RESUMO
Binder jetting (BJ) three-dimensional (3D) printing is becoming an established additive manufacturing technology for manufacturing of solid products for oral drug delivery. Similar to traditional solutions based on compaction of powder mixture, successful processing of BJ products requires control of bulk powder properties. In contrast to traditional compaction-based process, BJ 3D printing allows for flexible modifications on microstructure, material composition and dose in the printed pharmaceutical products. Currently, systematic strategies for selecting excipients and optimizing the printing process have not been fully established. To address this challenge, a summary of the published work and selected patent literature around BJ 3D printing to fabricate pharmaceutical solid products for oral administration purposes is presented. First, an overview of characteristics of printed products as a part of the product design and a description of the commonly used excipients and active pharmaceutical ingredients is given. The critical powder and ink properties, as well as physical geometries and inner structures of a final product, are discussed in term of the mechanisms that determine the formation of a printed solid product and finally the quality of this product. This review is also summarizing the technical features of printers, printheads, and the critical considerations for post-processing procedures. BJ 3D printing is one of the most promising additive manufacturing technologies for mass customization of pharmaceutical products.
Assuntos
Excipientes , Tecnologia Farmacêutica , Excipientes/química , Preparações Farmacêuticas , Pós , Impressão Tridimensional , Tecnologia Farmacêutica/métodosRESUMO
Poor aqueous solubility is a common characteristic of new drug candidates, which leads to low or inconsistent oral bioavailability. This has sparked an interest in material efficient testing of solubility and dissolution rate. The aim was to develop a microgram scale video-microscopic method to screen the dissolution rates of poorly water-soluble drugs. This method was applied to six drugs (carvedilol, diazepam, dipyridamole, felodipine, fenofibrate, and indomethacin) in fasted state simulated intestinal fluid (FaSSIF), of indomethacin in buffer with varying pH, and of diazepam and dipyridamole in customized media. An additional aim was to track phase transformations for carbamazepine in FaSSIF. The dissolution rates and particle behavior of the drugs were investigated by tracking particle surface area over time using optical video-microscopy. Applying miniaturized UV spectroscopic dissolution resulted in a similar grouping of dissolution rates and pH effects, as for the video-microscopic setup. Using customized media showed that lysophospholipid enhanced the dissolution rate of diazepam and dipyridamole. The video-microscopic setup allowed for the nucleation of transparent particles on dissolving carbamazepine particles to be tracked over time. The developed setup offers a material efficient screening approach to group drugs according to dissolution rate, where the use of optical microscopy helps to achieve a high sample throughput.
Assuntos
Indometacina , Água , Carbamazepina , Diazepam , Dipiridamol , Solubilidade , Água/químicaRESUMO
Exosome selectivity mechanisms underlying exosome-target cell interactions and the specific traits affecting their capability to communicate still remain unclear. Moreover, the capacity of exosomes to efficiently deliver their molecular cargos intracellularly needs precise investigation towards establishing functional exosome-based delivery platforms exploitable in the clinical practice. The current study focuses on: (a) exosome production from normal MRC-5 and Vero cells growing in culture, (b) physicochemical characterization by dynamic light scattering (DLS) and cryo-transmission electron microscopy; (c) cellular uptake studies of rhodamine-labeled exosomes in normal and cancer cells, providing to exosomes either "autologous" or "heterologous" cellular delivery environments; and (d) loading exogenous Alexa Fluor 488-labeled siRNA into exosomes for the assessment of their delivering capacity by immunofluorescence in a panel of recipient cells. The data obtained thus far indicate that MRC-5 and Vero exosomes, indeed exhibit an interesting delivering profile, as promising "bio-shuttles," being pharmacologically exploitable in the context of theranostic applications.
