Brain and visceral gene editing of mucopolysaccharidosis I mice by nasal delivery of the CRISPR/Cas9 system.

BACKGROUND: Mucopolysaccharidosis type I (MPS I) is an inherited disease caused by deficiency of the enzyme alpha-l-iduronidase (IDUA). MPS I affects several tissues, including the brain, leading to cognitive impairment in the severe form of the disease. Currently available treatments do not reach the brain. Therefore, in this study, we performed nasal administration (NA) of liposomal complexes carrying two plasmids encoding for the CRISPR/Cas9 system and for the IDUA gene targeting the ROSA26 locus, aiming at brain delivery in MPS I mice. METHODS: Liposomes were prepared by microfluidization, and the plasmids were complexed to the formulations by adsorption. Physicochemical characterization of the formulations and complexes, in vitro permeation, and mucoadhesion in porcine nasal mucosa (PNM) were assessed. We performed NA repeatedly for 30 days in young MPS I mice, which were euthanized at 6 months of age after performing behavioral tasks, and biochemical and molecular aspects were evaluated. RESULTS: Monodisperse mucoadhesive complexes around 110 nm, which are able to efficiently permeate the PNM. In animals, the treatment led to a modest increase in IDUA activity in the lung, heart, and brain areas, with reduction of glycosaminoglycan (GAG) levels in serum, urine, tissues, and brain cortex. Furthermore, treated mice showed improvement in behavioral tests, suggesting prevention of the cognitive damage. CONCLUSION: Nonviral gene editing performed through nasal route represents a potential therapeutic alternative for the somatic and neurologic symptoms of MPS I and possibly for other neurological disorders.

Development and characterization of CD73-siRNA-loaded nanoemulsion: effect on C6 glioma cells and primary astrocytes.

Introduction: Glioblastoma (GB) is the most common malignant brain tumor and is characterized by high invasiveness, poor prognosis, and limited therapeutic options. Silencing gene expression, through the use of small interfering RNA (siRNA), has been proposed as an alternative to conventional cancer therapy. Here, we evaluated the potential of CD73 as a new therapeutic target, since it is overexpressed in solid tumors and has emerged as a promising target to control GB progression.Methods: A cationic nanoemulsion (NE) as an intravenous siRNA-CD73 delivery system was developed and its effect on C6 glioma cell viability was determined.Results: The nanostructured system was effective in complexing oligonucleotides for delivery to target cells. In addition, we observed that the NE-siRNA-CD73 complex was effective in reducing CD73 protein levels and AMPase activity, which were related to decreased C6 glioma cell viability.Conclusions: These findings indicate the potential of siRNA-CD73-loaded cationic NE as a therapeutic alternative for glioma treatment.

HPLC-UV method for temozolomide determination in complex biological matrices: Application for in vitro, ex vivo and in vivo studies.

A high-performance liquid chromatography method for temozolomide (TMZ) determination in complex biological matrices was developed and validated for application in in vitro, ex vivo and in vivo studies of new nanotechnology-based systems for TMZ nasal delivery. The method was able to quantify TMZ in nanoemulsions, following cellular uptake, in the porcine nasal mucosa and in mouse plasma and brain. Analyses were performed on a C18 column at 35°C, under UV detection at 330 nm. The mobile phase was methanol-acetic acid 0.5% (30:70, v/v), eluted at an isocratic flow rate of 1.1 mL/min. The method was found to be specific, precise, accurate, robust and linear (0.05 to 5 µg/mL) for TMZ determination in all matrices. No interference of TMZ degradation products was found under various stress conditions such as acidic, alkaline, oxidative, light and thermal exposure, demonstrating stability. The method was applied for the quantification of TMZ in different matrices, i.e. the efficiency of nanoemulsions in vitro in increasing TMZ cellular uptake, ex vivo TMZ permeation and retention in the porcine nasal mucosa tissue, and for in vivo TMZ quantification in mouse brain following intranasal nanoemulsion administration compared with free TMZ.

Essential Oils and Isolated Terpenes in Nanosystems Designed for Topical Administration: A Review.

