RESUMO
Recent advances have been reported for needle-free local anesthesia in maxillary teeth by administering a nasal spray of tetracaine (TTC) and oxymetazoline, without causing pain, fear, and stress. This work aimed to assess whether a TTC-loaded hybrid system could reduce cytotoxicity, promote sustained permeation, and increase the anesthetic efficacy of TTC for safe, effective, painless, and prolonged analgesia of the maxillary teeth in dental procedures. The hybrid system based on TTC (4%) encapsulated in nanostructured lipid carriers (NLC) and incorporated into a thermoreversible hydrogel of poloxamer 407 (TTCNLC-HG4%) displayed desirable rheological, mechanical, and mucoadhesive properties for topical application in the nasal cavity. Compared to control formulations, the use of TTCNLC-HG4% slowed in vitro permeation of the anesthetic across the nasal mucosa, maintained cytotoxicity against neuroblastoma cells, and provided a three-fold increase in analgesia duration, as observed using the tail-flick test in mice. The results obtained here open up perspectives for future clinical evaluation of the thermoreversible hybrid hydrogel, which contains TTC-loaded NLC, with the aim of creating an effective, topical, intranasal, needle-free anesthesia for use in dentistry.
RESUMO
Tetracaine (TTC) is a local anesthetic broadly used for topical and spinal blockade, despite its systemic toxicity. Encapsulation in nanostructured lipid carriers (NLC) may prolong TTC delivery at the site of injection, reducing such toxicity. This work reports the development of NLC loading 4% TTC. Structural properties and encapsulation efficiency (%EE > 63%) guided the selection of three pre-formulations of different lipid composition, through a 23 factorial design of experiments (DOE). DLS and TEM analyses revealed average sizes (193-220 nm), polydispersity (< 0.2), zeta potential |- 21.8 to - 30.1 mV| and spherical shape of the nanoparticles, while FTIR-ATR, NTA, DSC, XRD and SANS provided details on their structure and physicochemical stability over time. Interestingly, one optimized pre-formulation (CP-TRANS/TTC) showed phase-separation after 4 months, as predicted by Raman imaging that detected lack of miscibility between its solid (cetyl palmitate) and liquid (Transcutol) lipids. SANS analyses identified lamellar arrangements inside such nanoparticles, the thickness of the lamellae been decreased by TTC. As a result of this combined approach (DOE and biophysical techniques) two optimized pre-formulations were rationally selected, both with great potential as drug delivery systems, extending the release of the anesthetic (> 48 h) and reducing TTC cytotoxicity against Balb/c 3T3 cells.
Assuntos
Anestésicos Locais/farmacologia , Proliferação de Células , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Nanoestruturas/administração & dosagem , Tetracaína/farmacologia , Anestésicos Locais/química , Animais , Células 3T3 BALB , Camundongos , Nanoestruturas/química , Tetracaína/químicaRESUMO
Melanoma is the most aggressive skin carcinoma and nanotechnology can bring new options for its pharmacological treatment. Nanostructured lipid carriers (NLC) are ideal drug-delivery carriers for hydrophobic drugs, such as the antineoplastic docetaxel (DTX), and hybrid (NLC-in-hydrogel) systems are suitable for topical application. This work describes a formulation of NLCDTX in xanthan-chitosan hydrogel containing lidocaine (LDC) with anticancer and analgesia effects. The optimized nanoparticles encapsulated 96% DTX and rheological analysis revealed inherent viscoelastic properties of the hydrogel. In vitro assays over murine fibroblasts (NIH/3T3) and melanoma cells (B16-F10), human keratinocytes (HaCaT) and melanoma cells (SK-MEL-103) showed reduction of docetaxel cytotoxicity after encapsulation in NLCDTX and HGel-NLCDTX. Addition of LDC to the hybrid system (HGel-NLCDTX-LDC) increased cell death in tumor and normal cells. In vivo tests on C57BL/6J mice with B16-F10-induced melanoma indicated that LDC, NLCDTX, HGel-NLCDTX-LDC and NLCDTX + HGel-LDC significantly inhibited tumor growth while microPET/SPECT/CT data suggest better prognosis with the hybrid treatment. No adverse effects were observed in cell survival, weight/feed-consumption or serum biochemical markers (ALT, AST, creatinine, urea) of animals treated with NLCDTX or the hybrid system. These results confirm the adjuvant antitumor effect of lidocaine and endorse HGel-NLCDTX-LDC as a promising formulation for the topical treatment of melanoma.