Assuntos
Sistemas de Liberação de Medicamentos , Exossomos/química , MicroRNAs/uso terapêutico , RNA Interferente Pequeno/uso terapêutico , Animais , Comunicação Celular/genética , Linhagem Celular Tumoral , Chlorocebus aethiops , Microscopia Crioeletrônica , Exossomos/genética , Humanos , MicroRNAs/química , RNA Interferente Pequeno/química , Células VeroRESUMO
Micro-reservoir based drug delivery systems have the potential to provide targeted drug release locally in the intestine, i.e. at the inflamed areas of the intestine of patients with inflammatory bowel disease (IBD). In this study, microcontainers with a diameter of 300 µm and a height of 100 µm, asymmetrical geometry and the possibility to provide unidirectional release, are fabricated in the biodegradable polymer poly-É-caprolactone (PCL) using hot punching. As a first step towards local treatment of IBD, a novel method for loading of microcontainers with the corticosteroid budesonide is developed. For this purpose, a budesonide-Soluplus drug-polymer film is prepared by spin coating and loaded into the microcontainer reservoirs using hot punching. The processing parameters are optimized to achieve a complete loading of a large number of containers in a single step. A poly(lactic-co-glycolic acid) (PLGA) 50:50 lid is subsequently applied by spray coating. Solid-state characterization indicates that the drug is in an amorphous state in the drug-polymer films and the in vitro drug release profile showed a 68% release over 10 h. The results demonstrate that hot punching can be employed both as a production and loading method for PCL microcontainers with the perspective of local treatment of IBD.
Assuntos
Budesonida , Polietilenoglicóis , Sistemas de Liberação de Medicamentos , Humanos , PolivinilRESUMO
Mapping the spatial distribution of a drug throughout the gastrointestinal tract (GIT) after oral ingestion can provide novel insights into the interaction between the drug, the oral drug delivery system, and the GIT. Matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) is a molecular imaging technique that can analyze molecules in the cryosections of tissues, determining their localization with a spatial resolution of 10-100 µm. The overall aim of this study was to use MALDI-MSI to visualize the distribution and spatial location of a model prodrug (fenofibrate) through the rat GIT. Furthermore, the distribution and spatial colocalization of taurocholate and phospholipids in the rat GIT in relation to fenofibrate were investigated. Rats were given a fenofibrate suspension of 10 mg/mL by oral gavage. Blood samples were drawn, and the rats were euthanized at three different time points. The GIT was collected and frozen, and MALDI-MSI was applied on cross sections of the stomach and intestine. Fenofibrate was detected by MALDI-MSI throughout the GIT, which also revealed that fenofibrate was hydrolyzed to the active drug fenofibric acid already in the stomach. Furthermore, the presence of lyso-phosphatidylcholine (lyso-PC) and taurocholate was confirmed in the lumen of the small intestine. MALDI-MSI was shown to be a useful qualitative tool for localizing parent prodrugs and active drugs, with a possibility for gaining insight into not only the location for activation but also the role of endogenous molecules in the process.
Assuntos
Fenofibrato/análogos & derivados , Trato Gastrointestinal/metabolismo , Imagem Molecular/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Administração Oral , Animais , Fenofibrato/administração & dosagem , Fenofibrato/análise , Fenofibrato/farmacocinética , Masculino , Modelos Animais , Pró-Fármacos , Ratos , Análise Espacial , Suspensões , Distribuição TecidualRESUMO
Drug release from a lipid-based drug delivery system (LbDDS) is typically studied in vitro using a one-step intestinal digestion model. However, lately the importance of incorporating gastric digestion has been stressed. The aim of the present study was to compare a two-step gastro-intestinal (GI) in vitro digestion model to the commonly used one-step intestinal digestion model. The models were evaluated by studying release of the model drug A1260 from two LbDDSs (F-I and F-II), for which in vivo pharmacokinetic data from oral administration to beagle dogs were available. The amount of A1260 recovered in the aqueous phases during and after the GI digestion of F-I and F-II was related to the Cmax and AUC0-48h of the plasma concentration-time profiles of each formulation and produced a rank order in vitro-in vivo (IVIV) relation. In comparison, a similar IVIV rank ordering was obtained when relating the amount of A1260 recovered in the aqueous phase prior (t = 0 min), and following 15 min of intestinal digestion, to the plasma concentration-time profiles. However, after 60 min of intestinal digestion, the LbDDSs performed equally in the one-step in vitro digestion model, contrary to what was observed in the two-step digestion model, and in vivo. As the GI digestion model produced a clearer distinction in terms of LbDDS rank ordering of the two LbDDSs, compared to the intestinal digestion model, it was found to be a promising in vitro model to study and estimate the LbDDS behavior in vivo.
