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1.
Eur J Pharm Sci ; 202: 106880, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39181171

RESUMEN

High-shear (HS) melt granulation and hot melt extrusion (HME) were compared as perspective melt-based technologies for preparation of amorphous solid dispersions (ASDs). ASDs were prepared using mesoporous carriers (SyloidⓇ 244FP or NeusilinⓇ US2), which were loaded with carvedilol dispersed in polymeric matrix (polyethylene glycol 6000 or SoluplusⓇ). Formulations with high carvedilol content were obtained either by HME (11 extrudates with polymer:carrier ratio 1:1) or HS granulation (6 granulates with polymer:carrier ratio 3:1). DSC and XRD analysis confirmed the absence of crystalline carvedilol for the majority of prepared ADSs, thus confirming the stabilizing effect of selected polymers and carriers over amorphous carvedilol. HME produced larger particles compared to HS melt granulation, which was in line with better flow time and Carr index of extrudates. Moreover, SEM images revealed smoother surface of ASDs obtained by HME, contributing to less obstructed flow. The rougher and more porous surface of HS granules was correlated to larger granule specific surface area, manifesting in faster carvedilol release from SyloidⓇ 244FP-based granules, as compared to their HME counterparts. Regarding dissolution, the two HS-formulations performed superior to pure crystalline carvedilol, thereby confirming the suitability of HS melt granulation for developing dosage forms with improved carvedilol dissolution.


Asunto(s)
Carvedilol , Portadores de Fármacos , Liberación de Fármacos , Polietilenglicoles , Solubilidad , Carvedilol/química , Carvedilol/administración & dosificación , Portadores de Fármacos/química , Porosidad , Polietilenglicoles/química , Tecnología de Extrusión de Fusión en Caliente/métodos , Composición de Medicamentos/métodos , Polivinilos
2.
Int J Pharm ; 664: 124626, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39208952

RESUMEN

The manufacturing of tablets containing biologics exposes the biologics to thermal and shear stresses, which are likely to induce structural changes (e.g., aggregation and denaturation), leading to the loss of their activity. Saccharides often act as stabilizers of proteins in formulations, yet their stabilizing ability throughout solid oral dosage processing, such as tableting, has been barely studied. This work aimed to investigate the effects of formulation and process (tableting and spray-drying) variables on catalase tablets containing dextran, mannitol, and trehalose as potential stabilizers. Non-spray-dried and spray-dried formulations were prepared and tableted (100, 200, and 400 MPa). The enzymatic activity, number of aggregates, reflecting protein aggregation and structure modifications were studied. A principal component analysis was performed to reveal underlying correlations. It was found that tableting and spray-drying had a notable negative effect on the activity and number of aggregates formed in catalase formulations. Overall, dextran and mannitol failed to preserve the catalase activity in any unit operation studied. On the other hand, trehalose was found to preserve the activity during spray-drying but not necessarily during tableting. The study demonstrated that formulation and process variables must be considered and optimized together to preserve the characteristics of catalase throughout processing.


Asunto(s)
Catalasa , Dextranos , Composición de Medicamentos , Excipientes , Manitol , Comprimidos , Trehalosa , Catalasa/química , Trehalosa/química , Manitol/química , Dextranos/química , Excipientes/química , Composición de Medicamentos/métodos , Química Farmacéutica/métodos , Secado por Pulverización , Agregado de Proteínas
3.
Front Bioeng Biotechnol ; 11: 1270364, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781530

RESUMEN

Over the past several decades, there has been significant growth in the design and development of more efficient and advanced biomaterials based on non-cellulosic biological macromolecules. In this context, hydrogels based on stimuli-responsive non-cellulosic biological macromolecules have garnered significant attention because of their intrinsic physicochemical properties, biological characteristics, and sustainability. Due to their capacity to adapt to physiological pHs with rapid and reversible changes, several researchers have investigated pH-responsive-based non-cellulosic polymers from various materials. pH-responsive hydrogels release therapeutic substances in response to pH changes, providing tailored administration, fewer side effects, and improved treatment efficacy while reducing tissue damage. Because of these qualities, they have been shown to be useful in a wide variety of applications, including the administration of chemotherapeutic drugs, biological material, and natural components. The pH-sensitive biopolymers that are utilized most frequently include chitosan, alginate, hyaluronic acid, guar gum, and dextran. In this review article, the emphasis is placed on pH stimuli-responsive materials that are based on biological macromolecules for the purposes of drug administration.