RESUMO
In recent years, advanced nanohybrid materials processed as pharmaceuticals have proved to be very advantageous. Triptans, such as the commercially available intranasal sumatriptan (SMT), are drugs employed in the treatment of painful migraine symptoms. However, SMT effectiveness by the intranasal route is limited by its high hydrophilicity and poor mucoadhesion. Therefore, we designed hybrid nanoemulsions (NE) composed of copaiba oil as the organic component plus biopolymers (xanthan, pectin, alginate) solubilized in the continuous aqueous phase, aiming at the intranasal release of SMT (2% w/v). Firstly, drug-biopolymer complexes were optimized in order to decrease the hydrophilicity of SMT. The resultant complexes were further encapsulated in copaiba oil-based nanoparticles, forming NE formulations. Characterization by FTIR-ATR, DSC, and TEM techniques exposed details of the molecular arrangement of the hybrid systems. Long-term stability of the hybrid NE at 25°C was confirmed over a year, regarding size (~ 120 nm), polydispersity (~ 0.2), zeta potential (~ -25 mV), and nanoparticle concentration (~ 2.1014 particles/mL). SMT encapsulation efficiency in the formulations ranged between 41-69%, extending the in vitro release time of SMT from 5 h (free drug) to more than 24 h. The alginate-based NE was selected as the most desirable system and its in vivo nanotoxicity was evaluated in a zebrafish model. Hybrid NE treatment did not affect spontaneous movement or induce morphological changes in zebrafish larvae, and there was no evidence of mortality or cardiotoxicity after 48 h of treatment. With these results, we propose alginate-based nanoemulsions as a potential treatment for migraine pain.
RESUMO
Anesthetic failure is common in dental inflammation processes, even when modern agents, such as articaine, are used. Nanostructured lipid carriers (NLC) are systems with the potential to improve anesthetic efficacy, in which active excipients can provide desirable properties, such as anti-inflammatory. Coupling factorial design (FD) for in vitro formulation development with in vivo zebrafish tests, six different NLC formulations, composed of synthetic (cetyl palmitate/triglycerides) or natural (avocado butter/olive oil/copaiba oil) lipids were evaluated for loading articaine. The formulations selected by FD were physicochemically characterized, tested for shelf stability and in vitro release kinetics and had their in vivo effect (anti-inflammatory and anesthetic effect) screened in zebrafish. The optimized NLC formulation composed of avocado butter, copaiba oil, Tween 80 and 2% articaine showed adequate physicochemical properties (size = 217.7 ± 0.8 nm, PDI = 0.174 ± 0.004, zeta potential = - 40.2 ± 1.1 mV, %EE = 70.6 ± 1.8) and exhibited anti-inflammatory activity. The anesthetic effect on touch reaction and heart rate of zebrafish was improved to 100 and 60%, respectively, in comparison to free articaine. The combined FD/zebrafish approach was very effective to reveal the best articaine-in-NLC formulation, aiming the control of pain at inflamed tissues.