Assuntos
Digestão/fisiologia , Intestinos/fisiologia , Lipídeos/farmacocinética , Preparações Farmacêuticas/metabolismo , Estômago/fisiologia , Animais , Química Farmacêutica/métodos , Cães , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Modelos Biológicos , SolubilidadeRESUMO
The use of co-amorphous systems containing a combination of low molecular weight drugs and excipients is a relatively new technology in the pharmaceutical field to improve the solubility of poorly water-soluble drugs. However, some co-amorphous systems show a lower glass transition temperature ( Tg) than many of their polymeric solid dispersion counterparts. In this study, we aimed at designing a stable co-amorphous system with an elevated Tg. Carbamazepine (CBM) and citric acid (CA) were employed as the model drug and the coformer, respectively. co-amorphous CBM-CA at a 1:1 molar ratio was formed by ball milling, but a transition from the glassy to the supercooled melt state was observed under ambient conditions, due to the relatively low Tg of 38.8 °C of the co-amorphous system and moisture absorption. To improve the Tg of the coformer, salt formation of a combination of l-arginine (ARG) with CA was studied. First, ball milling of CA-ARG at molar ratios of 1:1, 1:2, and 1:3 forming co-amorphous systems was performed and led to a dramatic enhancement of the Tg, depending on the CA-ARG ratio. Salt formation between CA and ARG was observed by infrared spectroscopy. Next, ball milling of CBM-CA-ARG at molar ratios of 1:1:1, 1:1:2, and 1:1:3 resulted in co-amorphous blends, which had a single Tg at 77.8, 105.3, and 127.8 °C, respectively. These ternary co-amorphous samples remained in a solid amorphous form for 2 months at 40 °C. From these results, it can be concluded that blending of the salt coformer with a drug is a promising strategy to design stable co-amorphous formulations.
Assuntos
Arginina/química , Carbamazepina/química , Ácido Cítrico/química , Vidro/química , Cloreto de Sódio/química , Química Farmacêutica/métodos , Excipientes/química , Solubilidade/efeitos dos fármacos , Tecnologia Farmacêutica/métodos , Temperatura de Transição/efeitos dos fármacosRESUMO
Many drug candidates today have a low aqueous solubility and, hence, may show a low oral bioavailability, presenting a major formulation and drug delivery challenge. One way to increase the bioavailability of these drugs is to use a supersaturating drug delivery strategy. The aim of this study was to develop a video-microscopic method, to evaluate the effect of a precipitation inhibitor on supersaturated solutions of the poorly soluble drug tadalafil, using a novel video-microscopic small scale setup. Based on preliminary studies, a degree of supersaturation of 29 was chosen for the supersaturation studies with tadalafil in FaSSIF. Different amounts of hydroxypropyl methyl cellulose (HPMC) were predissolved in FaSSIF to give four different concentrations, and the supersaturated system was then created using a solvent shift method. Precipitation of tadalafil from the supersaturated solutions was monitored by video-microscopy as a function of time. Single-particle analysis was possible using commercially available software; however, to investigate the entire population of precipitating particles (i.e., their number and area covered in the field of view), an image analysis algorithm was developed (multiparticle analysis). The induction time for precipitation of tadalafil in FaSSIF was significantly prolonged by adding 0.01% (w/v) HPMC to FaSSIF, and the maximum inhibition was reached at 0.1% (w/v) HPMC, after which additional HPMC did not further increase the induction time. The single-particle and multiparticle analyses yielded the same ranking of the HPMC concentrations, regarding the inhibitory effect on precipitation. The developed small scale method to assess the effect of precipitation inhibitors can speed up the process of choosing the right precipitation inhibitor and the concentration to be used.
