating profile to skin of mice when irradiated with near-infrared laser. In addition, the designed tissue model exhibits promising results for biomedical applications in optical coherence tomography and ultrasound imaging. Such a tissue model paves the way to reduce the use of animals testing in research whilst obviating ethical concerns.


Asunto(s)
Epidermis , Piel , Animales , Ratones , Piel/diagnóstico por imagen , Ultrasonografía/métodos , Siliconas/química
11.
J Biomater Sci Polym Ed ; 34(11): 1539-1558, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36651136

RESUMEN

Tissues are highly three-dimensional structure complexes composed of different cell types and their interactions. One of the main challenges in tissue engineering is the inability to produce large, highly perfused scaffolds in which cells can grow at a high cell density and viability. Poly(dimethyl siloxane) (PDMS) is used as a flexible, biocompatible cell culture substrate with tunable mechanical properties. However, its fragility and hydrophobicity still pose a challenge. Here, we present a new strategy for the three-step one-pot synthesis of novel biocompatible hydrophilic copolymers containing siloxane units. In the first step, free radical copolymerization of acrylic acid (AA), butyl methacrylate (BMA), and 2-hydroxyethyl methacrylate (HEMA) was carried out in dioxane (DO) solution in the presence of 2,2'-azodiisobutyronitrile (AIBN). In the second step, the copolymers were modified with diepoxypropoxypropyl-terminated polydimethylsiloxane (DE-PDMS), and in the third step, the copolymers were additionally modified with glycidyl methacrylate (GMA). The modified copolymers were characterized by FTIR, NMR spectroscopy and elemental analysis. Films of modified copolymers were prepared by UV curing. SEM studies revealed microphase separated morphology with distribution of PDMS domains. The mechanical properties of the films depended on the amount of incorporated silicone modifier. The films were more hydrophilic than PDMS films. All novel copolymers showed high biocompatibility.


Asunto(s)
Materiales Biocompatibles , Siloxanos , Materiales Biocompatibles/química , Polímeros/química , Siliconas/química , Interacciones Hidrofóbicas e Hidrofílicas
12.
Biofouling ; 38(9): 876-888, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36503292

RESUMEN

The biological impact of chemical formulations used in various coating applications is essential in guiding the development of new materials that directly contact living organisms. To illustrate this point, an investigation addressing the impact of chemical compositions of polydimethylsiloxane networks on a common platform for foul-release biofouling management coatings was conducted. The acute toxicity of network components to barnacle larvae, the impacts of aqueous extracts of crosslinker, silicones and organometallic catalyst on trypsin enzymatic activity, and the impact of assembled networks on barnacle adhesion was evaluated. The outcomes of the study indicate that all components used in the formulation of the silicone network alter trypsin enzymatic activity and have a range of acute toxicity to barnacle larvae. Also, the adhesion strength of barnacles attached to PDMS networks correlates to the network formulation protocol. This information can be used to assess action mechanisms and risk-benefit analysis of PDMS networks.


Asunto(s)
Incrustaciones Biológicas , Thoracica , Animales , Tripsina , Biopelículas , Incrustaciones Biológicas/prevención & control , Siliconas/química
13.
Expert Opin Drug Deliv ; 19(11): 1539-1548, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36242524

RESUMEN

OBJECTIVES: Olanzapine (OZP) is a safe and effective atypical antipsychotic drug used in treating schizophrenia and bipolar disorders. The dosage forms currently on the market for OZP are administered via oral or intramuscular routes. However, there are many problems associated with oral and intramuscular routes of drug administration. Thus, our aim was to develop a drug-in-adhesive transdermal delivery system (TDS) that can deliver OZP for 3 days. METHODS: We determined passive permeation, effect of oleic acid as chemical enhancer, and delivery of OZP across different skin types. Based on preliminary studies and saturation solubility of OZP in different pressure-sensitive adhesives (PSAs), we formulated and characterized solution-based TDS in acrylate PSA and suspension-based TDS in silicone and PIB PSA, with oleic acid as chemical enhancer. RESULTS: Acrylate solution-based TDS, silicone, and PIB suspension-based TDS delivered 58.97 ± 6.59 µg/sq.cm, 129.34 ± 16.59 µg/sq.cm, and 245.00 ± 2.51 µg/sq.cm, respectively, using in vitro permeation testing. PIB PSA suspension-based TDS met the 3 days desired target delivery. Skin irritation testing using In vitro EpiDermTM skin irritation test (EPI-200-SIT) kit found PIB TDS to be nonirritant. CONCLUSION: The PIB PSA suspension-based TDS could serve as a potentially effective transdermal delivery system for olanzapine.


