Preclinical Trial of Ocotea puberula (Rich.) Nees ("Canela-Guaicá") in Wound Healing: Validation of a Traditional Medicine Practice Used by Indigenous Groups in Southern Brazil.

Background: "Canela-guaicá," "guaicá," or "canela-sebo" [Ocotea puberula (Rich.) Nees] is a native species that is traditionally used by Kaingang indigenous groups for wound healing in southern Brazil. The aim of this study was to extract the mucilage from O. puberula barks, perform its phytochemical and physicochemical characterization, and investigate its healing potential. Methods: A murine wound model was used as a preclinical trial for authentication of the traditional knowledge from Kaingang indigenous communities. Results: Alkaloids and polysaccharides were identified by usual qualitative reactions and Fourier-transform infrared spectroscopy. This natural product showed thermal stability and pseudoplastic properties that were considered suitable for the intended use. A higher initial exacerbation of inflammatory response after 7 days, an improved angiogenesis after 14 days, and an increased wound shrinkage after 21 days were statistically significant for the "canela-guaicá" bark extract in the preclinical trial when compared to the silver calcium alginate dressing (positive control). Conclusion: The healing potential of the "canela-guaicá" bark extract, traditionally used by the Kaingang indigenous community from southern Brazil, was preclinically validated. This study paves the way for designing novel wound dressings containing this natural product in order to treat acute and chronic wounds.

Characterization and In Vitro and In Vivo Evaluation of Tacrolimus-Loaded Poly(ε-Caprolactone) Nanocapsules for the Management of Atopic Dermatitis.

BACKGROUND: Tacrolimus (TAC) is a drug of natural origin used in conventional topical dosage forms to control atopic dermatitis. However, direct application of the drug often causes adverse side effects in some patients. Hence, drug nanoencapsulation could be used as an improved novel therapy to mitigate the adverse effects and enhance bioavailability of the drug. METHODS: Physicochemical properties, in vitro drug release experiments, and in vivo anti-inflammatory activity studies were performed. RESULTS: TAC-loaded nanocapsules were successfully prepared by the interfacial deposition of preformed polymer using poly(ε-caprolactone) (PCL). The nanoparticulate systems presented a spherical shape with a smooth and regular surface, adequate diameter (226 to 250 nm), polydispersity index below 0.3, and suitable electrical stability (-38 to -42 mV). X-ray diffraction confirmed that the encapsulation method provided mainly the drug molecular dispersion in the nanocapsule oily core. Fourier-transform infrared spectra suggested that nanoencapsulation did not result in chemical bonds between drug and polymer. In vitro drug dissolution experiments showed a controlled release with a slight initial burst. The release kinetics showed zero-order kinetics. As per the Korsmeyer-Peppas model, anomalous transport features were observed. TAC-loaded PCL nanocapsules exhibited excellent anti-inflammatory activity when compared to the free drug. CONCLUSIONS: TAC-loaded PCL nanocapsules can be suitably used as a novel nano-based dosage form to control atopic dermatitis.

Effect of Hydroxyapatite Microspheres, Amoxicillin-Hydroxyapatite and Collagen-Hydroxyapatite Composites on Human Dental Pulp-Derived Mesenchymal Stem Cells.

In this study, the preparation and characterization of three hydroxyapatite-based bioactive scaffolds, including hydroxyapatite microspheres (HAps), amoxicillin-hydroxyapatite composite (Amx-HAp), and collagen-hydroxyapatite composite (Col-HAp) were performed. In addition, their behavior in human dental pulp mesenchymal stem cell (hDPSC) culture was investigated. HAps were synthesized through the following methods: microwave hydrothermal, hydrothermal reactor, and precipitation, respectively. hDPSCs were obtained from samples of third molars and characterized by immunophenotypic analysis. Cells were cultured on scaffolds with osteogenic differentiation medium and maintained for 21 days. Cytotoxicity analysis and migration assay of hDPSCs were evaluated. After 21 days of induction, no differences in genes expression were observed. hDPSCs highly expressed the collagen IA and the osteonectin at the mRNA. The cytotoxicity assay using hDPSCs demonstrated that the Col-HAp group presented non-viable cells statistically lower than the control group (p = 0.03). In the migration assay, after 24 h HAps revealed the same migration behavior for hDPSCs observed compared to the positive control. Col-HAp also provided a statistically significant higher migration of hDPSCs than HAps (p = 0.02). Migration results after 48 h for HAps was intermediate from those achieved by the control groups. There was no statistical difference between the positive control and Col-HAp. Specifically, this study demonstrated that hydroxyapatite-based bioactive scaffolds, especially Col-Hap, enhanced the dynamic parameters of cell viability and cell migration capacities for hDPSCs, resulting in suitable adhesion, proliferation, and differentiation of this osteogenic lineage. These data presented are of high clinical importance and hold promise for application in therapeutic areas, because Col-HAp can be used in ridge preservation, minor bone augmentation, and periodontal regeneration. The development of novel hydroxyapatite-based bioactive scaffolds with clinical safety for bone formation from hDPSCs is an important yet challenging task both in biomaterials and cell biology.

