scholarly journals Models and methods to characterise levonorgestrel release from intradermally administered contraceptives

2021 ◽  
Author(s):  
Adnan Al Dalaty ◽  
Benedetta Gualeni ◽  
Sion A. Coulman ◽  
James C. Birchall
Keyword(s):  
Ex Vivo ◽  
Extraction Procedure ◽  
In Vitro Release ◽  
Reversed Phase ◽  
Experimental Models ◽  
Detection Methods ◽  
Hormonal Contraceptives ◽  
Limit Of Quantification ◽  
Long Acting

AbstractMicroneedle (MN)-based technologies have been proposed as a means to facilitate minimally invasive sustained delivery of long-acting hormonal contraceptives into the skin. Intradermal administration is a new route of delivery for these contraceptives and therefore no established laboratory methods or experimental models are available to predict dermal drug release and pharmacokinetics from candidate MN formulations. This study evaluates an in vitro release (IVR) medium and a medium supplemented with ex vivo human skin homogenate (SH) as potential laboratory models to investigate the dermal release characteristics of one such hormonal contraceptive that is being tested for MN delivery, levonorgestrel (LNG), and provides details of an accompanying novel two-step liquid–liquid drug extraction procedure and sensitive reversed-phase HPLC–UV assay. The extraction efficiency of LNG was 91.7 ± 3.06% from IVR medium and 84.6 ± 1.6% from the medium supplemented with SH. The HPLC–UV methodology had a limit of quantification of 0.005 µg/mL and linearity between 0.005 and 25 µg/mL. Extraction and detection methods for LNG were exemplified in both models using the well-characterised, commercially available sustained-release implant (Jadelle®). Sustained LNG release from the implant was detected in both media over 28 days. This study reports for the first time the use of biologically relevant release models and a rapid, reliable and sensitive methodology to determine release characteristics of LNG from intradermally administered long-acting drug delivery systems. Graphical abstract

Biochemical and Pharmacological Properties of SANORG 34006, a Potent and Long-Acting Synthetic Pentasaccharide

Blood ◽  
1998 ◽  
Vol 91 (11) ◽  
pp. 4197-4205 ◽  
Author(s):  
J.M. Herbert ◽  
J.P. Hérault ◽  
A. Bernat ◽  
R.G.M. van Amsterdam ◽  
J.C. Lormeau ◽  
...  
Keyword(s):  
Thrombin Generation ◽  
Ex Vivo ◽  
Thrombus Formation ◽  
Factor Xa ◽  
Therapeutic Index ◽  
Inhibitory Effect ◽  
Experimental Models ◽  
Treatment And Prevention ◽  
Long Acting

Abstract SANORG 34006 is a new sulfated pentasaccharide obtained by chemical synthesis. It is an analog of the “synthetic pentasaccharide” (SR 90107/ ORG 31540) which represents the antithrombin (AT) binding site of heparin. SANORG 34006 showed a higher affinity to human AT than SR 90107/ORG 31540 (kd = 1.4 ± 0.3 v 48 ± 11 nmol/L), and it is a potent and selective catalyst of the inhibitory effect of AT on factor Xa (1,240 ± 15 anti–factor Xa U/mg v850 ± 27 anti-factor Xa U/mg for SR 90107/ORG 31540). In vitro, SANORG 34006 inhibited thrombin generation occurring via both the extrinsic and intrinsic pathway. After intravenous (IV) or subcutaneous (SC) administration to rabbits, SANORG 34006 displayed a long-lasting anti–factor Xa activity and inhibition of thrombin generation (TG) ex vivo. SANORG 34006 was slowly eliminated after IV or SC administration to rats, rabbits, and baboons, showed exceptionally long half-lives (between 9.2 hours in rats and 61.9 hours in baboons), and revealed an SC bioavailability near 100%. SANORG 34006 displayed antithrombotic activity by virtue of its potentiation of the anti–factor Xa activity of AT. It strongly inhibited thrombus formation in experimental models of thromboplastin/stasis-induced venous thrombosis in rats (IV) and rabbits (SC) (ED50values = 40.0 ± 3.4 and 105.0 ± 9.4 nmol/kg, respectively). The duration of its antithrombotic effects closely paralleled the ex vivo anti–factor Xa activity. SANORG 34006 enhanced rt-PA–induced thrombolysis and inhibited accretion of125I-fibrinogen onto a preformed thrombus in the rabbit jugular vein suggesting that concomitant use of SANORG 34006 during rt-PA therapy might be helpful in facilitating thrombolysis and preventing fibrin accretion onto the thrombus under lysis. Contrary to standard heparin, SANORG 34006 did not enhance bleeding in a rabbit ear incision model at a dose that equals 10 times the antithrombotic ED50 in this species and, therefore, exhibited a favorable therapeutic index. We suggest that SANORG 34006 is a promising compound in the treatment and prevention of various thrombotic diseases.