4.
J Control Release ; 362: 381-395, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37579977

RESUMEN

This review highlights the importance of controlling the digestion process of orally administered lipid-based delivery systems (LBDS) and their performance. Oral LBDS are prone to digestion via pancreatic lipase in the small intestine. Rapid or uncontrolled digestion may cause the loss of delivery system integrity, its structural changes, reduced solubilization capacity and physical stability issues. All these events can lead to uncontrolled drug release from the digested LBDS into the gastrointestinal environment, exposing the incorporated drug to precipitation or degradation by luminal proteases. To prevent this, the digestion rate of orally administered LBDS can be estimated by appropriate choice of the formulation type, excipient combinations and their ratios. In addition, in vitro digestion models like pH-stat are useful tools to evaluate the formulation digestion rate. Controlling digestion can be achieved by conventional lipase inhibitors like orlistat, sterically hindering of lipase adsorption on the delivery system surface with polyethylene glycol (PEG) chains, lipase desorption or saturation of the interface with surfactants as well as formulating LBDS with ester-free excipients. Recent in vivo studies demonstrated that digestion inhibition lead to altered pharmacokinetic profiles, where Cmax and Tmax were reduced in spite of same AUC compared to control or even improved oral bioavailability.

5.
Int J Pharm ; 642: 123097, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37268028

RESUMEN

Continuous manufacturing of oral solids is a complex process in which critical material attributes (CMAs), formulation and critical process parameters (CPPs) play a fundamental role. However, assessing their effect on the intermediate and final product's critical quality attributes (CQAs) remains challenging. The aim of this study was to tackle this shortcoming by evaluating the influence of raw material properties and formulation composition on the processability and quality of granules and tablets on a continuous manufacturing line. Powder-to-tablet manufacturing was performed using four formulations in various process settings. Pre-blends of different drug loadings (2.5 % w/w and 25% w/w) and two BCS classes (Class I and II) were continuously processed on an integrated process line ConsiGmaTM 25, including twin screw wet granulation, fluid bed drying, milling, sieving, in-line lubrication and tableting. The liquid-to-solid ratio and the granule drying time were varied to process granules under nominal, dry and wet conditions. It was shown that the BCS class and the drug dosage influenced the processability. Intermediate quality attributes, such as the loss on drying and the particle size distribution, directly correlated with the raw material's properties and process parameters. Process settings had a profound impact on the tablet's hardness, disintegration time, wettability and porosity.


Asunto(s)
Excipientes , Tecnología Farmacéutica , Composición de Medicamentos , Tamaño de la Partícula , Humectabilidad , Comprimidos
6.
Pharmaceutics ; 14(12)2022 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-36559111

RESUMEN

The aim of this study was to develop a continuous pilot-scale solidification and characterization of self-emulsifying drug delivery systems (SEDDSs) via hot melt extrusion (HME) using Soluplus® and Kollidon® VA-64. First, an oil-binding capacity study was performed to estimate the maximal amount of SEDDSs that the polymers could bind. Then, HME was conducted using a Coperion 18 mm ZSK18 pilot plant-scale extruder with split-feeding of polymer and SEDDS in 10, 20, and 30% w/w SEDDSs was conducted. The prepared extrudates were characterized depending on appearance, differential scanning calorimetry, wide-angle X-ray scattering, emulsification time, droplet size, polydispersity index, and cloud point. The oil-binding studies showed that the polymers were able to bind up to 50% w/w of liquid SEDDSs. The polymers were processed via HME in a temperature range between 110 and 160 °C, where a plasticizing effect of the SEDDSs was observed. The extrudates were found to be stable in the amorphous state and self-emulsified in demineralized water at 37 °C with mean droplet sizes between 50 and 300 nm. A cloud point and phase inversion were evident in the Soluplus® samples. In conclusion, processing SEDDSs with HME could be considered a promising alternative to the established solidification techniques as well as classic amorphous solid dispersions for drug delivery.