Essential oils are natural products with a complex composition. Terpenes are the most common class of chemical compounds present in essential oils. Terpenes and the essential oils containing them are widely used and investigated by their pharmacological properties and permeation-enhancing ability. However, many terpenes and essential oils are sensitive to environmental conditions, undergoing volatilization and chemical degradation. In order to overcome the chemical instability of some isolated terpenes and essential oils, the encapsulation of these compounds in nanostructured systems (polymeric, lipidic, or molecular complexes) has been employed. In addition, nanoencapsulation can be of interest for pharmaceutical applications due to its capacity to improve the bioavailability and allow the controlled release of drugs. Topical drug administration is a convenient and non-invasive administration route for both local and systemic drug delivery. The present review focuses on describing the current status of research concerning nanostructured delivery systems containing isolated terpenes and/or essential oils designed for topical administration and on discussing the use of terpenes and essential oils either for their biological activities or as permeation enhancers in pharmaceutic formulations.

Quercetin and 3-O-methylquercetin in vitro skin layers permeation/retention from hydrogels: why only a methoxy group difference determines different behaviors?

OBJECTIVES: The present study was designed to verify if quercetin (QCT), a flavonoid with antioxidant and antiviral activity, and 3-O-methylquercetin (3OMQ), a quercetin C3-methoxylated derivative, present differences in their behavior against complexation with ß-cyclodextrin (ß-CD) and the corresponding permeation/retention trhough porcine ear skin, when incorporated into hydroxypropyl methylcellulose (HPMC) or chitosan (CS) hydrogels. METHODS: The influence of ß-CD on the skin permeation/retention of QCT and 3OMQ from hydrogels is comparatively evaluated for both flavonoids using porcine ear skin in Franz cells model. The properties of the two flavonoids using the semi-empirical method Recife Model was studied. KEY FINDINGS: Quercetin presented higher skin retention compared with its C3-methoxy derivative 3OMQ. The best permeation/retention of QCT was observed when it was incorporated into CS hydrogel containing 5% ß-CD, whereas, for 3OMQ, the HPMC hydrogel containing 5% ß-CD was the best formulation. The flavonoids complexation with ß-CD in water occurred preferentially with the insertion of the B ring through the secondary OH rim. CONCLUSIONS: The dynamic molecular modeling revealed that the methyl group at C3 in 3OMQ molecule determined significant difference in its complexation with ß-CD, in comparison to its analogous QCT and that difference is coincident with the permeation behavior of these flavonoids, denoting a possible relationship with their molecular dynamics.

Intestinal permeability enhancement of benzopyran HP1-loaded nanoemulsions.

The benzopyran HP1, a compound isolated from Hypericum polyanthemum, has demonstrated significant opioid-mediated antinociceptive activity after its oral administration. Despite the pharmacological potential, the poor aqueous solubility limits the oral absorption of this compound. For this reason, HP1 has been alternatively incorporated in lipid-based drug delivery systems. Given that nanoemulsions showed higher antinociceptive action than the free compound in a previous report, in this study, the main objective was to investigate the intestinal transport mechanisms of this system. The Ussing chamber model and rat jejunum were selected for this purpose. The apparent permeability coefficient of HP1 increased approximately 5.3 times after its incorporation in nanoemulsions. Considering that the absorptive transport of HP1 was significantly higher than the secretory transport, the participation of active transporters was suggested. The amount of HP1 in the acceptor chamber was reduced during permeability assays performed at 4 °C, supporting the hypothesis that active transporters are involved in the intestinal transport of this compound. The amount of free fatty acids released from nanoemulsion was approximately 60% after 90 min, demonstrating that part of this system is disassembled before absorption. Nanoemulsion constituents would be able to form new structures with biological constituents, leading to a rapid solubilization of HP1. A mucoadhesion rate of 50% was achieved by nanoemulsion after 30 min, which would also contribute to explain the higher absorption of this system. The particle size of the nanoemulsion is also compatible with endocytosis-mediated transport. Taken together, these results suggest that nanoemulsions containing HP1 could be efficiently delivered to humans considering that different absorption mechanisms are exploited.

Box Behnken design of siRNA-loaded liposomes for the treatment of a murine model of ocular keratitis caused by Acanthamoeba.