Assuntos
Precipitação Química/efeitos dos fármacos , Excipientes/farmacologia , Derivados da Hipromelose/farmacologia , Tadalafila/farmacocinética , Algoritmos , Disponibilidade Biológica , Química Farmacêutica , Desenho de Fármacos , Excipientes/química , Derivados da Hipromelose/química , Microscopia de Vídeo/métodos , Modelos Químicos , Solubilidade , Solventes/química , Tadalafila/química , Água/químicaRESUMO
The high number of poorly water-soluble compounds in drug development has increased the need for enabling formulations to improve oral bioavailability. One frequently applied approach is to induce supersaturation at the absorptive site, e.g., the small intestine, increasing the amount of dissolved compound available for absorption. However, due to the stochastic nature of nucleation, supersaturating drug delivery systems may lead to inter- and intrapersonal variability. The ability to define a feasible range with respect to the supersaturation level is a crucial factor for a successful formulation. Therefore, an in vitro method is needed, from where the ability of a compound to supersaturate can be defined in a reproducible way. Hence, this study investigates the reproducibility of an in vitro small scale standardized supersaturation and precipitation method (SSPM). First an intralaboratory reproducibility study of felodipine was conducted, after which seven partners contributed with data for three model compounds; aprepitant, felodipine, and fenofibrate, to determine the interlaboratory reproducibility of the SSPM. The first part of the SSPM determines the apparent degrees of supersaturation (aDS) to investigate for each compound. Each partner independently determined the maximum possible aDS and induced 100, 87.5, 75, and 50% of their determined maximum possible aDS in the SSPM. The concentration-time profile of the supersaturation and following precipitation was obtained in order to determine the induction time (tind) for detectable precipitation. The data showed that the absolute values of tind and aDS were not directly comparable between partners, however, upon linearization of the data a reproducible rank ordering of the three model compounds was obtained based on the ß-value, which was defined as the slope of the ln(tind) versus ln(aDS)-2 plot. Linear regression of this plot showed that aprepitant had the highest ß-value, 15.1, while felodipine and fenofibrate had comparable ß-values, 4.0 and 4.3, respectively. Of the five partners contributing with full data sets, 80% could obtain the same rank order for the three model compounds using the SSPM (aprepitant > felodipine ≈ fenofibrate). The α-value is dependent on the experimental setup and can be used as a parameter to evaluate the uniformity of the data set. This study indicated that the SSPM was able to obtain the same rank order of the ß-value between partners and, thus, that the SSPM may be used to classify compounds depending on their supersaturation propensity.
Assuntos
Precipitação Química , Composição de Medicamentos/normas , Sistemas de Liberação de Medicamentos/normas , Aprepitanto , Disponibilidade Biológica , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Felodipino/química , Felodipino/farmacocinética , Fenofibrato/química , Fenofibrato/farmacocinética , Técnicas In Vitro/métodos , Técnicas In Vitro/normas , Morfolinas/química , Morfolinas/farmacocinética , Reprodutibilidade dos Testes , Solubilidade , Água/químicaRESUMO
Green, all-polysaccharide based microcapsules with mechanically robust capsule walls and fast, stimuli-triggered, and switchable permeability behavior show great promise in applications based on selective and timed permeability. Taking a cue from nature, the build-up and composition of plant primary cell walls inspired the capsule wall assembly, because the primary cell walls in plants exhibit high mechanical properties despite being in a highly hydrated state, primarily owing to cellulose microfibrils. The microcapsules (16 ± 4 µm in diameter) were fabricated using the layer-by-layer technique on sacrificial CaCO3 templates, using plant polysaccharides (pectin, cellulose nanofibers, and xyloglucan) only. In water, the capsule wall was permeable to labeled dextrans with a hydrodynamic diameter of â¼6.6 nm. Upon exposure to NaCl, the porosity of the capsule wall quickly changed allowing larger molecules (â¼12 nm) to permeate. However, the porosity could be restored to its original state by removal of NaCl, by which permeants became trapped inside the capsule's core. The high integrity of cell wall was due to the CNF and the ON/OFF alteration of the permeability properties, and subsequent loading/unloading of molecules, could be repeated several times with the same capsule demonstrating a robust microcontainer with controllable permeability properties.