7.
Expert Opin Drug Deliv ; 19(9): 1013-1032, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35943158

RESUMEN

INTRODUCTION: Self-emulsifying drug delivery systems (SEDDS) are a promising strategy to improve the oral bioavailability of poorly water-soluble drugs (PWSD). However, poor drug loading capacity and formulation instability are the main setbacks of traditional SEDDS. The use of polymeric precipitation inhibitors was shown to create supersaturable SEDDS with increased drug loads, and their solidification can help to overcome the instability challenge. As an alternative to several existing SEDDS solidification technologies, hot melt extrusion (HME) has the potential for lean and continuous manufacturing of supersaturable solid-SEDDS. Despite being ubiquitously applied in solid lipid and polymeric processing, HME has not yet been widely considered for the preparation of SEDDS. AREAS COVERED: The review begins why SEDDS as the preferred lipid-based delivery systems (LBDS) is suitable for the oral delivery of PWSD and discusses the common barriers to oral administration. The potential of LBDS to surmount them is discussed. SEDDS as the flagship of LBDS for PWSD is proposed with a special emphasis on solid-SEDDS. Finally, the opportunities and challenges of HME from the lipid-based excipient (LBE) processing and product performance standpoint are highlighted. EXPERT OPINION: HME is a continuous, solvent-free, cost-effective, and scalable technology for manufacturing solid supersaturable SEDDS. Several critical formulations and process parameters for successfully preparing SEDDS via HME are identified.


Asunto(s)
Excipientes , Tecnología de Extrusión de Fusión en Caliente , Sistemas de Liberación de Medicamentos , Emulsiones , Lípidos , Preparaciones Farmacéuticas , Polímeros , Solubilidad , Agua
8.
Drug Dev Ind Pharm ; 43(10): 1694-1702, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28589736

RESUMEN

AIM: In this study, self-emulsifying drug delivery system (SEDDS) for oral delivery of opioid peptide dalargin were developed and characterized in vitro. METHODS: Dalargin lipophilicity was increased by O-esterification of tyrosine OH group, hydrophobic ion pairing, or a combination thereof. Distribution coefficients (log D) of lipidized dalargin derivatives were determined. Then, dalargin was incorporated in chosen SEDDS, namely SEDDS-1, composed of 50% Capmul 907, 40% Cremophor EL, and 10% propylene glycol and comparatively more lipophilic SEDDS-2 composed of 30% Captex 8000, 30% Capmul MCM, 30% Cremophor EL, and 10% propylene glycol. Additionally, SEDDS were characterized regarding droplet size, polydispersity index (PDI), cloudy point, physical stability and stability against pancreatic lipase. Furthermore, mucus permeating properties of SEDDS and their ability to protect the incorporated dalargin against proteolysis by trypsin, α-chymotrypsin, elastase, simulated gastric fluid (SGF), and simulated intestinal fluid (SIF) were evaluated. RESULTS: The highest dalargin drug payload of 4.57% in SEDDS-2 was achieved when dalargin palmitate (pDAL) was ion paired with sodium dodecyl sulfate (SDS) in molar ratio 1:1. Moreover, SEDDS-1 and SEDDS-2 had a narrow droplet size distribution with average droplet sizes of 42.1 and 33.1 nm with PDI of 0.042 and 0.034, respectively. Lipolysis study showed that within 30 min 78.5% of SEDDS-1 and 92.1% of SEDDS-2 were digested. In addition, both SEDDS exhibited mucus permeating properties as well as a protective effect against enzymatic degradation by trypsin, α-chymotrypsin, elastase, SGF and SIF. CONCLUSION: The results of this study suggest that the developed SEDDS could be considered for oral opioid peptide delivery.