Assuntos
Anestesia/métodos , Anti-Inflamatórios/farmacologia , Bradicardia/tratamento farmacológico , Carticaína/farmacologia , Portadores de Fármacos/química , Inflamação/tratamento farmacológico , Nanoestruturas/química , Anestésicos Locais/química , Anestésicos Locais/farmacologia , Animais , Anti-Inflamatórios/química , Carticaína/química , Liberação Controlada de Fármacos , Excipientes/química , Nanoestruturas/administração & dosagem , Peixe-ZebraRESUMO
BACKGROUND: Extracellular vesicles (EVs) are lipid-bound particles that are naturally released from cells and mediate cell-cell communication. Integrin adhesion receptors are enriched in small EVs (SEVs) and SEV-carried integrins have been shown to promote cancer cell migration and to mediate organ-specific metastasis; however, how integrins mediate these effects is not entirely clear and could represent a combination of EV binding to extracellular matrix and cells. METHODS: To probe integrin role in EVs binding and uptake, we employed a disintegrin inhibitor (DisBa-01) of integrin binding with specificity for αvß3 integrin. EVs were purified from MDA-MB-231 cells conditioned media by serial centrifugation method. Isolated EVs were characterized by different techniques and further employed in adhesion, uptake and co-culture experiments. RESULTS: We find that SEVs secreted from MDA-MB-231 breast cancer cells carry αvß3 integrin and bind directly to fibronectin-coated plates, which is inhibited by DisBa-01. SEV coating on tissue culture plates also induces adhesion of MDA-MB-231 cells, which is inhibited by DisBa-01 treatment. Analysis of EV uptake and interchange between cells reveals that the amount of CD63-positive EVs delivered from malignant MDA-MB-231 breast cells to non-malignant MCF10A breast epithelial cells is reduced by DisBa-01 treatment. Inhibition of αvß3 integrin decreases CD63 expression in cancer cells suggesting an effect on SEV content. CONCLUSION: In summary, our findings demonstrate for the first time a key role of αvß3 integrin in cell-cell communication through SEVs. Video Abstract.
Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Vesículas Extracelulares/metabolismo , Integrina alfaVbeta3/metabolismo , Mama/patologia , Adesão Celular , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Vesículas Extracelulares/ultraestrutura , Feminino , Proteínas de Fluorescência Verde/metabolismo , Humanos , Modelos Biológicos , Ligação ProteicaRESUMO
Topical anesthetics are widely applied in order to relieve the discomfort and anxiety caused by needle insertion and other painful superficial interventions at the oral cavity. So far, there are no commercially available effective topical anesthetic formulations for that purpose, and the most of developments are related to hydrophilic and low mucoadhesive forms. Therefore, we have prepared different hybrid nanofilms composed of biopolymer matrices (chitosan, pectin, and chitosan-pectin) blended with nanostructured lipid carriers (NLC) loading the eutectic mixture of 5% lidocaine-prilocaine (LDC-PLC), in order to fulfill this gap in the market. These dual systems were processed as hybrid nanofilms by the solvent/casting method, and its mucoadhesive, structural and mechanical properties were detailed. The most appropriate hybrid nanofilm combined the advantages of both pectin (PCT) and NLC components. The resultant material presented sustained LDC-PLC release profile for more than 8 h; permeation across porcine buccal mucosa almost twice higher than control and non-cytotoxicity against 3T3 and HACAT cell lines. Then, the in vivo efficacy of PCT/NLC formulation was compared to biopolymer film and commercial drug, exhibiting the longest-lasting anesthetic effect (> 7 h), assessed by tail flick test in mice. These pectin-based hybrid nanofilms open perspectives for clinical trials and applications beyond Dentistry.
Assuntos
Anestesia Local/métodos , Anestésicos Locais/uso terapêutico , Odontologia/métodos , Portadores de Fármacos/uso terapêutico , Nanoestruturas/uso terapêutico , Dor/prevenção & controle , Células 3T3 , Anestésicos Locais/farmacologia , Animais , Biopolímeros/uso terapêutico , Células HaCaT , Humanos , Combinação Lidocaína e Prilocaína/farmacologia , Combinação Lidocaína e Prilocaína/uso terapêutico , Camundongos , Mucosa Bucal/efeitos dos fármacos , SuínosRESUMO
Finding an ideal anesthetic agent for postoperative pain control, with long action and low side effects, is still a challenge. Local anesthetics have potential for such application if their time of action is improved. This work introduces a new hybrid formulation formed by the association of a nanostructured lipid carrier with a biopolymeric system to encapsulate bupivacaine (BVC). The hybrid formulation was physicochemical and structurally characterized by DLS, TEM, DSC, XRD and FTIR-ATR, and it remained stable for 12 months at room temperature. In vivo analgesia and imaging tests showed that the hybrid system was able to modulate the release, and to increase the concentration of BVC at the site of action, by forming a nanogel in situ. Such nanogel improved over 5 times (>24 h) the anesthesia duration, when compared to free BVC at clinical (0.5%) doses. Therefore, this novel in situ-forming nanogel shows great potential to be used in postsurgical pain control, improving the action of BVC, without losing its versatility of (infiltrative) application.