Analysis of diagnostic criteria for ventilator-associated pneumonia: a cohort study.

OBJECTIVES: to analyze the diagnostic criteria for ventilator-associated pneumonia recommended by the Brazilian Health Regulatory Agency and the National Healthcare Safety Network/Centers for Disease Control and Prevention, as well as its risk factors. METHODS: retrospective cohort study carried out in an intensive care unit throughout 12 months, in 2017. Analyses included chi-square, simple linear regression, and Kappa statistical tests and were conducted using Stata 12 software. RESULTS: the sample was 543 patients who were in the intensive care unit and under mechanical ventilation, of whom 330 (60.9%) were men and 213 (39.1%) were women. Variables such as gender, age, time under mechanical ventilation, and oral hygiene proved to be significant risk factors for the development of ventilator-associated pneumonia. CONCLUSIONS: patients submitted to mechanical ventilation need to be constantly evaluated so the used diagnostic methods can be accurate and applied in an objective and standardized way in Brazilian hospitals.

Analysis of diagnostic criteria for ventilator-associated pneumonia: a cohort study / Análisis de criterios diagnósticos de neumonía asociada a la ventilación mecánica: estudio de cohorte / Análise dos critérios diagnósticos de pneumonia associada à ventilação mecânica: estudo de coorte

ABSTRACT Objectives: to analyze the diagnostic criteria for ventilator-associated pneumonia recommended by the Brazilian Health Regulatory Agency and the National Healthcare Safety Network/Centers for Disease Control and Prevention, as well as its risk factors. Methods: retrospective cohort study carried out in an intensive care unit throughout 12 months, in 2017. Analyses included chi-square, simple linear regression, and Kappa statistical tests and were conducted using Stata 12 software. Results: the sample was 543 patients who were in the intensive care unit and under mechanical ventilation, of whom 330 (60.9%) were men and 213 (39.1%) were women. Variables such as gender, age, time under mechanical ventilation, and oral hygiene proved to be significant risk factors for the development of ventilator-associated pneumonia. Conclusions: patients submitted to mechanical ventilation need to be constantly evaluated so the used diagnostic methods can be accurate and applied in an objective and standardized way in Brazilian hospitals.

RESUMEN Objetivos: analizar los criterios diagnósticos de neumonía asociada la ventilación mecánica recomendados por la Agencia Nacional de Vigilancia Sanitaria y la National Health Care Safety Network/CDC, así como los factores de riesgo. Métodos: estudio de cohorte retrospectivo realizado en una unidad de terapia intensiva durante 12 meses, en 2017. El análisis se realizó mediante pruebas estadísticas de Chi-cuadrado, regresión lineal simple y test de Kappa, utilizando el programa STATA 12. Resultados: muestra constituida por 543 pacientes hospitalizados en UTI con ventilación mecánica, de ellos 330 (60,9%) eran de sexo masculino, y 213 (39,1%) de sexo femenino. Las variables como sexo, edad, tiempo de ventilación e higiene oral fueron significativas como factores de riesgo para el desarrollo de la NAV. Conclusiones: los pacientes en uso de ventilación mecánica requieren evaluación constante de precisión en los métodos de diagnóstico de manera objetiva y estandarizada en las instituciones hospitalarias brasileñas.