Acanthamoeba keratitis is an ophthalmic disease with no specific treatment that specially affects contact lens users. The silencing of serine phosphatase (SP) and glycogen phosphorylase (GP) proteins produced by Acanthamoeba has been shown to significantly reduce the cytopathic effect, although no vehicle was proposed yet to deliver the siRNA sequences to the trophozoites. In this study, PEGylated cationic liposomes were proposed and optimized using Box-Behnken design. The influence of DOTAP:DOPE ratio, DSPE-PEG concentration, and siRNA/DOTAP charge ratio were evaluated over both biological response and physicochemical properties of liposomes. The ratio of DOTAP:DOPE had an effect in the trophozoite activity whereas the charge ratio influenced both size and protease activity. The predicted values were very close to the observed values, yielding a formulation with good activity and toxicity profile, which was used in the following experiments. A murine model of ocular keratitis was treated with siGP + siSP-loaded liposomes, as well as their respective controls, and combined treatment of liposomes and chlorhexidine. After 15 days of eight daily administrations, the liposomal complex combined with chlorhexidine was the only treatment able to reverse the more severe lesions associated with keratitis. There was 60% complete regression in corneal damage, with histological sections demonstrating the presence of an integral epithelium, without lymphocytic infiltrate. The set of results demonstrate the efficacy of a combined therapy based on siRNA with classical drugs for a better prognosis of keratitis caused by Acanthamoeba.

Physicochemical properties of cationic nanoemulsions and liposomes obtained by microfluidization complexed with a single plasmid or along with an oligonucleotide: Implications for CRISPR/Cas technology.

In this study, we investigated the effects of the association of a single plasmid or its co-complexation along with an oligonucleotide on the physicochemical properties of cationic nanoemulsions and liposomes intended for gene editing. Formulations composed of DOPE, DOTAP, DSPE-PEG (liposomes), MCT (nanoemulsions), and water were obtained by microfluidization. DSPE-PEG was found to play a crucial role on the size and polydispersity index of nanocarriers. Nucleic acids were complexated by adsorption at different charge ratios. No significant differences were noticed in the physicochemical properties of nanocarriers (i.e. droplet size, polydispersity index, or zeta potential) when a single plasmid or both plasmid and oligonucleotide were adsorbed to the formulations. Transmission electron microscopy photomicrographs suggested round nanostructures with the nucleic acids and DSPE-PEG enfolding the surface. Complexes at +4/-1 charge ratio protected nucleic acids against DNase I degradation. The oligonucleotide seemed to be released from the liposomal complexes, while nanoemulsions only released the plasmid after 24 and 48 h of incubation in DMEM supplemented or not. In vitro experiments demonstrated that complexes were highly tolerable to human fibroblasts, Hep-G2, and HEK-293 cells, demonstrating also an uptake ability of about 30%, 30%, and 90%, respectively, no matter what the formulation or the combination of nucleic acids used. Transfection efficiency of the formulations was around 25% in human fibroblasts, 32% in HEK-293, and 15% in Hep-G2 cells. The overall results demonstrated the behavior of liposomes and nanoemulsions complexed with a plasmid or a mixture of a plasmid and an oligonucleotide, and demonstrated that the association with one or two nucleic acids sequences of different length does not seem to interfere in the physicochemical characteristics of complexes or in the uptake capacity by three different types of cells.

Optimization, validation and application of headspace solid-phase microextraction gas chromatography for the determination of 1-nitro-2-phenylethane and methyleugenol from Aniba canelilla (H.B.K.) Mez essential oil in skin permeation samples.