Asunto(s)
Caprilatos/química , Quimotripsina/química , Sistemas de Liberación de Medicamentos/métodos , Emulsiones/química , Glicéridos/química , Lípidos/química , Moco/química , Péptidos Opioides/química , Polietilenglicoles/química , Propilenglicol/química , Administración Oral , Disponibilidad Biológica , Péptidos Opioides/administración & dosificación , Péptidos Opioides/farmacología , Solubilidad
9.
J Control Release ; 255: 242-257, 2017 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-28457894

RESUMEN

Peptide therapeutics is currently one of the fastest growing markets worldwide and consequently convenient ways of administration for these drugs are highly on demand. In particular, oral dosage forms would be preferred. A relative large molecular weight and high hydrophilicity, however, result in comparatively very low oral bioavailability being in most cases below 1%. Lipid based formulations (LBF), in particular self-emulsifying drug delivery systems (SEDDS) and solid lipid nanoparticles (SLN) as well as liposomes are among the most promising tools for oral peptide delivery. Key to success in orally delivering peptides via LBF seems to be a sufficiently high lipophilic character of those therapeutic agents. Hence, different non-covalent and covalent peptide lipidization methods from drug delivery point of view are presented. On the one hand, among non-covalent lipidization methods hydrophobic ion pairing seems to be a promising way to sufficiently increase peptide lipophilicity providing high drug payloads in the lipid phase, a protective effect against presystemic metabolism via thiol-disulphide exchange reactions and proteolysis as well as an improved intestinal membrane permeability. On the other hand, covalent methods like conjugating fatty acids via amidation, esterification, reversible aqueous lipidization (REAL) and cyclization also show potential. The present review therefore describes those lipidization methods in detail and critically evaluates their contribution in successfully overcoming the oral barriers.


Asunto(s)
Lípidos/química , Péptidos/química , Administración Oral , Animales , Sistemas de Liberación de Medicamentos , Humanos , Absorción Intestinal , Péptidos/administración & dosificación , Péptidos/farmacocinética , Péptidos/uso terapéutico , Proteolisis , Vacunas
10.
Eur J Pharm Sci ; 106: 41-48, 2017 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-28549680

RESUMEN

The aim of this study was to evaluate the impact of in situ cross-linkers on the gelling and mucoadhesive properties of thiomers. Polycarbophil-cysteine conjugate (PCP-cys) was synthesized by covalent attachment of l-cysteine to polycarbophil via amide bond formation mediated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDAC) and N-hydroxysuccinimide (NHS) whereas in situ cross-linkers (PAA-cys-MNA) were synthesized by the same bond formation between poly(acrylic acid) (PAA) of 2.1-, 6-, and 15kDa and 2-((2-amino-2-carboxyethyl)disulfanyl)nicotinic acid (cys-MNA) used as ligand. The in situ cross-linking properties were studied via rheological measurements of dynamic viscosity of mixtures of PCP-cys and PAA-cys-MNA with purified porcine intestinal mucus and via rotating cylinder method. The diffusion of polymers in purified porcine intestinal mucus was studied via rotating tube technique. The results showed that in situ cross-linkers (PAA 2.1-, 6-, 15kDa) increase the dynamic viscosity of PCP-cys/mucus mixtures by 5.1-, 5.6-, and 3.5-fold. Combinations of 10% of in situ cross-linkers PAA 2.1-, 6- or 15kDa and 90% PCP-cys increased the adhesion time 1.1-, 2.0- and 4.9-fold, respectively, compared to PCP-cys alone. Diffusion study showed that low molecular mass PAAs highly penetrate into the mucus gel layer due to their high polymer chain mobility compared to PCP-cys. The results provide evidence for the potential of in situ cross-linking agents as gelling and mucoadhesion enhancers.