RESUMO Objetivos: analisar os critérios diagnósticos da Pneumonia Associada à Ventilação Mecânica recomendados pela Agência Nacional de Vigilância Sanitária e pela National Healthcare Safety Network/CDC, bem como os fatores de risco. Métodos: estudo de coorte retrospectivo realizado em uma Unidade de Terapia Intensiva, no período de 12 meses, no ano de 2017. A análise foi realizada por meio de testes estatísticos Qui-Quadrado, regressão linear simples e teste de Kappa, pelo programa STATA 12. Resultados: a amostra constitui-se de 543 pacientes hospitalizados na UTI em ventilação mecânica, destes, 330 (60,9%) eram do sexo masculino e 213 (39,1%) eram do sexo feminino. As variáveis, como sexo, idade, tempo de ventilação e higiene oral, foram significativas como fatores de risco para o desenvolvimento da Pneumonia Associada à Ventilação Mecânica (PAV). Conclusões: os pacientes em uso da ventilação mecânica necessitam de constante avaliação para acurácia dos métodos de diagnósticos, de forma objetiva e padronizada, nas instituições hospitalares brasileiras.

Design of Pegylated-Nanocapsules to Diphenyl Diselenide Administration: In Vitro Evidence of Hemocompatible and Selective Antiglioma Formulation.

Diphenyl diselenide [(PhSe)2] is a pleiotropic pharmacological agent, but it has low aqueous solubility. The nanoencapsulation of (PhSe)2 allowed the preparation of an aqueous formulation as well as potentiated its in vitro antitumor effect and the effectiveness in a preclinical model of glioblastoma when administered by the intragastric route. Thus, aiming at maximizing the therapeutic potential of (PhSe)2, the present study designed a pegylated-formulation intending to intravenous administration of the (PhSe)2 as a new approach for glioma therapy. The poly(Ɛ-caprolactone) nanocapsules containing (PhSe)2 were physically coated with polyethyleneglycol (PEG) using the preformed polymer interfacial deposition technique and evaluated through physicochemical, morphological, spectroscopic, and thermal characteristics. Hemocompatibility was determined by the in vitro hemolysis test and cytotoxicity assays were performed in astrocytes and glioma C6 cells (10-100 µM). The pegylated-nanocapsules had an average diameter of 218 ± 25 nm, polydispersity index of 0.164 ± 0.046, zeta potential of - 8.1 ± 1.6 mV, pH 6.0 ± 0.09, (PhSe)2 content of 102.00 ± 3.57%, and encapsulation efficiency around 98%. Besides, the (PhSe)2 pegylated-nanocapsules were spherical, presented absence of chemical interaction among the constituents, and showed higher thermal stability than the non-encapsulated materials. PEG-coated nanocapsules did not cause hemolytic effect while formulations without PEG induced a hemolysis rate above 10%. Moreover, pegylated-nanocapsules had superior in vitro antiglioma effect in comparison to free compound (IC50: 24.10 µM and 74.83 µM, respectively). Therefore, the (PhSe)2-loaded pegylated-nanocapsule suspensions can be considered a hemocompatible formulation for the glioma treatment by the intravenous route.

Ethylcellulose microparticles enhance 3,3'-diindolylmethane anti-hypernociceptive action in an animal model of acute inflammatory pain.

AIM: The present work aimed at the DIM-loaded microparticles development and anti-hypernociceptive action evaluation. METHOD: The formulations were prepared by O/W solvent emulsion-evaporation method and characterised by particle diameter, content and DIM encapsulation efficiency, drug release profile, thermal behaviour and physicochemical state. The anti-hypernociceptive action was evaluated in the animal model of acute inflammatory pain. RESULT: The MPs had a mean diameter in the micrometric range (368 ± 31 µm), narrow size distribution, DIM content of 150 mg/g, encapsulation efficiency around 84% and prolonged compound release. Evaluations of the association form of DIM to MPs demonstrated the feasibility of the systems to incorporate DIM and increases its thermal stability. An improvement in the anti-hypernociceptive action of DIM was observed by its microencapsuation, because it was increased and prolonged. CONCLUSION: Therefore, the MPs developed represent a promising formulation for oral administration of the DIM in the treatment of inflammatory pain.