Aniba canelilla (H.B.K.) Mez is an aromatic plant from the Amazon region whose essential oil has 1-nitro-2-phenylethane (NP) and methyleugenol (ME) as major compounds. Despite of the scientifically proven antifungal and anti-inflammatory activities for these compounds, there is no report up to date about the topical permeation or quantification of NP and ME on skin samples. The aim of this study was the validation of an optimized bioanalytical method by solid-phase microextraction in headspace mode in gas chromatograph with flame ionization detector (HS-SPME-GC-FID) for the determination of NP and ME from the oil in different samples from permeation study, such as porcine ear skin (PES) layers (stratum corneum, epidermis and dermis) and receptor fluid (RF). For this propose polydimethylsiloxane fibers (100 µm) were used and HS-SPME extraction condition consisted of 53 °C, 21 min, and 5% w.v-1 NaCl addition. The wide range of the calibration curve (2.08-207.87 µg mL-1 for NP and 0.40-40.41 µg mL-1 for ME), the presence of matrix interferences and the intrinsic characteristics of HS-SPME required a data linearization using Log10. Thereby, data and the gained results presented homoscedasticity, normalization of residues and adequate linearity (r2 > 0.99) and accuracy for both compounds. In order to verify the applicability of the validated method, the HS-SPME-GC-FID procedure was performed to determine the amount of NP and ME permeated and retained in samples after Franz diffusion cell study from different dosages (20, 100 and 200 µL) of A. canelilla oil. Compounds permeation showed a progressive increase and penetration dependence based on the dosage applied. Furthermore, retention was in order receptor fluid >> dermis >> epidermis >> stratum corneum for both compounds, suggesting NP and ME could penetrate deep tissue, probably due to the partition coefficient, mass, size, and solubility of these compounds. In conclusion, the proposed method by HS-SPME-GC-FID to quantify 1-nitro-2-phenylethane and methyleugenol from Aniba canelilla essential oil was able to determine selectively, precisely and accurately these main compounds in skin permeation samples.

Coumestrol/hydroxypropyl-ß-cyclodextrin association incorporated in hydroxypropyl methylcellulose hydrogel exhibits wound healing effect: in vitro and in vivo study.

Several beneficial effects on the skin have been reported for coumestrol (COU), such as protection against photoaging and improvement of skin elasticity and thickness in postmenopausal women. However no reports on the effect of COU on wound healing were found. Nevertheless, COU has low aqueous solubility, which is a crucial limitation for biological tests. The present study was designed as a two-step experiment to evaluate the wound healing effect of COU. First, we used fibroblasts and the experimental in vitro artificial wound model, scratch assay, to compare the effects of COU free, dissolved in dimethyl sulfoxide (DMSO) or Dulbecco's modified Eagle's medium (DMEM), or associated with hydroxypropyl-ß-cyclodextrin (HPßCD). The 50 µM (66.1%) and 10 µM (56.3%) COU/HPßCD association induced cell proliferation and migration in inflicted wounds. Subsequently, the in vivo wound healing experimental model (Wistar rats) revealed that COU/HPßCD incorporated into hypromellose (HPMC) hydrogel had similar efficacy in wound healing in comparison to the positive control (Dersani®), with the advantage that 50% wound healing was achieved within a shorter period. In summary, the results successfully demonstrated, for the first time, the wound healing effect of COU/HPßCD incorporated into HPMC hydrogel and describe the feasibility of the biological tests with the use of HPßCD instead DMSO.

A novel, simplified and stability-indicating high-throughput ultra-fast liquid chromatography method for the determination of rosmarinic acid in nanoemulsions, porcine skin and nasal mucosa.

Currently, there is an increasing interest on the development of topical formulations containing rosmarinic acid (RA) due to its well-documented antioxidant activity. This study aimed to develop and validate a stability-indicating ultra-fast liquid chromatography (UFLC) method for the determination of RA in nanoemulsions, porcine skin and nasal mucosa intended to be applied in permeation/retention studies and for development of topical nanoemulsions. Chromatographic separation was carried out using a C18 column packed with 2.6 µm particle size in isocratic conditions using as mobile phase water:acetonitrile (83:17, v/v), acidified with 0.1% trifluoracetic acid (v/v), with a total time of analysis of 3.5 min and detection at 330 nm. RA analysis was specific in the presence of both non-biological (blank nanoemulsion and receptor fluid) and biological matrices (porcine ear skin and porcine nasal mucosa). No interference of degradation products of RA was verified after different stress conditions such as acidic, alkaline, oxidative, light exposure (UV-A and UV-C) and thermal demonstrating the method stability-indicating property. The analytical (0.1-10.0 µg·mL-1) and bioanalytical (0.5-10.0 µg·mL-1) linearity was proved by analysis of the calibration curves of RA and no matrix effect was observed. The method was sensitive, precise and accurate, and showed recovery higher than 85%. The method was considered robust as evaluated by a Plackett-Burman experimental design. In the validated conditions, the RA was determined in the nanoemulsions obtained by spontaneous emulsification procedure (1.007 ±â€¯0.040 mg·mL-1), porcine ear skin (1.13 ±â€¯0.19 µg·cm-2) and nasal mucosa (22.46 ±â€¯3.99 µg·cm-2) after retention/permeation studies. Thus, a highly sensitive, simple, fast and stability-indicating method was developed for RA analysis during the development of topical nanoemulsions and bioanalytical assays in complex matrices.