Biochemical and Pharmacological Properties of SANORG 34006, a Potent and Long-Acting Synthetic Pentasaccharide

Blood ◽  
1998 ◽  
Vol 91 (11) ◽  
pp. 4197-4205 ◽  
Author(s):  
J.M. Herbert ◽  
J.P. Hérault ◽  
A. Bernat ◽  
R.G.M. van Amsterdam ◽  
J.C. Lormeau ◽  
...  
Keyword(s):  
Thrombin Generation ◽  
Ex Vivo ◽  
Thrombus Formation ◽  
Factor Xa ◽  
Therapeutic Index ◽  
Inhibitory Effect ◽  
Experimental Models ◽  
Treatment And Prevention ◽  
Long Acting

SANORG 34006 is a new sulfated pentasaccharide obtained by chemical synthesis. It is an analog of the “synthetic pentasaccharide” (SR 90107/ ORG 31540) which represents the antithrombin (AT) binding site of heparin. SANORG 34006 showed a higher affinity to human AT than SR 90107/ORG 31540 (kd = 1.4 ± 0.3 v 48 ± 11 nmol/L), and it is a potent and selective catalyst of the inhibitory effect of AT on factor Xa (1,240 ± 15 anti–factor Xa U/mg v850 ± 27 anti-factor Xa U/mg for SR 90107/ORG 31540). In vitro, SANORG 34006 inhibited thrombin generation occurring via both the extrinsic and intrinsic pathway. After intravenous (IV) or subcutaneous (SC) administration to rabbits, SANORG 34006 displayed a long-lasting anti–factor Xa activity and inhibition of thrombin generation (TG) ex vivo. SANORG 34006 was slowly eliminated after IV or SC administration to rats, rabbits, and baboons, showed exceptionally long half-lives (between 9.2 hours in rats and 61.9 hours in baboons), and revealed an SC bioavailability near 100%. SANORG 34006 displayed antithrombotic activity by virtue of its potentiation of the anti–factor Xa activity of AT. It strongly inhibited thrombus formation in experimental models of thromboplastin/stasis-induced venous thrombosis in rats (IV) and rabbits (SC) (ED50values = 40.0 ± 3.4 and 105.0 ± 9.4 nmol/kg, respectively). The duration of its antithrombotic effects closely paralleled the ex vivo anti–factor Xa activity. SANORG 34006 enhanced rt-PA–induced thrombolysis and inhibited accretion of125I-fibrinogen onto a preformed thrombus in the rabbit jugular vein suggesting that concomitant use of SANORG 34006 during rt-PA therapy might be helpful in facilitating thrombolysis and preventing fibrin accretion onto the thrombus under lysis. Contrary to standard heparin, SANORG 34006 did not enhance bleeding in a rabbit ear incision model at a dose that equals 10 times the antithrombotic ED50 in this species and, therefore, exhibited a favorable therapeutic index. We suggest that SANORG 34006 is a promising compound in the treatment and prevention of various thrombotic diseases.

Design and Evaluation of Long Acting Biodegradable PLGA Microspheres for Ocular Drug Delivery

2019 ◽  
Vol 10 ◽  
Author(s):  
Anjali Pandya ◽  
Rajani Athawale ◽  
Durga Puro ◽  
Geeta Bhagwat
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Degradation Products ◽  
Ex Vivo ◽  
Research Work ◽  
Entrapment Efficiency ◽  
Rational Approach ◽  
Plga Microspheres ◽  
Long Acting

Background: The research work involves development of PLGA biodegradable microspheres loaded with dexamethasome for intraocular delivery. Objective: To design and evaluate long acting PLGA microspheres for ocular delivery of dexamethasone. Method: Present formulation involves the development of long acting dexamethasone loaded microspheres composed of a biodegradable controlled release polymer, Poly(D, L- lactide-co-glycolide) (PLGA), for the treatment of posterior segment eye disorders intravitreally. PLGA with monomer ratio of 50:50 of lactic acid to glycolic acid was used to achieve a drug release up to 45 days. Quality by Design approach was utilized for designing the experiments. Single emulsion solvent evaporation technique along with high pressure homogenization was used to facilitate formation of microspheres. Results: Particle size evaluation, drug content and drug entrapment efficiency were determined for the microspheres. Particle size and morphology was observed using Field Emission Gun-Scanning Electron Microscopy (FEG-SEM) and microspheres were in the size range of 1-5 μm. Assessment of drug release was done using in vitro studies and transretinal permeation was observed by ex vivo studies using goat retinal tissues. Conclusion: Considering the dire need for prolonged therapeutic effect in diseases of the posterior eye, an intravitreal long acting formulation was designed. Use of biodegradable polymer with biocompatible degradation products was a rational approach to achieve this aim. Outcome from present research shows that developed microspheres would provide a long acting drug profile and reduce the frequency of administration thereby improving patient compliance.