Co-Loaded Curcumin and Methotrexate Nanocapsules Enhance Cytotoxicity against Non-Small-Cell Lung Cancer Cells.

Background: As part of the efforts to find natural alternatives for cancer treatment and to overcome the barriers of cellular resistance to chemotherapeutic agents, polymeric nanocapsules containing curcumin and/or methotrexate were prepared by an interfacial deposition of preformed polymer method. Methods: Physicochemical properties, drug release experiments and in vitro cytotoxicity of these nanocapsules were performed against the Calu-3 lung cancer cell line. Results: The colloidal suspensions of nanocapsules showed suitable size (287 to 325 nm), negative charge (-33 to -41 mV) and high encapsulation efficiency (82.4 to 99.4%). Spherical particles at nanoscale dimensions were observed by scanning electron microscopy. X-ray diffraction analysis indicated that nanocapsules exhibited a non-crystalline pattern with a remarkable decrease of crystalline peaks of the raw materials. Fourier-transform infrared spectra demonstrated no chemical bond between the drug(s) and polymers. Drug release experiments evidenced a controlled release pattern with no burst effect for nanocapsules containing curcumin and/or methotrexate. The nanoformulation containing curcumin and methotrexate (NCUR/MTX-2) statistically decreased the cell viability of Calu-3. The fluorescence and morphological analyses presented a predominance of early apoptosis and late apoptosis as the main death mechanisms for Calu-3. Conclusions: Curcumin and methotrexate co-loaded nanocapsules can be further used as a novel therapeutic strategy for treating non-small-cell lung cancer.

PEG-PCL Nanocapsules Containing Curcumin: Validation of HPLC Method for Analyzing Drug-loading Efficiency, Stability Testing and Cytotoxicity on NIH-3T3 Cell Line

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.

3,3'-Diindolylmethane nanoencapsulation improves its antinociceptive action: Physicochemical and behavioral studies.

This study aimed to characterize the physicochemical properties of 3,3'-diindolylmethane (DIM)-loaded nanocapsules (NCs) as well as the antinociceptive effect using distinct animal models (hot plate test, formalin-induced nociception and complete Freud's adjuvant induced paw inflammation). The DIM-loaded NCs (composed by primula oil and ethylcellulose) were characterized using differential scanning calorimetry, thermogravimetric analysis, Fourier-transformed infrared spectroscopy, X-ray diffractometry and scanning electron microscopy. The physicochemical characterization demonstrated that DIM could be molecularly dispersed into the NCs, whose size was nanometric with a spherical shape. An improvement in DIM thermal stability was achieved by its encapsulation and there were no interactions among the formula components. For the nociceptive evaluation, male adult Swiss mice were pretreated with the NCs or free DIM by the intragastric route at the dose of 10 mg/Kg (time-response curve), 5 or 2.5 mg/Kg (dose-response curve). The behavioral tests were performed over an experimental period of 0.5-8 h. Both free and nanoencapsulated DIM reduced the mechanical hypernociception induced by CFA, mitigated nociceptive behavior of formalin-induced neurogenic and inflammatory pain and increased paw withdrawal latency assessed by the hot-plate test. Importantly, the DIM nanoencapsulation promoted a rapid initiation and prolonged the bioactive antinociceptive action (up to 8 h) as well as reduced the effective dose in comparison to its free form. In summary, this study reported that the NCs had adequate nanometric size, increased DIM stability and its antinociceptive action in different animal models, suggesting that the formulation may be a possible therapeutic alternative to the management of pain and inflammatory-related pathologies.

Adapalene-loaded poly(ε-caprolactone) microparticles: Physicochemical characterization and in vitro penetration by photoacoustic spectroscopy.