Assuntos
Anestésicos Locais , Bupivacaína , Nanoestruturas , Alginatos/química , Alginatos/farmacologia , Anestésicos Locais/química , Anestésicos Locais/farmacocinética , Anestésicos Locais/farmacologia , Animais , Bupivacaína/química , Bupivacaína/farmacocinética , Bupivacaína/farmacologia , Implantes de Medicamento/química , Implantes de Medicamento/farmacocinética , Implantes de Medicamento/farmacologia , Géis , Masculino , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Ratos , Ratos WistarRESUMO
Inflammatory conditions of the temporomandibular joint (TMJ) and peripheral tissues affect many people around the world and are commonly treated with non-steroidal anti-inflammatory drugs (NSAIDs). However, in order to get desirable results, treatments with NSAIDs may take weeks, causing undesirable side effects and requiring repeated administration. In this sense, this work describes the development of an optimized nanostructured lipid carrier (NLC) formulation for intra-articular administration of naproxen (NPX). An experimental design (23) selected the best formulation in terms of its physicochemical and structural properties, elucidated by different methods (DLS, NTA, TEM, DSC, and ATR-FTIR). The chosen formulation (NLC-NPX) was tested on acute inflammatory TMJ nociception, in a rat model. The optimized excipients composition provided higher NPX encapsulation efficiency (99.8%) and the nanoparticles were found stable during 1 year of storage at 25 °C. In vivo results demonstrated that the sustained delivery of NPX directly in the TMJ significantly reduced leukocytes migration and levels of pro-inflammatory cytokines (IL-1ß and TNF-α), for more than a week. These results point out the NLC-NPX formulation as a promising candidate for the safe treatment of inflammatory pain conditions of TMJ or other joints.
Assuntos
Portadores de Fármacos/química , Naproxeno/administração & dosagem , Articulação Temporomandibular/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Movimento Celular/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Portadores de Fármacos/uso terapêutico , Leucócitos/efeitos dos fármacos , Leucócitos/patologia , Nanoestruturas , Nociceptividade/efeitos dos fármacos , Ratos , Articulação Temporomandibular/patologiaRESUMO
Nanostructured lipid carriers (NLC) belong to youngest lipid-based nanocarrier class and they have gained increasing attention over the last ten years. NLCs are composed of a mixture of solid and liquid lipids, which solubilizes the active pharmaceutical ingredient, stabilized by a surfactant. The miscibility of the lipid excipients and structural changes (polymorphism) play an important role in the stability of the formulation and are not easily predicted in the early pharmaceutical development. Even when the excipients are macroscopically miscible, microscopic heterogeneities can result in phase separation during storage, which is only detected after several months of stability studies. In this sense, this work aimed to evaluate the miscibility and the presence of polymorphism in lipid mixtures containing synthetic (cetyl palmitate, Capryol 90®, Dhaykol 6040 LW®, Precirol ATO5® and myristyl myristate) and natural (beeswax, cocoa and shea butters, copaiba, sweet almond, sesame and coconut oils) excipients using Raman mapping and multivariate curve resolution - alternating least squares (MCR-ALS) method. The results were correlated to the macroscopic stability of the formulations. Chemical maps constructed for each excipient allowed the direct comparison among formulations, using standard deviation of the histograms and the Distributional Homogeneity Index (DHI). Lipid mixtures of cetyl palmitate/Capryol®; cetyl palmitate/Dhaykol®; myristyl myristate/Dhaykol® and myristyl myristate/coconut oil presented a single histogram distribution and were stable. The sample with Precirol®/Capryol® was not stable, although the histogram distribution was narrower than the samples with cetyl palmitate, indicating that miscibility was not the factor responsible for the instability. Structural changes before and after melting were identified for cocoa butter and shea butter, but not in the beeswax. Beeswax + copaiba oil sample was very homogenous, without polymorphism and stable over 6â¯months. Shea butter was also homogeneous and, in spite of the polymorphism, was stable. Formulations with cocoa butter presented a wider histogram distribution and were unstable. This paper showed that, besides the miscibility evaluation, Raman imaging could also identify the polymorphism of the lipids, two major issues in lipid-based formulation development that could help guide the developer understand the stability of the NLC formulations.