scholarly journals Ocular Toxoplasmosis: Mechanisms of Retinal Infection and Experimental Models

Parasitologia ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 50-60
Author(s):  
Veronica Rodriguez Fernandez ◽  
Giovanni Casini ◽  
Fabrizio Bruschi
Keyword(s):  
Ex Vivo ◽  
Cell Damage ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Treatment Strategies ◽  
Experimental Models ◽  
Ocular Toxoplasmosis ◽  
Cell Infection

Ocular toxoplasmosis (OT) is caused by the parasite Toxoplasma gondii and affects many individuals throughout the world. Infection may occur through congenital or acquired routes. The parasites enter the blood circulation and reach both the retina and the retinal pigment epithelium, where they may cause cell damage and cell death. Different routes of access are used by T. gondii to reach the retina through the retinal endothelium: by transmission inside leukocytes, as free parasites through a paracellular route, or after endothelial cell infection. A main feature of OT is the induction of an important inflammatory state, and the course of infection has been shown to be influenced by the host immunogenetics. On the other hand, there is evidence that the T. gondii phenotype also has an impact on the distribution of the pathology in different areas. Although considerable knowledge has been acquired on OT, a deeper knowledge of its mechanisms is necessary to provide new, more targeted treatment strategies. In particular, in addition to in vitro and in vivo experimental models, organotypic, ex vivo retinal explants may be useful in this direction.

Sodium alginate nanoparticles as a new transdermal vehicle of glucosamine sulfate for treatment of osteoarthritis

2017 ◽  
Vol 9 (3-4) ◽  
Author(s):  
Asmaa S. El-Houssiny ◽  
Azza A. Ward ◽  
Dina M. Mostafa ◽  
Salwa L. Abd-El-Messieh ◽  
Kamal N. Abdel-Nour ◽  
...  
Keyword(s):  
Side Effects ◽  
Surface Charge ◽  
Ex Vivo ◽  
In Vitro Release ◽  
Glucosamine Sulfate ◽  
Suspension Stability ◽  
Rat Skin ◽  
Release Studies ◽  
Vitro Release

AbstractGlucosamine sulfate (GS) has been used orally for the treatment of osteoarthritis (OA). However, it may be susceptible to the liver first pass phenomenon, which greatly affects its bioavailability, in addition to its side effects on the gastrointestinal tract. Alginate nanoparticles (Alg NPs) were investigated as a new drug carrier for transdermal delivery of GS to improve its effectiveness and reduce side effects. GS-Alg NPs were characterized by encapsulation efficiency, NP yield, particle size and surface charge properties. The in vitro release studies of GS and the ex vivo permeability through rat skin were determined using a UV-Vis spectrophotometer. GS-Alg NPs are within the nanometer range of size. High negative surface charge values are obtained and indicate the high suspension stability of the prepared formulation. The in vitro release studies showed that GS is released from Alg NPs in a sustained and prolonged manner. The ex vivo permeability of GS through rat skin is enhanced significantly after encapsulation in the negatively charged Alg NPs. We successfully reported a highly stable nanoparticlulate system using Alg NPs that permits the encapsulation of GS for topical administration, overcoming the disadvantages of oral administration.

scholarly journals NANO-VESICLES OF SALBUTAMOL SULPHATE IN METERED DOSE INHALERS: FORMULATION, CHARACTERIZATION AND IN VITRO EVALUATION

2017 ◽  
Vol 9 (6) ◽  
pp. 100 ◽  
Author(s):  
Mona G. Arafa ◽  
Bassam M. Ayoub
Keyword(s):  
In Vitro Release ◽  
Pulmonary Delivery ◽  
Entrapment Efficiency ◽  
Reversed Phase ◽  
Molar Ratio ◽  
Metered Dose Inhalers ◽  
Salbutamol Sulphate ◽  
Novel Approach ◽  
Metered Dose