Adapalene (ADAP) is an important drug widely used in the topical treatment of acne. It is a third-generation retinoid and provides keratolytic, anti-inflammatory, and antiseborrhoic action. However, some topical adverse effects such as erythema, dryness, and scaling have been reported with its commercial formula. In this sense, the microencapsulation of this drug using polyesters can circumvent its topical side effects and can lead to the enhancement of drug delivery into sebaceous glands. The goal of this work was to obtain ADAP-loaded poly(ε-caprolactone) (PCL) microparticles prepared by a simple emulsion/solvent evaporation method. Formulations containing 10 and 20% of ADAP were successfully obtained and characterized by morphological, spectroscopic, and thermal studies. Microparticles presented encapsulation efficiency of ADAP above 98% and showed a smooth surface and spherical shape. Fourier transform infrared spectroscopy (FTIR) results presented no drug-polymer chemical bond, and a differential scanning calorimetry (DSC) technique showed a partial amorphization of the drug. ADAP permeation in the Strat-M membrane for transdermal diffusion testing was evaluated by photoacoustic spectroscopy (PAS) in the spectral region between 225 and 400 nm after 15 min and 3 h from the application of ADAP-loaded PCL formulations. PAS was successfully used for investigating the penetration of polymeric microparticles. In addition, microencapsulation decreased the in vitro transmembrane diffusion of ADAP.

Long-lasting anti-platelet activity of cilostazol from poly(ε-caprolactone)-poly(ethylene glycol) blend nanocapsules.

Cilostazol (CLZ) acts as a vasodilator and antiplatelet agent and is the main drug for the treatment of intermittent claudication (IC) related to peripheral arterial disease (PAD). The usual oral dose is 100 mg twice a day, which represents a disadvantage in treatment compliance. CLZ presents several side effects, such as headache, runny nose, and dizziness. This paper aimed to obtain novel polymeric nanocapsules prepared from poly(ε-caprolactone)-poly(ethylene glycol) (PCL-PEG) blend containing CLZ. Nanocapsules showed pH values between 6.1 and 6.3, average size lower than 137 nm, low polydispersity index (<0.22) and negative zeta potential. These nanoformulations demonstrated spherical shape with smooth surface. Results achieved by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) indicated drug amorphization compared to pure CLZ. Fourier-transformed infrared spectroscopy (FTIR) showed no chemical bonds between drug and polymers. Formulations presented suitable stability for physical parameters. The in vitro drug release demonstrated prolonged release with no burst effect. Drug release was controlled by both mechanisms of polymer relaxation/degradation and Fickian diffusion. Moreover, chosen CLZ-loaded nanocapsules provided an in vivo prolonged antiplatelet effect for CLZ statistically similar to aspirin. These formulations can be further used as a feasible oral drug delivery carrier for controlled release of CLZ in order to treat PAD and IC events.

Nanocapsules improve indole-3-carbinol photostability and prolong its antinociceptive action in acute pain animal models.

This study aimed the development of nanocapsules (NCs) for oral indole-3-carbinol (I3C) administration and evaluation of antinociceptive potential of this compound in its two forms, free and nanoencapsulated, using acute pain models. NCs showed adequate physicochemical characteristics and protected the I3C against UVC radiation exposure. It was observed no chemical bond between I3C and polymer by FTIR. Besides, X-ray and DSC analysis suggested that I3C was molecularly dispersed in NCs. The dialysis bag technique showed that almost 100% of the compound was released from NCs at 360min. Mathematical modeling demonstrated that this release occurred in two rates, with an initial burst effect followed by a slower release of I3C. Regarding the in vivo analysis, time-response curve showed that both forms of I3C caused an inhibition in inflammatory phase of nociception induced by formalin and increased the latency response in hot plate test. Interestingly, NCs were able to prolong the I3C effect in both tests. Furthermore, in dose-response curve, only I3C in its nanoencapsulated form presented effect on inflammatory phase of the formalin test. In conclusion, NCs to I3C incorporation presented adequate nanometric characteristics and prolonged its antinociceptive action in acute pain models tested.

p,p'-Methoxyl-diphenyl diselenideincorporation into polymeric nanocapsules improves its antinociceptive action: Physicochemical and behavioral studies.