Asunto(s)
Adhesivos , Absorción Cutánea , Humanos , Masculino , Acrilatos/metabolismo , Acrilatos/farmacología , Adhesivos/química , Adhesivos/metabolismo , Adhesivos/farmacología , Administración Cutánea , Sistemas de Liberación de Medicamentos , Olanzapina/metabolismo , Olanzapina/farmacología , Ácido Oléico/metabolismo , Ácido Oléico/farmacología , Permeabilidad , Preparaciones Farmacéuticas/metabolismo , Antígeno Prostático Específico/metabolismo , Antígeno Prostático Específico/farmacología , Siliconas/química , Piel/metabolismo , Parche Transdérmico
14.
Biomacromolecules ; 23(11): 4547-4561, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36130109

RESUMEN

A type of ultrathin films has been developed for suppressing capsule formation induced by medical silicone implants and hence reducing the inflammation response to such formation and the differentiation to myofibroblasts. The films were each fabricated from hyaluronic acid (HA) and modified ß-cyclodextrin (Mod-ß-CyD) polymer which was synthesized with a cyclodextrin with partially substituted quaternary amine. Ultrathin films comprising HA and Mod-ß-CyD or poly(allylamine hydrochloride) (PAH) were fabricated by using a layer-by-layer dipping method. The electrostatic interactions produced from the functional groups of Mod-ß-CyD and HA influenced the surface morphology, wettability, and bio-functional activity of the film. Notably, medical silicone implants coated with PAH/HA and Mod-ß-CyD multilayers under a low pH condition exhibited excellent biocompatibility and antibiofilm and anti-inflammation properties. Implantation of these nanoscale film-coated silicones showed a reduced capsular thickness as well as reduced TGFß-SMAD signaling, myofibroblast differentiation, biofilm formation, and inflammatory response levels. We expect our novel coating system to be considered a strong candidate for use in various medical implant applications in order to decrease implant-induced capsule formation.


Asunto(s)
Infecciones Bacterianas , beta-Ciclodextrinas , Humanos , Ácido Hialurónico/química , Polímeros , Siliconas/química
15.
Int J Pharm ; 627: 122216, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36179929

RESUMEN

Peristaltic pumping has been identified as a cause for protein particle formation during manufacturing of biopharmaceuticals. To give advice on tubing selection, we evaluated the physicochemical parameters and the propensity for tubing and protein particle formation using a monoclonal antibody (mAb) for five different tubings. After pumping, particle levels originating from tubing and protein differed substantially between the tubing types. An overall low shedding of tubing particles by wear was linked to low surface roughness and high abrasion resistance. The formation of mAb particles upon pumping was dependent on the tubing hardness and surface chemistry. Defined stretching of tubing filled with mAb solution revealed that aggregation increased with higher strain beyond the breaking point of the protein film adsorbed to the tubing wall. This is in line with the decrease in protein particle concentration with increasing tubing hardness. Furthermore, material composition influenced particle formation propensity. Faster adsorption to materials with higher hydrophobicity is suspected to lead to a higher protein film renewal rate resulting in higher protein particle counts. Overall, silicone tubing with high hardness led to least protein particles during peristaltic pumping. Results from this study emphasize the need of proper tubing selection to minimize protein particle generation upon pumping.