Objective: The present work was aimed to prepare niosomes entrapping salbutamol sulphate (SS) using reversed phase evaporation method (REV).Methods: Niosomes were prepared by mixing span 60 and cholesterol in 1:1 molar ratio in chloroform, SS in water was then added to organic phase to form niosomal SS. Formulations after evaporation of chloroform, freeze centrifuged then lyophilized, were evaluated for particles size, polydispersity index (Pdi), zeta-potential, morphology, entrapment efficiency (EE%) and in vitro release. For pulmonary delivery; metered dose inhalers (MDI) were prepared by suspending SS niosomes equivalent to 20 mg SS in hydrofluoroalkane (HFA). The metered valve was investigated for leakage rate, the total number of puffs/canister, weight/puff, dose uniformity and particle size.Results: The results showed spherical niosomes with 400-451 nm particles that entrapped 66.19% of SS. 76.54±0.132% SS release from niosomes that showed a controlled release profile for 8h. The leakage test was not exceeding 4 mg/3 d, the number of puffs were up to 200puffs/canister, the dose delivered/puff was 0.1 mg and 0.64-4.51μm niosomal aerosol.Conclusion: The results indicate an encouraging strategy to formulate a controlled drug delivery by entrapping (SS) in niosomes which could be packaged into (MDI) that met the requirements of (USP) aerosols guidelines which offering a novel approach to respiratory delivery.

scholarly journals Development of Piperine-Loaded Solid Self-Nanoemulsifying Drug Delivery System: Optimization, In-Vitro, Ex-Vivo, and In-Vivo Evaluation

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2920
Author(s):  
Ameeduzzafar Zafar ◽  
Syed Sarim Imam ◽  
Nabil K. Alruwaili ◽  
Omar Awad Alsaidan ◽  
Mohammed H. Elkomy ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Drug Delivery System ◽  
Delivery System ◽  
Oral Delivery ◽  
Ex Vivo ◽  
In Vitro Release ◽  
System Optimization ◽  
Globule Size

Hypertension is a cardiovascular disease that needs long-term medication. Oral delivery is the most common route for the administration of drugs. The present research is to develop piperine self-nanoemulsifying drug delivery system (PE-SNEDDS) using glyceryl monolinoleate (GML), poloxamer 188, and transcutol HP as oil, surfactant, and co-surfactant, respectively. The formulation was optimized by three-factor, three-level Box-Behnken design. PE-SNEDDs were characterized for globule size, emulsification time, stability, in-vitro release, and ex-vivo intestinal permeation study. The optimized PE-SNEDDS (OF3) showed the globule size of 70.34 ± 3.27 nm, percentage transmittance of 99.02 ± 2.02%, and emulsification time of 53 ± 2 s Finally, the formulation OF3 was transformed into solid PE-SNEDDS (S-PE-SNEDDS) using avicel PH-101 as adsorbent. The reconstituted SOF3 showed a globule size of 73.56 ± 3.54 nm, PDI of 0.35 ± 0.03, and zeta potential of −28.12 ± 2.54 mV. SEM image exhibited the PE-SNEDDS completely adsorbed on avicel. Thermal analysis showed the drug was solubilized in oil, surfactant, and co-surfactant. S-PE-SNEDDS formulation showed a more significant (p < 0.05) release (97.87 ± 4.89% in 1 h) than pure PE (27.87 ± 2.65% in 1 h). It also exhibited better antimicrobial activity against S. aureus and P. aeruginosa and antioxidant activity as compared to PE dispersion. The in vivo activity in rats exhibited better (p < 0.05) antihypertensive activity as well as 4.92-fold higher relative bioavailability than pure PE dispersion. Finally, from the results it can be concluded that S-PE-SNEDDS might be a better approach for the oral delivery to improve the absorption and therapeutic activity.

scholarly journals Optimising experimental research in respiratory diseases: an ERS statement

2018 ◽  
Vol 51 (5) ◽  
pp. 1702133 ◽  
Author(s):  
Philippe Bonniaud ◽  
Aurélie Fabre ◽  
Nelly Frossard ◽  
Christophe Guignabert ◽  
Mark Inman ◽  
...  
Keyword(s):  
Experimental Research ◽  
Task Force ◽  
Ex Vivo ◽  
Experimental Models ◽  
Chronic Obstructive ◽  
Ethical Perspective ◽  
Validity Of Results ◽  
Use Of Resources ◽  
Research Recommendations

Experimental models are critical for the understanding of lung health and disease and are indispensable for drug development. However, the pathogenetic and clinical relevance of the models is often unclear. Further, the use of animals in biomedical research is controversial from an ethical perspective.The objective of this task force was to issue a statement with research recommendations about lung disease models by facilitating in-depth discussions between respiratory scientists, and to provide an overview of the literature on the available models. Focus was put on their specific benefits and limitations. This will result in more efficient use of resources and greater reduction in the numbers of animals employed, thereby enhancing the ethical standards and translational capacity of experimental research.The task force statement addresses general issues of experimental research (ethics, species, sex, age,ex vivoandin vitromodels, gene editing). The statement also includes research recommendations on modelling asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, lung infections, acute lung injury and pulmonary hypertension.The task force stressed the importance of using multiple models to strengthen validity of results, the need to increase the availability of human tissues and the importance of standard operating procedures and data quality.