Anti-inflammatory Effect from a Hydrogel Containing Nanoemulsified Copaiba oil (Copaifera multijuga Hayne).

Copaiba oil is used as a popular medicine in the Amazonian forest region, especially due to its anti-inflammatory properties. In this paper, we describe the formulation of hydrogel containing copaiba oil nanoemulsions (with positive and negative charges), its skin permeation, and its anti-inflammatory activity in two in vivo models: mouse ear edema and rat paw edema. Three hydrogels were tested (Carbopol®, hydroxyethylcellulose and chitosan), but only Carbopol® and hydroxyethylcellulose hydrogels presented good stability and did not interfere with the nanoemulsions droplet size and polydispersity index. In skin permeation assay, both formulations, positively charged nanoemulsion (PCN) and negatively charged nanoemulsion (NCN), presented a high retention in epidermis (9.76 ± 2.65 µg/g and 7.91 ± 2.46 µg/cm2, respectively) followed by a smaller retention in the dermis (2.43 ± 0.91 and 1.95 ± 0.56 µg/cm2, respectively). They also presented permeation to the receptor fluid (0.67 ± 0.22 and 1.80 ± 0.85 µg/cm2, respectively). In addition, anti-inflammatory effect was observed to NCN and PCN with edema inhibitions of 69 and 67% in mouse ear edema and 32 and 72% in rat paw edema, respectively. Histological cuts showed the decrease of inflammatory factors, such as dermis and epidermis hyperplasia and inflammatory cells infiltration, confirming the anti-inflammatory effect from both copaiba oil nanoemulsions incorporated in hydrogel.

siRNA-loaded liposomes: Inhibition of encystment of Acanthamoeba and toxicity on the eye surface.

Current treatments for Acanthamoeba keratitis are unspecific. Because of the presence of the resilient cyst form of the parasite, the infection is persistent. Silencing the key protein of cyst formation, glycogen phosphorylase, has shown potential for reducing encystment processes of the Acanthamoeba trophozoite. However, a suitable carrier to protect and deliver siRNA sequences is still needed. DOTAP: DOPE:DSPE-PEG liposomes were prepared by three different techniques and used to associate a therapeutic siRNA sequence. Liposomes prepared by film hydration followed by membrane extrusion were considered the most adequate ones with average size of 250 nm and zeta potential of +45 mV, being able to associate siRNA for at least 24 hr in culture medium. siRNA-liposomes could inhibit up to 66% of the encystment process. Cell viability studies demonstrated MTT reduction capacity higher than 80% after 3 hr incubation with this formulation. After 24 hr of incubation, LDH activity ranged for both the formulations from around 4% to 40%. In vivo tolerance studies in mice showed no macroscopic alteration in the eye structures up to 24 hr after eight administrations during 1 day. Histological studies showed regular tissue architecture without any morphological alteration. Overall, these results suggest that the formulations developed are a promising new strategy for the treatment of ocular keratitis caused by Acanthamoeba spp.

Trypanocidal activity of the compounds present in Aniba canelilla oil against Trypanosoma evansi and its effects on viability of lymphocytes.

Aniba canelilla (H.B.K.) Mez, popularly known as "casca-preciosa" (precious bark), is a plant of the Lauraceae family, widely distributed in the Amazon region. Its major constituent is 1-nitro-2-phenylethane, a rare molecule in plants which is responsible for this plant's cinnamon scent. The present study aimed to report the chemical characterization of the oil extracted from Aniba canelilla using gas-chromatography/mass spectrometry and to assess its in vitro trypanocidal activity against Trypanosoma evansi, a prevalent haemoflagellate parasite that affects a broad range of mammal species in Africa, Asia and South America. The oil presented 1-nitro-2-phenylethane (83.68%) and methyleugenol (14.83%) as the two major components. The essential oil as well as both major compounds were shown to exert trypanocidal effect. Methyleugenol was slightly more active than 1-nitro-2-phenylethane. In vitro studies showed that the oil extracted from the stems of A. canelilla may be regarded as a potential natural treatment for trypanosomosis, once proven their in vivo action, may be an interesting alternative in the treatment of infected animals with T. evansi.