Assuntos
Materiais Biomiméticos/química , Celulose/química , Portadores de Fármacos/química , Nanofibras/química , Carbonato de Cálcio/química , Cápsulas , Celulose/ultraestrutura , Liberação Controlada de Fármacos , Glucanos/química , Nanofibras/ultraestrutura , Pectinas/química , Permeabilidade , Porosidade , Propriedades de Superfície , Xilanos/químicaRESUMO
PURPOSE: A 3D printer was used to realise compartmental dosage forms containing multiple active pharmaceutical ingredient (API) formulations. This work demonstrates the microstructural characterisation of 3D printed solid dosage forms using X-ray computed microtomography (XµCT) and terahertz pulsed imaging (TPI). METHODS: Printing was performed with either polyvinyl alcohol (PVA) or polylactic acid (PLA). The structures were examined by XµCT and TPI. Liquid self-nanoemulsifying drug delivery system (SNEDDS) formulations containing saquinavir and halofantrine were incorporated into the 3D printed compartmentalised structures and in vitro drug release determined. RESULTS: A clear difference in terms of pore structure between PVA and PLA prints was observed by extracting the porosity (5.5% for PVA and 0.2% for PLA prints), pore length and pore volume from the XµCT data. The print resolution and accuracy was characterised by XµCT and TPI on the basis of the computer-aided design (CAD) models of the dosage form (compartmentalised PVA structures were 7.5 ± 0.75% larger than designed; n = 3). CONCLUSIONS: The 3D printer can reproduce specific structures very accurately, whereas the 3D prints can deviate from the designed model. The microstructural information extracted by XµCT and TPI will assist to gain a better understanding about the performance of 3D printed dosage forms.
Assuntos
Preparações Farmacêuticas/química , Poliésteres/química , Álcool de Polivinil/química , Química Farmacêutica/métodos , Desenho Assistido por Computador , Formas de Dosagem , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Fenantrenos/química , Porosidade , Impressão/métodos , Impressão Tridimensional , Tecnologia Farmacêutica/métodos , Imagem Terahertz/métodos , Microtomografia por Raio-X/métodos , Raios XRESUMO
The focus on drug delivery for the pediatric population has been steadily increasing in the last decades. In terms of developing in vitro models simulating characteristics of the targeted pediatric population, with the purpose of predicting drug product performance after oral administration, it is important to simulate the gastro-intestinal conditions and processes the drug will encounter upon oral administration. When a drug is administered in the fed state, which is commonly the case for neonates, as they are typically fed every 3 h, the digestion of the milk will affect the composition of the fluid available for drug dissolution/solubilization. Therefore, in order to predict the solubilized amount of drug available for absorption, an in vitro model simulating digestion in the gastro-intestinal tract should be utilized. In order to simulate the digestion process and the drug solubilization taking place in vivo, the following aspects should be considered; physiologically relevant media, media volume, use of physiological enzymes in proper amounts, as well as correct pH and addition of relevant co-factors, e.g., bile salts and co-enzymes. Furthermore, physiological transit times and appropriate mixing should be considered and mimicked as close as possible. This paper presents a literature review on physiological factors relevant for digestion and drug solubilization in neonates. Based on the available literature data, a novel in vitro digestion model simulating digestion and drug solubilization in the neonate and young infant pediatric population (2 months old and younger) was designed.
Assuntos
Digestão/fisiologia , Sistemas de Liberação de Medicamentos/métodos , Trato Gastrointestinal/metabolismo , Absorção Intestinal/fisiologia , Preparações Farmacêuticas/metabolismo , Administração Oral , Ácidos e Sais Biliares/metabolismo , Química Farmacêutica/métodos , Simulação por Computador , Humanos , Modelos Biológicos , Pediatria , SolubilidadeRESUMO
Microwells fabricated from poly-L-lactic acid (PLLA) were evaluated for their application as an oral drug delivery system using the amorphous sodium salt of furosemide (ASSF) as a model drug. Hot embossing of PLLA resulted in fabrication of microwells with an inner diameter of 240 µm and a height of 100 µm. The microwells were filled with ASSF using a modified screen printing technique, followed by coating of the microwell cavities with a gastro-resistant lid of Eudragit® L100. The release behavior of ASSF from the coated microwells was investigated using a µ-Diss profiler and a UV imaging system, and under conditions simulating the changing environment of the gastrointestinal tract. Biorelevant gastric medium (pH 1.6) was employed, after which a change to biorelevant intestinal release medium (pH 6.5) was carried out. Both µ-Diss profiler and UV imaging release experiments showed that sealing of microwell cavities with an Eudragit® layer prevented drug release in biorelevant gastric medium. An immediate release of the ASSF from coated microwells was observed in the intestinal medium. This pH-triggered release behavior demonstrates the future potential of PLLA microwells as a site-specific oral drug delivery system.