Nanostructured Lipid Carriers for Intranasal Administration of Olanzapine in the management of Schizophrenia

2021 ◽  
Vol 14 ◽  
Author(s):  
Sarbjot Kaur ◽  
Ujjwal Nautiyal ◽  
Pooja A. Chawla ◽  
Viney Chawla
Keyword(s):  
Drug Delivery ◽  
Ex Vivo ◽  
In Vitro Release ◽  
Nanostructured Lipid Carriers ◽  
Polydispersity Index ◽  
Poloxamer 407 ◽  
Ex Vivo Permeation ◽  
Permeation Studies ◽  
Vitro Release

Background: Background: Olanzapine belongs to a new class of dual spectrum antipsychotic agents. It is known to show promise in managing both the positive and negative symptoms of schizophrenia. Drug delivery systems based on nanostructured lipid carriers (NLC) are expected to provide rapid nose-to-brain transport of this drug and improved distribution into and within the brain. Objective: The present study deals with the preparation and evaluation of olanzapine loaded NLC via the intranasal route for schizophrenia. Methods: Olanzapine-NLC were formulated through the solvent injection method using isopropyl alcohol as the solvent, stearic acid as solid lipid, and oleic acid as liquid lipid, chitosan as a coating agent, and Poloxamer 407 as a surfactant. NLC were characterized for particle size, polydispersity index, entrapment efficiency, pH, viscosity, X-ray diffraction studies, in-vitro mucoadhesion study, in- vitro release and ex-vivo permeation studies. The shape and surface morphology of the prepared NLC was determined through transmission electron microscopy. To detect the interaction of the drug with carriers, compatibility studies were also carried out. Results: Average size and polydispersity index of developed formulation S6 was 227.0±6.3 nm and 0.460 respectively. The encapsulation efficiency of formulation S6 was found to be 87.25 %. The pH, viscosity, in-vitro mucoadhesion study, and in- vitro release of optimized olanzapine loaded NLC were recorded as 5.7 ± 0.05, 78 centipoise, 15±2 min, and 91.96 % respectively. In ex-vivo permeation studies, the percent drug permeated after 210 min was found to be 84.03%. Conclusion: These results reveal potential application of novel olanzapine-NLC in intranasal drug delivery system for treatment of schizophrenia.

scholarly journals Topical Pioglitazone Nanoformulation for the Treatment of Atopic Dermatitis: Design, Characterization and Efficacy in Hairless Mouse Model

Pharmaceutics ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 255 ◽  
Author(s):  
Lupe Carolina Espinoza ◽  
Rodrigo Vera-García ◽  
Marcelle Silva-Abreu ◽  
Òscar Domènech ◽  
Josefa Badia ◽  
...  
Keyword(s):  
Atopic Dermatitis ◽  
Ex Vivo ◽  
In Vitro Release ◽  
Skin Barrier ◽  
Inflammatory Cells ◽  
Hairless Mouse ◽  
Skin Barrier Function ◽  
Inflammatory Parameters ◽  
Therapeutic Benefits

Pioglitazone (PGZ) is a drug used to treat type 2 diabetes mellitus that has been reported to show additional therapeutic activities on diverse inflammatory parameters. The aim of this study was to optimize a topical PGZ-loaded nanoemulsion (PGZ-NE) in order to evaluate its effectiveness for treating atopic dermatitis (AD). The composition of the nanoformulation was established by pseudo-ternary diagram. Parameters such as physical properties, stability, in vitro release profile, and ex vivo permeation were determined. The efficacy study was carried out using oxazolone-induced AD model in hairless mice. PGZ-NE released the drug following a hyperbolic kinetic. Additionally, its properties provided high retention potential of drug inside the skin. Therapeutic benefits of PGZ-NE were confirmed on diverse events of the inflammatory process, such as reduction of lesions, enhancement of skin barrier function, diminished infiltration of inflammatory cells, and expression of pro-inflammatory cytokines. These results were reinforced by atomic force microscope (AFM), which demonstrated the ability of the formulation to revert the rigidification caused by oxazolone and consequently improve the elasticity of the skin. These results suggest that PGZ-NE may be a promising treatment for inflammatory dermatological conditions such as AD.

Sign in / Sign up

Export Citation Format

Share Document