The p,p'-methoxyl-diphenyl diselenide [(OMePhSe)2] is an, organoselenium compound that elicits antinociceptive action in different, animal models of pain. However, the compound has physicochemical, Limitations that delay its clinical studies. Herein, (OMePhSe)2, nanocapsules were developed and their physicochemical properties were, analyzed using different techniques (Scanning electron microscopy with, field emissionguns, wide-angle X-ray diffractometry, fourier-transform, infrared spectroscopy, thermogravimetric analysis and differential, scanning calorimetry). The antinociceptive action of (OMePhSe)2 free or, nanoencapsulated was evaluated in an animal model of thermal nociception., The (OMePhSe)2 nanocapsules or the free compound (25mg/kg, 10ml/kg), were administered to Swiss mice by the intragastric (i.g.), intraperitoneal (i.p.) or subcutaneous (s.c.) route in a single or, repeated administration regimen. The (OMePhSe)2 nanocapsules had, spherical shape, no chemical interaction among the formulation components, and high thermal stability. Treatment with (OMePhSe)2 elicited an, antinociceptive action independent of the administration route and, regimen schedule. The (OMePhSe)2 incorporation into nanocapsules, prolonged and improved the compound antinociceptive action. The, (OMePhSe)2 antinociceptive action was influenced by the route of, administration (intragastric>intraperitoneal>subcutaneous) and by the, vehicle used (NCs>canola oil). Altogether, the current study, demonstrated that the (OMePhSe)2 nanoencapsulation increased the compound, thermal stability and the antinociceptive action in mice, suggesting that, the polymeric nanocapsules provided advantages in comparison to the free, compound form.

Miconazole Nitrate-loaded Microparticles For Buccal Use: Immediate Drug Release and Antifungal Effect.

BACKGROUND: Miconazole nitrate has been widely employed in treatment of oral mycoses, however your immediate bio-availability and location in the affected area is critical. OBJECTIVE: The aim of this study was to prepare and evaluate Eudragit® L100 and Gantrez MS-955 microparticles containing miconazole nitrate for oral delivery. METHODS: Microparticles were prepared by spray-drying method to achieve high encapsulation efficiency and increase the drug solubility. The microparticles were formed containing 10% and 20% of drug on polymer Eudragit® L100 (E10 and E20), Gantrez MS-955 (G10 and G20) or their combination (EG10 and EG20). The influence of formulation factors (polymer:drug ratio, type of polymer) on yield percent, encapsulation efficiency, particle size, Fourier-transformed infrared spectroscopy (FTIR), X-ray diffraction, differential scanning calorimetry, in vitro drug release and antifungal activity were investigated. RESULTS: Acceptable yield, micrometer-sized and drug-loading efficiencies higher than 89% were obtained. No change in FTIR assignments was recorded after the microencapsulation procedure. X-ray and differential scanning calorimetry studies revealed amorphous/non-crystalline formulations. Miconazole nitrate-microparticles provided a remarkable increase of dissolution rate of the drug. Miconazole nitrate and G10, G20 and EG20 microparticles fitted to biexponential kinetic model, and E10, E20 and EG10 microparticles, monoexponential kinetic model. The antifungal activity test demonstrated that miconazole nitrate-microparticles possessed the same anti-Candida albicans activity as the pure drug. CONCLUSION: These results indicate that miconazole nitrate-microparticles are feasible carriers for increased release of miconazole at oral environment.

Development and characterization of hyaluronic acid-lysine nanoparticles with potential as innovative dermal filling

ABSTRACT Skin aging causes changes such as wrinkles and flaccidity leading to a large demand for aesthetic procedures, including dermal filling. A key agent in dermal filling is hyaluronic acid (HA), which is a naturally occurring glycosaminoglycan. However, it is a hydrophilic macromolecule that experiences great difficulty in crossing the skin barrier causing most commercial formulations containing it to be injectable, which in turn brings risks since they involve an invasive technique. In that sense, the aim of this study was to develop and characterize nanoparticles obtained from ionic interaction between HA and lysine (Lys) for use as a potential agent of dermal filling for topical application, increasing and improving its applicability and safety. To this end, nanoparticles were obtained by dripping of Lys over HA under magnetic stirring. A nanometric size was confirmed and a suitable surface charge was obtained by zeta potential. Nanoparticles were almost spherical in shape with a smooth surface. Interaction between raw materials for preparing nanoparticles was studied by FTIR and NMR spectroscopy and an ionic interaction was confirmed. These physicochemical features suggest that obtained nanoparticles can be further used as a topical dermal filling.

Spray-dried solid dispersions containing ferulic acid: comparative analysis of three carriers, in vitro dissolution, antioxidant potential and in vivo anti-platelet effect.