Assuntos
Implantes Absorvíveis , Implantes de Medicamento/síntese química , Furosemida/química , Suco Gástrico/química , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Polímeros/química , Administração Oral , Cápsulas , Difusão , Implantes de Medicamento/administração & dosagem , Furosemida/administração & dosagem , Humanos , Teste de Materiais , PoliésteresRESUMO
Selection of excipients for drug formulations requires both intellectual and experimental considerations as many of the used excipients are affected by physiological factors, e.g., they may be digested by pancreatic enzymes in the gastrointestinal tract. In the present paper we have looked systematically into the differences between Kolliphor ELP, EL, and RH40 and how they affect the bioavailability of fenofibrate, through pharmacokinetic studies in rats and in vitro lipolysis studies. The study design was made as simple as possible to avoid confounding factors, for which reason the tested formulations only comprised an aqueous micellar solution of the model drug (fenofibrate) in varying concentrations (2-25% (w/v)) of the three tested surfactants. Increased concentrations of Kolliphor ELP and EL led to increased fenofibrate AUC0-24h values. For the Kolliphor RH40 formulations, an apparent fenofibrate absorption optimum was seen at 15% (w/v) surfactant, displaying both the highest AUC0-24h and Cmax. The reduced absorption of fenofibrate from the formulation containing the highest level of surfactant (25% w/v) was thought to be caused by some degree of trapping within Kolliphor RH40 micelles. In vitro, Kolliphor ELP and EL were found to be more prone to digestion than Kolliphor RH40, though not affecting the in vivo results. The highest fenofibrate bioavailability was attained from formulations with high Kolliphor ELP/EL levels (25% (w/v)), indicating that these surfactants are the better choice for solubilizing fenofibrate in order to increase the absorption upon oral administration. Due to drug dependent effects of the different types of Kolliphor, more studies are recommended in order to understand which type of Kolliphor is best suited for a given drug.
Assuntos
Fenofibrato/administração & dosagem , Polietilenoglicóis/química , Tensoativos/química , Administração Oral , Animais , Área Sob a Curva , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão , Excipientes , Absorção Intestinal , Lipídeos , Lipólise , Masculino , Micelas , Tamanho da Partícula , Veículos Farmacêuticos , Ratos , Ratos Sprague-Dawley , Solubilidade , Óleo de Soja/químicaRESUMO
The aim of this study was to investigate if molecular interactions between the weak base cinnarizine and lipolysis products were affecting the morphology of precipitated drug formed during in vitro lipolysis. In vitro lipolysis studies of a self-nanoemulsifying drug delivery system with or without cinnarizine were conducted. The digestion phases (aqueous phase and pellet phase) were separated by ultracentrifugation, and the pellet was isolated and lyophilized. The lyophilized pellets were examined by X-ray powder diffraction, (13)C solid-state nuclear magnetic resonance ((13)C NMR), (1)H liquid-state NMR ((1)H NMR) spectroscopy and differential scanning calorimetry (DSC). The (13)C NMR data indicated that the carbonyl groups and aliphatic part of the lipids undergo structural changes when the pellet contains cinnarizine. The (1)H NMR data suggests interactions occurring around the nitrogens on cinnarizine and the carboxylic group of fatty acids. DSC thermograms showed cinnarizine to be homogeneously incorporated into the lipids of the pellet, and no free amorphous cinnarizine was present. The three techniques (13)C NMR, (1)H NMR, and DSC complement each other and suggest interactions to occur between fatty acids and cinnarizine, which in turn favors amorphous precipitation.