Asunto(s)
Resinas Acrílicas/síntesis química , Adhesivos/metabolismo , Reactivos de Enlaces Cruzados/química , Cisteína/química , Mucosa Intestinal/química , Resinas Acrílicas/química , Animales , Carbodiimidas/química , Difusión , Portadores de Fármacos/química , Liberación de Fármacos , Geles/química , Humanos , Mucosa Intestinal/metabolismo , Peso Molecular , Moco/metabolismo , Ácidos Nicotínicos/química , Reología/métodos , Succinimidas/química , Porcinos , Resistencia a la Tracción , Viscosidad
11.
J Pharm Sci ; 106(5): 1322-1330, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28137696

RESUMEN

It was the aim of this study to incorporate a model peptide bivalirudin in self-emulsifying drug delivery system (SEDDS) and compare its storage stability with conventional aqueous solutions. Firstly, bivalirudin lipophilicity was increased via hydrophobic ion pairing using anionic or cationic surfactants. The chosen bivalirudin docusate complex (BIV/AOT) was incorporated into SEDDS composed of 40% (w/w) Cremophor EL, 20% (w/w) Capmul PG-8, and 40% (w/w) propylene glycol with a drug payload of 0.20% (w/w). SEDDS were stable over a wide pH range for at least 7 days at 37°C and showed an immediate bivalirudin release profile. Moreover, aqueous bivalirudin solutions were shown to be most stable between apparent pH 3 and 4. Furthermore, 94.39% and 72.66% of bivalirudin in SEDDS and 10% propylene glycol, respectively, remained intact after 90 days of storage at 25°C ± 2°C, whereas 99.12% and 80.54% were still intact in SEDDS and 10% propylene glycol at 5°C ± 3°C, respectively. Bivalirudin in reconstituted commercially available product Angiomax® was, however, long-term unstable. According to these findings, SEDDS could be considered as a potential bivalirudin stabilization medium against chemical degradation.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Emulsionantes/química , Hirudinas/química , Interacciones Hidrofóbicas e Hidrofílicas , Fragmentos de Péptidos/química , Antitrombinas/química , Antitrombinas/normas , Sistemas de Liberación de Medicamentos/normas , Estabilidad de Medicamentos , Almacenaje de Medicamentos/métodos , Almacenaje de Medicamentos/normas , Emulsionantes/normas , Hirudinas/normas , Fragmentos de Péptidos/normas , Proteínas Recombinantes/química , Proteínas Recombinantes/normas
12.
Int J Pharm ; 519(1-2): 206-212, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-28077295

RESUMEN

This study was aimed to improve the mucoadhesive properties of SNEDDS by the incorporation of acyl chitosan including octanoyl chitosan (OC), lauroyl chitosan (LC) and palmitoyl chitosan (PC). SNEDDS and acyl chitosan SNEDDS were characterized regarding droplet size and zeta potential. Their mucoadhesivity on porcine intestinal mucosa was evaluated by falling liquid film technique using Sudan Red G as marker. Degree of substitution of chitosan was determined to be 52.8%, 64.8 and 48.5% for OC, LC and PC, respectively. SNEDDS and acyl chitosan SNEDDS displayed a droplet size less than 50nm and 80-300nm as well as a zeta potential of -0.2 to -1.6 and 0.05 to 0.99mV, respectively. Introducing 2% acyl chitosan into SNEDDS increased the residence time of SNEDDS on intestinal mucosa 2-fold. It is concluded that due to the incorporation of acyl chitosan into SNEDDS, their mucoadhesive properties can be increased.


Asunto(s)
Adhesivos/administración & dosificación , Adhesivos/química , Quitosano/química , Emulsiones/administración & dosificación , Emulsiones/química , Mucosa Intestinal/metabolismo , Nanopartículas/química , Animales , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Porcinos
13.
Eur J Pharm Biopharm ; 109: 113-121, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27693677