Asunto(s)
Anticuerpos Monoclonales , Productos Biológicos , Falla de Equipo , Adsorción , Anticuerpos Monoclonales/química , Siliconas/química
16.
Environ Res ; 214(Pt 3): 113981, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35952739

RESUMEN

Silicone wristbands act as passive environmental samplers capable of detecting and measuring concentrations of a variety of chemicals. They offer a noninvasive method to collect complex exposure data in large-scale epidemiological studies. We evaluated the inter-method reliability of silicone wristbands and urinary biomarkers in the New Hampshire Birth Cohort Study. A subset of study participants (n = 96) provided a urine sample and wore a silicone wristband for 7 days at approximately 12 gestational weeks. Women were instructed to wear the wristbands during all their normal activities. Concentrations of urinary compounds and metabolites in the urine and parent compounds in wristbands were compared. High detection rates were observed for triphenyl phosphate (76.0%) and benzophenone (78.1%) in wristbands, although the distribution of corresponding urinary concentrations of chemicals did not differ according to whether chemicals were detected or not detected in wristbands. While detected among only 8.3% of wristbands, median urinary triclosan concentrations were higher among those with triclosan detected in wristbands (9.04 ng/mL) than without (0.16 ng/mL). For most chemicals slight to fair agreement was observed across exposure assessment methods, potentially due to low rates of detection in the wristbands for chemicals where observed urinary concentrations were relatively low as compared to background concentrations in the general population. Our findings support the growing body of research in support of deploying silicone wristbands as an important exposure assessment tool.


Asunto(s)
Exposoma , Retardadores de Llama , Triclosán , Biomarcadores , Estudios de Cohortes , Monitoreo del Ambiente/métodos , Femenino , Retardadores de Llama/análisis , Humanos , Embarazo , Reproducibilidad de los Resultados , Siliconas/química
17.
Int J Pharm ; 625: 122111, 2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-35973590

RESUMEN

Silicones, more specifically those of the polydimethylsiloxane type, have been widely used in the pharmaceutical industry for decades, particularly in topical applications. In the dermatological field, in addition to provide undeniable textural and sensory benefits, they can play important functions in the physicochemical properties, stability and biopharmaceutical behavior of these formulations. However, despite the notable advances that can be attributed to the family of silicones, the reputation of these compounds is quite bad. Indeed, silicones, even if they derive from sand, are synthetic compounds. Moreover, they are not biodegradable. They flow into our wastewater and oceans, accumulating in the fauna and flora. This obviously raises many concerns in the common imagination. Do silicones represent a danger for our environment? Should the human species worry about long term toxic effects? Are the claimed benefits really that important? After exploring the various applications of silicone excipients in topical dermatological formulations with a special focus on recent advances which open breathtaking prospects for dermatological applications, this paper shed light on the specific challenges involved in preparation of silicone-based drug as well as, the in vivo behavior of these polymers, the toxicological and environmental risks associated with their application.


Asunto(s)
Química Farmacéutica , Siliconas , Portadores de Fármacos/química , Composición de Medicamentos , Excipientes/química , Humanos , Siliconas/química
18.
Int J Cosmet Sci ; 44(5): 514-529, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35815903