Assuntos
Bloqueadores dos Canais de Cálcio/química , Precipitação Química , Cinarizina/química , Sistemas de Liberação de Medicamentos , Lipídeos/química , Varredura Diferencial de Calorimetria , Química Farmacêutica , Portadores de Fármacos , Lipólise , Solubilidade , Fatores de TempoRESUMO
PURPOSE: Lipid-based formulations (LBF) are substrates for digestive lipases and digestion can significantly alter their properties and potential to support drug absorption. LBFs have been widely examined for their behaviour in the presence of pancreatic enzymes. Here, the impact of gastric lipase on the digestion of representative formulations from the Lipid Formulation Classification System has been investigated. METHODS: The pHstat technique was used to measure the lipolysis by recombinant dog gastric lipase (rDGL) of eight LBFs containing either medium (MC) or long (LC) chain triglycerides and a range of surfactants, at various pH values [1.5 to 7] representative of gastric and small intestine contents under both fasting and fed conditions. RESULTS: All LBFs were hydrolyzed by rDGL. The highest specific activities were measured at pH 4 with the type II and IIIA MC formulations that contained Tween®85 or Cremophor EL respectively. The maximum activity on LC formulations was recorded at pH 5 for the type IIIA-LC formulation. Direct measurement of LBF lipolysis using the pHstat, however, was limited by poor LC fatty acid ionization at low pH. CONCLUSIONS: Since gastric lipase initiates lipid digestion in the stomach, remains active in the intestine and acts on all representative LBFs, its implementation in future standardized in vitro assays may be beneficial. At this stage, however, routine use remains technically challenging.
Assuntos
Química Farmacêutica , Lipase/metabolismo , Lipólise , Preparações Farmacêuticas/metabolismo , Estômago/enzimologia , Triglicerídeos/metabolismo , Animais , Química Farmacêutica/métodos , Química Farmacêutica/normas , Digestão , Cães , Concentração de Íons de Hidrogênio , Hidrólise , Lipase/química , Pancreatina/química , Pancreatina/metabolismo , Preparações Farmacêuticas/química , Proteínas Recombinantes , Triglicerídeos/químicaRESUMO
PURPOSE: To develop a minimally-invasive method for direct visualization of drug delivery systems in the human stomach and to compare the obtained results with an established in vitro model. The method should provide the capsule rupture, dispersion characteristics, and knowledge regarding the surrounding physiological environment in the stomach. METHODS: A capsule endoscopic method was developed. The disintegration time, dispersion characteristics and the impact of the physiological environment on different lipid based delivery systems in different gelatin capsules in the fasted stomach of nine healthy volunteers were visualized. Biorelevant dissolution studies using a USP II apparatus and a droplet size analysis of the released SNEDDS were performed. RESULTS: Visualization of the behavior of both hard and soft gelatin capsules formulations was possible. The disintegration and dispersion of EP oil in a soft capsule and SNEDDS in a hard shell capsule were visualized. The in vitro release rates were different from the in vivo release rates of the soft capsule due to volume, fluid composition and motility differences but not for the hard capsule containing SNEDDS. CONCLUSIONS: A minimally-invasive capsule endoscopic method was developed for direct visualizing of drug delivery systems in the human stomach and maybe later, in the duodenum.
Assuntos
Endoscopia por Cápsula/métodos , Sistemas de Liberação de Medicamentos/métodos , Jejum/metabolismo , Ácidos Linoleicos/metabolismo , Óleos de Plantas/metabolismo , Trato Gastrointestinal Superior/metabolismo , Ácido gama-Linolênico/metabolismo , Administração Oral , Adulto , Cápsulas , Estudos de Viabilidade , Feminino , Humanos , Ácidos Linoleicos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Oenothera biennis , Óleos de Plantas/administração & dosagem , Trato Gastrointestinal Superior/efeitos dos fármacos , Adulto Jovem , Ácido gama-Linolênico/administração & dosagemRESUMO
PURPOSE: To investigate the in vitro release and degradation of desmopressin from saturated triglyceride microparticles under both lipolytic and proteolytic conditions. METHODS: The release of desmopressin from different solid lipid microparticles in the absence and presence of a microbial lipase and protease was determined. Trilaurin (TG12), trimyristin (TG14), tripalmitin (TG16), and tristearin (TG18) were used as lipid excipients to produce solid lipid microparticles. RESULTS: In the presence of lipase, the rate of drug release from different lipid particles was in the order of TG14 > TG16 > TG18, which is the same rank order as the lipid degradation rate. A reverse rank order was found for the protection of desmopressin from enzymatic degradation due to spatial separation of desmopressin from the protease. TG12 accelerated the release of desmopressin from all lipid particles when added as either drug-free microparticles to the lipolysis medium or incorporated in TG16 particles. Additionally, TG12 particles protected desmopressin from degradation when present in the lipolysis medium with the other lipid microparticles. CONCLUSIONS: TG12 is a very interesting lipid for oral lipid formulations containing peptides and proteins as it alters release and degradation of the incorporated desmopressin. The present study demonstrates the possibility of bio-relevant in vitro evaluation of lipid-based solid particles.