RESUMEN

AIM: The aim of this study was to develop SEDDS for oral enoxaparin administration and evaluate it in vitro and in vivo. METHODS: The emulsifying properties of SEDDS composed of long chain lipids (LC-SEDDS), medium chain lipids (MC-SEDDS), short chain lipids (SC-SEDDS) and no lipids (NL-SEDDS) were evaluated. Thereafter, enoxaparin was incorporated via hydrophobic ion pairing in the chosen SEDDS, which were evaluated regarding their mucus permeating properties, stability towards pancreatic lipase, drug release profile and cytotoxicity. Finally, in vivo performance of SEDDS was evaluated. RESULTS: The average droplet size of chosen LC-SEDDS, MC-SEDDS and NL-SEDDS ranged between 30 and 40nm. MC-SEEDS containing 30% Captex 8000, 30% Capmul MCM, 30% Cremophor EL and 10% propylene glycol and NL-SEDDS containing 31.5% Labrafil 1944, 22.5% Capmul PG-8, 9% propylene glycol, 27% Cremophor EL and 10% DMSO exhibited 2-fold higher mucus diffusion than LC-SEDDS and were therefore chosen for further studies. The enoxaparin-dodecylamine complex (ENOX/DOA) was incorporated in a payload of 2% (w/w) into MC-SEDDS and NL-SEDDS. After 90min 97% of MC-SEDDS and 5% of NL-SEDDS were degraded by pancreatic lipase. Both MC-SEDDS and NL-SEDDS showed sustained in vitro enoxaparin release. Furthermore, orally administrated MC-SEDDS and NL-SEDDS yielded an absolute enoxaparin bioavailability of 2.02% and 2.25%, respectively. CONCLUSION: According to the abovementioned findings, SEDDS could be considered as a potential oral LMWH delivery system.


Asunto(s)
Química Farmacéutica/métodos , Sistemas de Liberación de Medicamentos , Emulsionantes/química , Emulsiones/química , Enoxaparina/administración & dosificación , Administración Oral , Aminas/química , Disponibilidad Biológica , Células CACO-2 , Supervivencia Celular , Cromatografía Líquida de Alta Presión , Difusión , Portadores de Fármacos/química , Liberación de Fármacos , Enoxaparina/química , Heparina de Bajo-Peso-Molecular , Humanos , Lípidos/química , Oxazinas/química , Tamaño de la Partícula , Solubilidad , Xantenos/química
14.
Carbohydr Polym ; 152: 632-638, 2016 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-27516313

RESUMEN

AIM: It is the aim of this study to synthesize hyaluronic acid (HA) derivatives bearing mucoadhesive properties and showing prolonged stability at pH 7.4 and under oxidative condition as liquid dosage form. METHODS: HA was modified by thiolation with l-cysteine (HA-SH) and by conjugation with 2-mercaptonicotinic acid-l-cysteine ligand to obtain an S-protected derivative (HA-MNA). The polymers were characterized by determination of thiol group content and mercaptonicotinic acid content. Cytotoxicity, stability and mucoadhesive properties (rheological evaluation and tensile test) of the polymers were evaluated. RESULTS: HA-SH and HA-MNA could be successfully synthesized with a degree of modification of 5% and 9% of the total moles of carboxylic acid groups, respectively. MTT assay revealed no toxicity for the polymers. HA-SH resulted to be unstable both at pH 7.4 and under oxidative conditions, whereas HA-MNA was stable under both conditions. Rheological assessment showed a 52-fold and a 3-fold increase in viscosity for HA-MNA incubated with mucus compared to unmodified HA and HA-SH, respectively. Tensile evaluation carried out with intestinal and conjunctival mucosa confirmed the higher mucoadhesive properties of HA-MNA compared to HA-SH. CONCLUSIONS: According to the presented results, HA-MNA appears to be a potent excipient for the formulation of stable liquid dosage forms showing comparatively high mucodhesive properties.