Assuntos
Portadores de Fármacos/química , Lipídeos/química , Nanopartículas/química , Diglicerídeos/química , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes/química , Análise Multivariada , Miristatos/química , Palmitatos/química , Tamanho da Partícula , Óleos de Plantas/química , Polímeros/química , Propilenoglicóis/química , Solubilidade , Análise Espectral Raman , Tensoativos/química , Ceras/químicaRESUMO
Dibucaine (DBC) is among the more potent long-acting local anesthetics (LA), and it is also one of the most toxic. Over the last decades, solid lipid nanoparticles (SLN) have been developed as promising carriers for drug delivery. In this study, SLN formulations were prepared with the aim of prolonging DBC release and reducing its toxicity. To this end, SLN composed of two different lipid matrices and prepared by two different hot-emulsion techniques (high-pressure procedure and sonication) were compared. The colloidal stability of the SLN formulations was tracked in terms of particle size (nm), polydispersity index (PDI), and zeta potential (mV) for 240 days at 4 °C; the DBC encapsulation efficiency was determined by the ultrafiltration/centrifugation method. The formulations were characterized by differential scanning calorimetry (DSC), electron paramagnetic resonance (EPR), and release kinetic experiments. Finally, the in vitro cytotoxicity against 3T3 fibroblast and HaCaT cells was determined, and the in vivo analgesic action was assessed using the tail flick test in rats. Both of the homogenization procedures were found suitable to produce particles in the 200 nm range, with good shelf stability (240 days) and high DBC encapsulation efficiency (~72â»89%). DSC results disclosed structural information on the nanoparticles, such as the lower crystallinity of the lipid core vs. the bulk lipid. EPR measurements provided evidence of DBC partitioning in both SLNs. In vitro (cytotoxicity) and in vivo (tail flick) experiments revealed that the encapsulation of DBC into nanoparticles reduces its intrinsic cytotoxicity and prolongs the anesthetic effect, respectively. These results show that the SLNs produced are safe and have great potential to extend the applications of dibucaine by enhancing its bioavailability.
RESUMO
Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 µM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC.
Assuntos
Anestésicos Locais/farmacocinética , Anestésicos Locais/toxicidade , Dibucaína/farmacocinética , Dibucaína/toxicidade , Atividade Motora/efeitos dos fármacos , Medição da Dor/efeitos dos fármacos , Animais , Células 3T3 BALB , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Liberação Controlada de Fármacos , Lipossomos , Masculino , Camundongos , Atividade Motora/fisiologia , Medição da Dor/métodos , Fosfatidilcolinas/farmacocinética , Fosfatidilcolinas/toxicidade , Peixe-ZebraRESUMO
BACKGROUND: Topical drug administration offers an attractive route with minimal invasiveness. It also avoids limitations of intravenous administration such as the first pass metabolism and presystemic elimination within the gastrointestinal tract. Furthermore, topical drug administration is safe, have few side effects, is easy to apply, and offers a fast onset of action. However, the development of effective topical formulations still represents a challenge for the desired effect to be reached, locally or systemically. Solid lipid nanoparticles and nanostructured lipid carriers are particular candidates to overcome the problem of topical drug administration. The nanometric particle size of lipid nanoparticles favors the physical adhesion to the skin or mucosal, what can also be attained with the formation of hybrid (nanoparticles/polymer) systems. METHODS: In this review, we discuss the major challenges for lipid nanoparticles formulations for topical application to oral mucosa, skin, and eye, highlighting the strategies to improve the performance of lipid nanoparticles for topical applications. Next, we critically analyzed the in vitro and in vivo approaches used to evaluate lipid nanoparticles performance and toxicity. CONCLUSION: We addressed some major drawbacks related to lipid nanoparticle topical formulations and concluded the key points that have to be overcome to help them to reach the market in topical formulations to oral mucosa, skin and eye.