RESUMEN

OBJECTIVE: Nowadays, the use of silicones in cosmetic formulation is still controversial, given that "natural" or "biodegradable" components are preferred. Often, the exclusion and/or the discrimination of these excipients from cosmetic field are unmotivated because all things cannot be painted with the same brush. Hence, we want to bring to light and underline the advantages of including silicones in cosmetic emulsions, refuting and debunking some myths related to their use. METHODS: Silicone-free and silicone-based emulsions were obtained within an easy homogenization process. Droplet size distribution was assessed by laser diffraction particle size analyser Mastersizer 2000™, and by optical microscopy. The long-time stability profiles were investigated thanks to the optical analyser Turbiscan® Lab Expert. Diffusing wave spectroscopy (DWS) by Rheolaser Master™ and frequency sweep measurements by Kinexus® Pro Rotational Rheometer were carried out to assess a full rheological characterization. In vivo studies were carried out by the evaluation of Trans Epidermal Water Loss (TEWL) over time on healthy human volunteers. A skin feeling rating was collected from the same volunteers by questionnaire. RESULTS: From size distribution analysis, a better coherence of data appeared for silicone-based emulsion, as the size of the droplets was kept unchanged after 1 month, as well as the uniformity parameter. Morphological investigation confirmed a homogenous droplet distribution for both samples. Silicones enhanced the viscosity, compactness and strength of the cream, providing a suitable stability profile both at room temperature and when heated at 40°C. The solid-like viscoelastic behaviour was assessed in the presence of dynamic oscillatory stresses. The monitoring of TEWL over time demonstrated non-occlusive properties of emulsions containing silicones, the values of which were comparable to the negative control. Silicone-based emulsions gained higher scores from the volunteers in silkiness, freshness and softness features, while lower scores were obtained in greasiness compared to silicone-free emulsions. No cases of irritation were recorded by the candidates. CONCLUSION: The presence of specific silicones inside a cosmetic product improved its technological characteristics. The rheological identity and the stability feature showed the real suitability of prepared emulsion as a cosmetic product. Moreover, this study demonstrated that silicone-based emulsions are safe for the skin and did not cause skin occlusion. Improved skin sensations are registered by potential consumers when silicones are included in the formulation.


OBJECTIF: De nos jours, l'utilisation de silicones dans la formulation cosmétique reste controversée, étant donné que les ingrédients «naturels¼ ou «biodégradables¼ sont privilégiés. Souvent, l'exclusion et/ou la discrimination de ces excipients du domaine cosmétique ne sont pas motivées, parce que tous les éléments ne peuvent pas être logés à la même enseigne. Par conséquent, nous souhaitons mettre en évidence et souligner les avantages de l'inclusion des silicones dans les émulsions cosmétiques, tout en réfutant et en démystifiant certains mythes liés à leur utilisation. MÉTHODES: Des émulsions sans silicone et des émulsions à base de silicone ont été obtenues dans le cadre d'un processus d'homogénéisation facile. La distribution des tailles de gouttelettes a été évaluée par diffraction laser avec le granulomètre Mastersizer 2000™ et par microscopie optique. Les profils de stabilité à long terme ont été étudiés grâce à l'analyseur optique Turbiscan® Lab Expert. La spectroscopie par diffusion d'ondes (Diffusing Wave Spectroscopy, DWS) par le Rheolaser Master™ et les mesures de balayage de fréquence par le rhéomètre rotatif Kinexus® Pro ont été réalisées pour évaluer une caractérisation rhéologique complète. Des études in vivo ont été menées par le biais de l'évaluation de la perte d'eau transépidermique (PETE) au fil du temps sur des volontaires humains en bonne santé. Une évaluation de la sensation cutanée a été recueillie auprès des mêmes volontaires par le biais d'un questionnaire. RÉSULTATS: L'analyse de la distribution des tailles a révélé une meilleure cohérence des données pour l'émulsion à base de silicone, car la taille des gouttelettes a été maintenue inchangée après 1 mois, ainsi que le paramètre d'uniformité. L'investigation morphologique a confirmé une distribution homogène des gouttelettes pour les deux échantillons. Les silicones ont amélioré la viscosité, la densité et la résistance de la crème, offrant ainsi un profil de stabilité approprié aussi bien à température ambiante qu'après chauffage à 40°C. Le comportement viscoélastique analogue à celui d'un solide a été évalué en présence de contraintes oscillatoires dynamiques. Le suivi de la perte d'eau transépidermique (PETE) au fil du temps a établi des propriétés non occlusives des émulsions contenant des silicones, dont les valeurs étaient comparables à celles du contrôle négatif. Les émulsions à base de silicone ont obtenu des scores plus élevés chez les volontaires en termes de caractéristiques de douceur, de fraîcheur et de souplesse, tandis que des scores plus faibles ont été obtenus en termes d'onctuosité par rapport aux émulsions sans silicone. Aucun cas d'irritation n'a été enregistré chez les candidats. CONCLUSION: La présence de silicones spécifiques dans un produit cosmétique a amélioré ses caractéristiques technologiques. L'identité rhéologique et la caractéristique de stabilité ont montré la pertinence réelle d'une émulsion préparée en tant que produit cosmétique. De plus, cette étude a démontré que les émulsions à base de silicone sont sans danger pour la peau et n'ont provoqué aucune occlusion cutanée. Les consommateurs potentiels enregistrent une amélioration des sensations cutanées lorsque des silicones sont inclus dans la formulation.