Asunto(s)
Ácido Hialurónico , Células CACO-2 , Supervivencia Celular , Humanos , Ácido Hialurónico/síntesis química , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Concentración de Iones de Hidrógeno
15.
Int J Pharm ; 508(1-2): 102-8, 2016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27143595

RESUMEN

AIM: The aim of this study is the development of self-emulsifying drug delivery systems (SEDDS) differing in amounts of ester substructures and to evaluate their stability in presence of pancreatic lipase and protective effect against luminal enzymatic metabolism using leuprorelin as model peptide drug. METHODS: Hydrophobic leuprolide oleate was incorporated into three different SEDDS formulations and their stability towards pancreatic lipases was investigated utilizing a dynamic in vitro digestion model. Protective effect of SEDDS in respect to peptide drug stability against proteolytic enzymes, trypsin and α-chymotrypsin, was determined via HPLC. RESULTS: Results of in vitro digestion demonstrated that 80% of SEDDS containing the highest amount of ester linkages was degraded within 60min. In comparison to that, SEDDS without ester bonds showed no degradation. With increasing oil droplets hydrolysis the remaining amount of peptide encapsulated into formulation decreased. Furthermore, after 180min incubation with trypsin up to 33.5% and with α-chymotrypsin up to 60.5% of leuprolide oleate was intact while leuprorelin acetate aqueous solution was completely metabolized by trypsin within 120min and by α-chymotrypsin within 5min. Protective effect in environment containing lipases was lower due to oil phase degradation, however, the amount of peptide in ester-free SEDDS was remarkably higher compared to SEDDS susceptible to lipases. CONCLUSION: The present study revealed that SEDDS stable towards hydrolysis is able to exhibit a protective effect for oral peptide delivery.


Asunto(s)
Quimotripsina/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Emulsiones/química , Intestinos/enzimología , Leuprolida/química , Lipasa/metabolismo , Tripsina/metabolismo , Animales , Composición de Medicamentos/métodos , Liberación de Fármacos , Estabilidad de Medicamentos , Ésteres/metabolismo , Leuprolida/metabolismo , Leuprolida/farmacocinética , Porcinos
16.
Drug Deliv ; 23(6): 2074-83, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26923905

RESUMEN

CONTEXT: Self-emulsifying drug delivery systems (SEDDS) are among most promising tools for improving oral peptide bioavailability. OBJECTIVE: In this study, in vitro protective effect of SEDDS containing desmopressin against presystemic inactivation by glutathione and α-chymotrypsin was evaluated. MATERIALS AND METHODS: The partitioning coefficient (log P) of desmopressin was increased via hydrophobic ion pairing using anionic surfactants. Solubility studies were performed to select the appropriate solvents for SEDDS preparation. Subsequently, droplet size and emulsification properties of 22 SEDDS formulations were evaluated. Moreover, the peptide-surfactant complex was dissolved in two chosen SEDDS formulations. Finally, SEDDS containing desmopressin were characterized regarding lipase stability, toxicity, and in vitro protective effect toward glutathione and α-chymotrypsin. RESULTS: Desmopressin log P was increased from initial -6.13 to 0.33 using sodium docusate. The resulting desmopressin docusate complex (DES/AOT) was incorporated in two different SEDDS formulations, containing Capmul 907 P as main solvent. DES/AOT-SEDDS-F4 (containing 0.07% w/w DES/AOT) was composed of 50% Capmul 907P, 40% Cremophor RH40, and 10% Transcutol. The comparatively more hydrophilic formulation DES/AOT-SEDDS-F15 (containing 0.25% w/w DES/AOT) consisted of 20% Capmul 907P, 40% Acconon MC8-2, and 40% Tween 20. Both formulations were stable toward digestion by lipase and protected desmopressin toward α-chymotrypsin degradation. Moreover, DES/AOT-SEDDS-F4 also protected the peptide from thiol/disulfide exchange reactions with glutathione and was not cytotoxic at a concentration of 0.375% (w/w). CONCLUSION: DES/AOT-SEDDS-F4 protected desmopressin from in vitro glutathione and α-chymotrypsin degradation. DES/AOT-SEDDS-F4 was metabolically stable and nontoxic. Therefore, it could be considered as a potential delivery system for oral desmopressin administration.