RESUMO
The short time of action and systemic toxicity of local anaesthetics limit their clinical application. Bupivacaine is the most frequently used local anaesthetic in surgical procedures worldwide. The discovery that its S(-) enantiomeric form is less toxic than the R(+) form led to the introduction of products with enantiomeric excess (S75:R25 bupivacaine) in the market. Nevertheless, the time of action of bupivacaine is still short; to overcome that, bupivacaine S75:R25 (BVCS75) was encapsulated in nanostructured lipid carriers (NLC). In this work, we present the development of the formulation using chemometric tools of experimental design to study the formulation factors and Raman mapping associated with Classical Least Squares (CLS) to study the miscibility of the solid and the liquid lipids. The selected formulation of the nanostructured lipid carrier containing bupivacaine S75:R25 (NLCBVC) was observed to be stable for 12 months under room conditions regarding particle size, polydispersion, Zeta potential and encapsulation efficiency. The characterisation by DSC, XDR and TEM confirmed the encapsulation of BVCS75 in the lipid matrix, with no changes in the structure of the nanoparticles. The in vivo analgesic effect elicited by NLCBVC was twice that of free BVCS75. Besides improving the time of action, no statistical difference in the blockage of the sciatic nerve of rats was found between 0.125% NLCBVC and 0.5% free BVCS75. Therefore, the formulation allows a reduction in the required anaesthesia dose, decreasing the systemic toxicity of bupivacaine, and opening up new possibilities for different clinical applications.
Assuntos
Anestésicos Locais/farmacologia , Bupivacaína/farmacologia , Portadores de Fármacos/química , Nanoestruturas/química , Animais , Lipídeos/química , Nanotecnologia , Ratos , Nervo Isquiático/efeitos dos fármacosRESUMO
In a nanotechnological approach we have investigated the use of natural lipids in the preparation of nanostructured lipid carriers (NLC). Three different NLC composed of copaiba oil and beeswax, sweet almond oil and shea butter, and sesame oil and cocoa butter as structural matrices were optimized using factorial analysis; Pluronic® 68 and lidocaine (LDC) were used as the colloidal stabilizer and model encapsulated drug, respectively. The optimal formulations were characterized by different techniques (IR-ATR, DSC, and TEM), and their safety and efficacy were also tested. These nanocarriers were able to upload high amounts of the anesthetic with a sustained in vitro release profile for 24h. The physicochemical stability in terms of size (nm), PDI, zeta potential (mV), pH, nanoparticle concentration (particles/mL), and visual inspection was followed during 12months of storage at 25°C. The formulations exhibited excellent structural properties and stability. They proved to be nontoxic in vitro (cell viability tests with Balb/c 3T3 fibroblasts) and significantly improved the in vivo effects of LDC, over the heart rate of zebra fish larvae and in the blockage of sciatic nerve in mice. The results from this study support that the proper combination of natural excipients is promising in DDS, taking advantage of the biocompatibility, low cost, and diversity of lipids.