Asunto(s)
Cosméticos , Siliconas , Emulsiones/química , Humanos , Reología , Siliconas/química , Piel , Agua/química
19.
Food Res Int ; 158: 111510, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35840219

RESUMEN

Multi-stir bar sorptive extraction (multi-SBSE) represents a viable alternative for recent trends in sample preparation based on a combination of extraction techniques. In this case, increased amount of sorbent and its extended polarity range could advance quality of experimental data obtained in foodomics or metabolomics investigations. With this in mind, it was developed multi-SBSE procedure suitable for authentication of botrytized wine produced in different countries of Tokaj wine region. A design of headspace mode of multi-SBSE was modified to provide additional agitation of a stir bar. An expanded profile of wine samples was obtained with the application of EG-Silicone and PDMS coated stir bars in headspace and direction immersion mode, respectively. Multivariate optimization based on central composite design was selected to determine the influence of various experimental parameters, including extraction temperature enhancing headspace extraction. In our case, proper description of the optimization results required application of a third-order polynomial model, which highlighted dominant influence of salt addition for extraction in both modes. Due to a large number of extracted compounds, comprehensive two-dimensional gas chromatography (GC × GC) was used for assessment of wine samples. Such approach allows reveleaing the presence of sulphur containing compounds, diols, ketone derivatives and methoxybenzenes linking a specific geographical origin. At the same time, the results obtained for compounds common for all the samples were processed with principal component analysis (PCA). Considerable progress for discrimination of the botrytized wines was mainly achieved with combined data from EG-Silicone and PDMS extraction.


Asunto(s)
Vino , Cromatografía de Gases y Espectrometría de Masas/métodos , Siliconas/química , Vino/análisis
20.
Artículo en Inglés | MEDLINE | ID: mdl-35682254

RESUMEN

Hurricane Harvey was associated with flood-related damage to chemical plants and oil refineries, and the flooding of hazardous waste sites, including 13 Superfund sites. As clean-up efforts began, concerns were raised regarding the human health impact of possible increased chemical exposure resulting from the hurricane and subsequent flooding. Personal sampling devices in the form of silicone wristbands were deployed to a longitudinal panel of individuals (n = 99) within 45 days of the hurricane and again one year later in the Houston metropolitan area. Using gas chromatography−mass spectroscopy, each wristband was screened for 1500 chemicals and analyzed for 63 polycyclic aromatic hydrocarbons (PAHs). Chemical exposure levels found on the wristbands were generally higher post-Hurricane Harvey. In the 1500 screen, 188 chemicals were detected, 29 were detected in at least 30% of the study population, and of those, 79% (n = 23) were found in significantly higher concentrations (p < 0.05) post-Hurricane Harvey. Similarly, in PAH analysis, 51 chemicals were detected, 31 were detected in at least 30% of the study population, and 39% (n = 12) were found at statistically higher concentrations (p < 0.05) post-Hurricane Harvey. This study indicates that there were increased levels of chemical exposure after Hurricane Harvey in the Houston metropolitan area.


Asunto(s)
Tormentas Ciclónicas , Hidrocarburos Policíclicos Aromáticos , Inundaciones , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hidrocarburos Policíclicos Aromáticos/análisis , Siliconas/análisis , Siliconas/química
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