Asunto(s)
Quimotripsina/química , Emulsionantes/química , Glutatión/química , Polietilenglicoles/química , Polisorbatos/química , Administración Oral , Disponibilidad Biológica , Química Farmacéutica , Quimotripsina/metabolismo , Sistemas de Liberación de Medicamentos , Emulsionantes/metabolismo , Emulsionantes/farmacocinética , Glutatión/metabolismo , Humanos , Solubilidad , Solventes/química
17.
Expert Opin Drug Deliv ; 13(7): 923-9, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27020604

RESUMEN

OBJECTIVES: To develop a self nano-emulsifying delivery system (SNEDS) for model peptide lanreotide providing a protective effect towards thiol-disulfide exchange reactions. METHODS: Ion-paired complexes of lanreotide with surfactants were prepared. In the following, Log P (octanol/water) of these complexes was determined. Lanreotide-loaded SNEDS (Lan/Deo-SN2 and Lan/Deo-SN3) were characterized for payload, droplet size and zeta potential. Lan/Deo-SN2 and Lan/Deo-SN3 were incubated with reduced glutathione (GSH) and thiol-enriched casein peptones for the assessment of thiol-disulfide exchange reactions. Ultra-centrifugation was used for separation of lanreotide released from SNEDS. RESULTS: A maximum payload of 6.4% was achieved for Lan/Deo-SN2. Mean droplet size of Lan/Deo-SN2 and Lan/Deo-SN3 was 45 ± 0.20 nm and 37 ± 0.02 nm, respectively. Both formulations showed significant protection towards thiol-disulfide exchange reactions. After 3 h of incubation with GSH, 48% and 80% of lanreotide remained intact when incorporated in Lan/Deo-SN2 and Lan/Deo-SN3, respectively. Furthermore, Lan/Deo-SN2 and Lan/Deo-SN3 showed 47% and 51% protection against thiol enriched casein peptones, respectively. Both formulations showed sustained lanreotide release over a period of 3 h. CONCLUSION: Owing to the results, the above-mentioned approach might be a useful tool to overcome the sulfhydryl barrier of the GI-tract.


Asunto(s)
Péptidos Cíclicos/administración & dosificación , Péptidos/administración & dosificación , Somatostatina/análogos & derivados , Tensoactivos/química , Disulfuros/química , Emulsiones , Glutatión/química , Humanos , Oxidación-Reducción , Péptidos/química , Péptidos Cíclicos/química , Somatostatina/administración & dosificación , Somatostatina/química , Compuestos de Sulfhidrilo/química
18.
Eur J Pharm Sci ; 81: 129-36, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26485536

RESUMEN

It was the aim of this study to develop an oral self-emulsifying drug delivery system (SEDDS) for the peptide drug daptomycin exhibiting an anionic net charge. Drug lipophilicity was increased by hydrophobic ion pairing with cationic surfactant dodecylamine hydrochloride in molar ratio of surfactant to peptide 5:1. Log P (octanol/water) of -5.0 was even raised to +4.8 due to complexation with dodecylamine hydrochloride. Various SEDDS formulations were developed and characterised regarding emulsification properties, droplet size, polydispersity index and zeta potential. When the daptomycin dodecylamine complex (DAP/DOA) was dissolved in a formulation containing 35% Dermofeel MCT, 30% Capmul MCM and 35% Cremophor RH40, a maximum payload of even 8.0% (w/w) corresponding to 5.5% pure daptomycin was achieved. The formulation was degraded by lipase within 90min. Release studies of daptomycin from this formulation emulsified in 50mM phosphate buffer pH6.8 demonstrated a sustained drug release for at least six hours. Moreover, SEDDS exhibited also mucus permeating properties as well as a protective effect towards drug degradation by α-chymotrypsin. According to these results, SEDDS containing 8% DAP/DOA complex may be considered as a new potential oral delivery system for daptomycin.


Asunto(s)
Aminas/química , Antibacterianos/química , Daptomicina/química , Sistemas de Liberación de Medicamentos , 1-Octanol/química , Administración Oral , Aminas/metabolismo , Animales , Antibacterianos/metabolismo , Quimotripsina/química , Daptomicina/metabolismo , Liberación de Fármacos , Emulsiones , Absorción Intestinal , Mucosa Intestinal/metabolismo , Lipasa/química , Permeabilidad , Porcinos , Agua/química
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