This article aimed to improve the relative solubility and dissolution rate of ferulic acid (FA) by the use of spray-dried solid dispersions (SDs) in order to ensure its in vitro antioxidant potential and to enhance its in vivo anti-platelet effect. These SDs were prepared by spray-drying at 10 and 20% of drug concentration using polyvinylpyrrolidone K30 (PVP-K30), polyethylene glycol 6000 (PEG 6000) and poloxamer-188 (PLX-188) as carriers. SDs and physical mixtures (PM) were characterized by SEM, XRPD, FTIR spectroscopy and TGA analysis. Spray-dried SDs containing FA were successfully obtained. Relative solubility of FA was improved with increasing carrier concentration. PVP-K30 and PEG 6000 formulations showed suitable drug content values close to 100%, whereas PLX-188 presented mean values between 70 and 90%. Agglomerates were observed depending on the carrier used. XRPD patterns and thermograms indicated that spray-drying led to drug amorphization and provided appropriate thermal stability, respectively. FTIR spectra demonstrated no remarkable interaction between carrier and drug for PEG 6000 and PLX-188 SDs. PVP-K30 formulations had changes in FTIR spectra, which denoted intermolecular O-H•••O = C bonds. Spray-dried SDs played an important role in enhancing dissolution rate of FA when compared to pure drug. The free radical-scavenging assay confirmed that the antioxidant activity of PEG 6000 10% SDs was kept. This formulation also provided a statistically increased in vivo anti-platelet effect compared to pure drug. In summary, these formulations enhanced relative solubility and dissolution rate of FA and chosen formulation demonstrated suitable in vitro antioxidant activity and improved in vivo anti-platelet effect.

Spray-dried Eudragit® L100 microparticles containing ferulic acid: Formulation, in vitro cytoprotection and in vivo anti-platelet effect.

This paper aimed to obtain new spray-dried microparticles containing ferulic acid (FA) prepared by using a methacrylic polymer (Eudragit® L100). Microparticles were intended for oral use in order to provide a controlled release, and improved in vitro and in vivo biological effects. FA-loaded Eudragit® L100 microparticles were obtained by spray-drying. Physicochemical properties, in vitro cell-based effects, and in vivo platelet aggregation were investigated. FA-loaded Eudragit® L100 microparticles were successfully prepared by spray-drying. Formulations showed suitable encapsulation efficiency, i.e. close to 100%. Microparticles were of spherical and almost-spherical shape with a smooth surface and a mean diameter between 2 and 3µm. Fourier-transformed infrared spectra demonstrated no chemical bond between FA and polymer. X-ray diffraction and differential scanning calorimetry analyses indicated that microencapsulation led to drug amorphization. FA-loaded microparticles showed a slower dissolution rate than pure drug. The chosen formulation demonstrated higher in vitro cytoprotection, anti-inflammatory and immunomodulatory potential and also improved in vivo anti-platelet effect. These results support an experimental basis for the use of FA spray-dried microparticles as a feasible oral drug delivery carrier for the controlled release of FA and improved cytoprotective and anti-platelet effects.

A Stability-Indicating HPLC-DAD Method for Determination of Ferulic Acid into Microparticles: Development, Validation, Forced Degradation, and Encapsulation Efficiency.

A simple stability-indicating HPLC-DAD method was validated for the determination of ferulic acid (FA) in polymeric microparticles. Chromatographic conditions consisted of a RP C18 column (250 mm × 4.60 mm, 5 µm, 110 Å) using a mixture of methanol and water pH 3.0 (48 : 52 v/v) as mobile phase at a flow rate of 1.0 mL/min with UV detection at 320 nm. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of quantification, limit of detection, accuracy, precision, and robustness provided suitable results regarding all parameters investigated. The calibration curve was linear in the concentration range of 10.0-70.0 µg/mL with a correlation coefficient >0.999. Precision (intraday and interday) was demonstrated by a relative standard deviation lower than 2.0%. Accuracy was assessed by the recovery test of FA from polymeric microparticles (99.02% to 100.73%). Specificity showed no interference from the components of polymeric microparticles or from the degradation products derived from acidic, basic, and photolytic conditions. In conclusion, the method is suitable to be applied to assay FA as bulk drug and into polymeric microparticles and can be used for studying its stability and degradation kinetics.