Assuntos
Antidiuréticos/administração & dosagem , Desamino Arginina Vasopressina/administração & dosagem , Excipientes/metabolismo , Lipólise , Proteólise , Triglicerídeos/metabolismo , Animais , Antidiuréticos/metabolismo , Ascomicetos/enzimologia , Bovinos , Desamino Arginina Vasopressina/metabolismo , Lipase/metabolismoRESUMO
Until relatively recently, the pediatric population has largely been ignored during the development of new drug products, which has led to a high level of "off-label" use of drugs in this particular population. In this study, an infant friendly self-nanoemulsifying drug delivery system (SNEDDS) was developed for oral delivery of a commonly used "off-label" drug - amphotericin B (AmB). AmB was complexed with monoacyl-phosphatidylcholine (MAPC) by lyophilization, transforming crystalline AmB into its amorphous state in the AmB-MAPC complex (APC). The APC-loaded SNEDDS (APC-SNEDDS) showed excellent self-emulsifying properties; after dispersion of the APC-SNEDDS in purified water, nanoscale emulsion droplets were formed within 1 min with a z-average size of 179 ± 1 nm. In vitro pediatric gastrointestinal (GI) digestion and dissolution results showed that the APC-SNEDDS significantly increased the amount of AmB solubilized in aqueous phase and that the precipitated AmB from the APC-SNEDDS re-dissolved faster, compared with crystalline AmB in SNEDDS (AmB-SNEDDS), the complex without the SNEDDS (APC), the physical mixture of AmB and MAPC (AmB/MAPC PM), and crystalline AmB alone (AmB). Overall, the present in vitro results suggest that integrating the APC into an infant friendly SNEDDS is a promising approach for oral delivery of AmB to young pediatric patients.
Assuntos
Anfotericina B , Sistemas de Liberação de Medicamentos , Emulsões , Fosfatidilcolinas , Anfotericina B/administração & dosagem , Anfotericina B/química , Anfotericina B/farmacocinética , Fosfatidilcolinas/química , Administração Oral , Humanos , Lactente , Solubilidade , Antifúngicos/administração & dosagem , Antifúngicos/química , Antifúngicos/farmacocinética , Tamanho da Partícula , Nanopartículas/química , Liberação Controlada de FármacosRESUMO
Current treatment strategies are moving towards patient-centricity, which emphasizes the need for new solutions allowing for medication tailored to a patient. This can be realized by precision medicine where patient diversity is considered during treatment. However, the broader use of precision medicine is restricted by the current technological solutions and rigid manufacturing of pharmaceutical products by mass production principles. Additive manufacturing of pharmaceutical products can provide a feasible solution to this challenge. In this review, a particular subtype of additive manufacturing, that is, binder jetting 3D printing, is introduced as a solution for fabricating pharmaceutical solid products that can be considered as precision medicine. Technical aspects, practical applications, unique advantages and challenges related to this technique are discussed, indicating that binder jetting 3D printing possesses the potential for fabricating already new product prototypes, where diversity in patient treatment in terms of the needs for specific drug type, dose and drug release can be accounted. To further advance this type of mass customization of pharmaceuticals, multidisciplinary research initiatives are needed not only to cover the engineering aspects but also to bridge these innovations with patient-centric perspectives.