Assuntos
Portadores de Fármacos/química , Lidocaína/farmacocinética , Lipídeos/química , Poloxâmero/química , Ceras/química , Animais , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Excipientes/química , Humanos , Lidocaína/administração & dosagem , Lidocaína/química , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/química , Tamanho da Partícula , Óleos de Plantas/química , Propriedades de Superfície , Peixe-ZebraRESUMO
In dental practice, local anesthesia causes pain, fear, and stress, and is frequently the reason that patients abandon treatment. Topical anesthetics are applied in order to minimize the discomfort caused by needle insertion and injection, and to reduce the symptoms of superficial trauma at the oral mucosa, but there are still no efficient commercially available formulations. Factorial design is a multivariate data analysis procedure that can be used to optimize the manufacturing processes of lipid nanocarriers, providing valuable information and minimizing development time. This work describes the use of factorial design to optimize a process for the preparation of nanostructured lipid carriers (NLC) based on cetyl palmitate and capric/caprylic triglycerides as structural lipids and Pluronic 68 as the colloidal stabilizer, for delivery of the local anesthetics lidocaine and prilocaine (both at 2.5%). The factors selected were the excipient concentrations, and three different responses were followed: particle size, polydispersity index and zeta potential. The encapsulation efficiency of the most effective formulations (NLC 2, 4, and 6) was evaluated by the ultrafiltration/centrifugation method. The formulations that showed the highest levels of encapsulation were tested using in vitro release kinetics experiments with Franz diffusion cells. The NLC6 formulation exhibited the best sustained release profile, with 59% LDC and 66% PLC released after 20h. This formulation was then characterized using different techniques (IR-ATR, DSC, DRX, TEM, and NTA) to obtain information about its molecular organization and its physicochemical stability, followed during 14months of storage at 25°C. This thorough pre-formulation study represents an important advance towards the development of an efficient pre-anesthetic for use in dentistry.
Assuntos
Anestésicos Locais/química , Portadores de Fármacos/química , Lidocaína/química , Nanoestruturas/química , Prilocaína/química , Administração Tópica , Química Farmacêutica , Liberação Controlada de Fármacos , Lipídeos/químicaRESUMO
New magnetic bio-hybrid matrices for potential application in drug delivery are developed from the assembly of the biopolymer alginate and magnetic graphite nanoparticles. Ibuprofen (IBU) intercalated in a Mg-Al layered double hydroxide (LDH) was chosen as a model drug delivery system (DDS) to be incorporated as third component of the magnetic bionanocomposite DDS. For comparative purposes DDS based on the incorporation of pure IBU in the magnetic bio-hybrid matrices were also studied. All the resulting magnetic bionanocomposites were processed as beads and films and characterized by different techniques with the aim to elucidate the role of the magnetic graphite on the systems, as well as that of the inorganic brucite-like layers in the drug-loaded LDH. In this way, the influence of both inorganic components on the mechanical properties, the water uptake ability, and the kinetics of the drug release from these magnetic systems were determined. In addition, the possibility of modulating the levels of IBU release by stimulating the bionanocomposites with an external magnetic field was also evaluated in in vitro assays.
Assuntos
Alginatos/química , Portadores de Fármacos/química , Grafite/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Hidróxidos/administração & dosagem , Hidróxidos/química , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Propriedades de SuperfícieRESUMO
This work introduces results on a new drug delivery system (DDS) based on the use of chitosan/layered double hydroxide (LDH) biohybrid beads coated with pectin for controlled release in the treatment of colon diseases. Thus, the 5-aminosalicylic acid (5ASA), the most used non-steroid-anti-inflammatory drug (NSAID) in the treatment of ulcerative colitis and Crohn's disease, was chosen as model drug aiming to a controlled and selective delivery in the colon. The pure 5ASA drug and the hybrid material prepared by intercalation in a layered double hydroxide of Mg2Al using the co-precipitation method, were incorporated in a chitosan matrix in order to profit from its mucoadhesiveness. These compounds processed as beads were further treated with the polysaccharide pectin to create a protective coating that ensures the stability of both chitosan and layered double hydroxide at the acid pH of the gastric fluid. The resulting composite beads presenting the pectin coating are stable to water swelling and procure a controlled release of the drug along their passage through the simulated gastrointestinal tract in in vitro experiments, due to their resistance to pH changes. Based on these results, the pectin@chitosan/LDH-5ASA bionanocomposite beads could be proposed as promising candidates for the colon-targeted delivery of 5ASA, with the aim of acting only in the focus of the disease and minimizing side effects.