Determination of the main impurities formed after acid hydrolysis of soybean extracts and the in vitro mutagenicity and genotoxicity studies of 5-ethoxymethyl-2-furfural.

Soybean acid hydrolyzed extracts are raw-materials widely used for manufacturing of pharmaceuticals and cosmetics products due to their high content of isoflavone aglycones. In the present study, the main sugar degradation products 5-hydroxymethyl-2-furfural (HMF) and 5-ethoxymethyl-2-furfural (EMF) were quantitatively determined after acid hydrolysis of extracts from different soybean cultivars by a validated liquid chromatography method. The furanic compounds determined in samples cover the range of 0.16-0.21mg/mL and 0.22-0.33mg/mL for HMF and EMF, respectively. Complementarily, due to the scarce literature regarding the EMF toxicology, this study also assessed the EMF mutagenicity by the Salmonella/microsome test and genotoxicity by the comet assay. The results revealed that EMF did not show mutagenicity at the range of 50-5000µg/plate in S. typhimurium strains TA98, TA97a, TA100, TA102 and TA1535, but induced DNA damage in HepG2 cells at non-cytotoxic doses of 0.1-1.3mg/mL, mainly by oxidative stress mechanisms. Based on literature of HMF genotoxicity, and considering the EMF genotoxicity results herein shown, purification procedures to remove these impurities from extracts are recommended during healthcare products development to ensure the security of the products.

Nanotechnology applied to treatment of mucopolysaccharidoses.

INTRODUCTION: Mucopolysaccharidoses (MPS) are genetic disorders caused by the accumulation of glycosaminoglycans due to deficiencies in the lysosomal enzymes responsible for their catabolism. Current treatments are not fully effective and are not available for all MPS types. Accordingly, researchers have tested novel therapies for MPS, including nanotechnology-based enzyme delivery systems and gene therapy. In this review, we aim to analyze some of the approaches involving nanotechnology as alternative treatments for MPS. Areas covered: We analyze nanotechnology-based systems, focusing on the biomaterials, such as polymers and lipids, that comprise these nanostructures, and we have highlighted studies that describe their use as enzyme and gene delivery systems for the treatment of MPS diseases. Expert opinion: Some protocols, such as the use of polymer-based systems or nanostructured carriers associated with enzymes and nanotechnology-based carriers for gene therapy, along with combined approaches, seem to be the future of MPS therapy.

Pentyl Gallate Nanoemulsions as Potential Topical Treatment of Herpes Labialis.

Previous studies have demonstrated the antiherpes activity of pentyl gallate (PG), suggesting that it could be a promising candidate for the topical treatment of human herpes labialis. PG low aqueous solubility represents a major drawback to its incorporation in topical dosage forms. Hence, the feasibility of incorporating PG into nanoemulsions, the ability to penetrate the skin, to inhibit herpes simplex virus (HSV)-1 replication, and to cause dermal sensitization or toxicity were evaluated. Oil/water nanoemulsions containing 0.5% PG were prepared by spontaneous emulsification. The in vitro PG distribution into porcine ear skin after topical application of nanoemulsions was assessed, and the in vitro antiviral activity against HSV-1 replication was evaluated. Acute dermal toxicity and risk of dermal sensitization were evaluated in rat model. Nanoemulsions presented nanometric particle size (from 124.8 to 143.7 nm), high zeta potential (from -50.1 to -66.1 mV), loading efficiency above 99%, and adequate stability during 12 months. All formulations presented anti-HSV-1 activity. PG was able to reach deeper into the dermis more efficiently from the nanoemulsion F4. This formulation as well as PG were considered safe for topical use. Nanoemulsions seem to be a safe and effective approach for topically delivering PG in the treatment of human herpes labialis infection.

A bioanalytical HPLC method for coumestrol quantification in skin permeation tests followed by UPLC-QTOF/HDMS stability-indicating method for identification of degradation products.

Coumestrol is present in several species of the Fabaceae family widely distributed in plants. The estrogenic and antioxidant activities of this molecule show its potential as skin anti-aging agent. These characteristics reveal the interest in developing analytical methodology for permeation studies, as well as to know the stability of coumestrol identifying the major degradation products. Thus, the present study was designed, first, to develop and validate a versatile liquid chromatography (HPLC) method to quantify coumestrol in a hydrogel formulation in different porcine skin layers (stratum corneum, epidermis, and dermis) in permeation tests. In the stability-indicating test coumestrol samples were exposed to stress conditions: temperature, UVC light, oxidative, acid and alkaline media. The degradation products, as well as the constituents extracted from the hydrogel, adhesive tape or skin were not eluted in the retention time of the coumestrol. Hence, the HPLC method showed to be versatile, specific, accurate, precise and robust showing excellent performance for quantifying coumestrol in complex matrices involving skin permeation studies. Coumestrol recovery from porcine ear skin was found to be in the range of 97.07-107.28 µg/mL; the intra-day precision (repeatability) and intermediate precision (inter-day precision), respectively lower than 4.71% and 2.09%. The analysis using ultra-performance liquid chromatography coupled to a quadrupole time-of-flight high definition mass spectrometry detector (UPLC-QTOF/HDMS) suggest the MS fragmentation patterns and the chemical structure of the main degradation products. These results represent new and relevant findings for the development of coumestrol pharmaceutical and cosmetic products.

A versatile, stability-indicating and high-throughput ultra-fast liquid chromatography method for the determination of isoflavone aglycones in soybeans, topical formulations, and permeation assays.

There is a growing interest in the pharmaceutical field concerning isoflavones topical delivery systems, especially with regard to their skin care properties and antiherpetic activity. In this context, the present work describes an ultra-fast liquid chromatography method (UFLC) for determining daidzein, glycitein, and genistein in different matrices during the development of topical systems containing isoflavone aglycones (IA) obtained from soybeans. The method showed to be specific, precise, accurate, and linear (0.1 to 5 µg mL(-1)) for IA determination in soybean acid extract, IA-rich fraction obtained after the purification process, IA loaded-nanoemulsions, and topical hydrogel, as well as for permeation/retention assays in porcine skin and porcine esophageal mucosa. The matrix effect was determined for all complex matrices, demonstrating low effect during the analysis. The stability indicating UFLC method was verified by submitting IA to acidic, alkaline, oxidative, and thermal stress conditions, and no interference of degradation products was detected during analysis. Mass spectrometry was performed to show the main compounds produced after acid hydrolysis of soybeans, as well as suggest the main degradation products formed after stress conditions. Besides the IA, hydroxymethylfurfural and ethoxymethylfurfural were produced and identified after acid hydrolysis of the soybean extract and well separated by the UFLC method. The method's robustness was confirmed using the Plackett-Burman experimental design. Therefore, the new method affords fast IA analysis during routine processes, extract purification, products development, and bioanalytical assays.

Determination of ß-caryophyllene skin permeation/retention from crude copaiba oil (Copaifera multijuga Hayne) and respective oil-based nanoemulsion using a novel HS-GC/MS method.

Copaiba oil is largely used in the Amazonian region for the treatment of inflammation, and recent studies demonstrated that one of the major components of the oil, ß-caryophyllene (CAR), is a potent anti-inflammatory. The nanoemulsification of this oleoresin, which has unctuous character, converts it in a more acceptable hydrophilic formulation and may improve CAR penetration through the skin due to the small droplet size and the high contact surface afforded by the nanoemulsions. This paper describes the validation of a novel, sensitive, practical and solvent free method that uses gas chromatography in headspace mode coupled with mass spectrometry to evaluate the skin permeation/retention of CAR from the crude copaiba oil and its nanoemulsion. Our results show that the bioanalytic method was fully validated, demonstrating linearity (r(2)>0.99), specificity (no peaks co-eluting with CAR retention time), precision (RSD<15%) and accuracy (recovery>90%) within the accepted parameters and that the copaiba oil nanoemulsion presented a better skin penetration compared to the crude oil, with CAR achieving the most profound layer of the skin, the dermis.