The Experts below are selected from a list of 2148 Experts worldwide ranked by ideXlab platform
Thomas Kissel - One of the best experts on this subject based on the ideXlab platform.
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poly ethylene carbonate as a surface eroding biomaterial for in situ forming Parenteral Drug Delivery systems a feasibility study
European Journal of Pharmaceutics and Biopharmaceutics, 2010Co-Authors: Yu Liu, Annette Kemmer, Klaus Keim, Catherine Curdy, Holger Petersen, Thomas KisselAbstract:To evaluate the technical feasibility of poly(ethylene carbonate), PEC, for injectable in situ forming Drug Delivery systems, the physical properties of PEC solutions were characterized. The solubility of PEC was investigated in different solvents, and the Hildebrand solubility parameters and Flory-Huggins interaction parameters of PEC were determined. By turbidity titration, the experimental ternary phase diagram of water-NMP/DMSO-PEC was constructed. NMP solution required more water to precipitate PEC compared to DMSO solution. The dynamic viscosity of PEC solution increased at lower temperature, higher polymer concentration and longer aging time. Differential scanning calorimetric (DSC) measurements confirmed only weak physical interactions in the system after aging, and the physical aging effect was thermo-reversible. Release of NMP from PEC formulations was twofold slower than that of DMSO at similar concentrations. The morphology of PEC depots after injection into aqueous solution was studied using scanning electron microscopy (SEM). A DMSO formulation of bovine serum albumin displayed less burst release than a NMP formulation. In summary, our investigations demonstrate that in situ depot forming systems can be obtained from PEC solutions. Moreover, a solution of PEC in DMSO would be preferred over NMP due to the reduced burst release.
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in situ forming Parenteral Drug Delivery systems an overview
European Journal of Pharmaceutics and Biopharmaceutics, 2004Co-Authors: C B Packhaeuser, C G Oster, J. Schnieders, Thomas KisselAbstract:Abstract Biodegradable injectable in situ forming Drug Delivery systems represent an attractive alternative to microspheres and implants as Parenteral depot systems. Their importance will grow as numerous proteins will lose their patent protection in the near future. These devices may offer attractive opportunities for protein Delivery and could possibly extend the patent life of protein Drugs. The controlled release of bioactive macromolecules via (semi-) solid in situ forming systems has a number of advantages, such as ease of administration, less complicated fabrication, and less stressful manufacturing conditions for sensitive Drug molecules. For these reasons, a number of polymeric Drug Delivery systems with the ability to form a Drug reservoir at the injection site are under investigation. Here, we review various strategies used for the preparation of in situ forming Parenteral Drug depots and their potential benefits/draw-backs, especially with regard to the Delivery of protein Drug candidates.
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Branched biodegradable polyesters for Parenteral Drug Delivery systems.
Journal of Controlled Release, 2000Co-Authors: Armin Breitenbach, Thomas KisselAbstract:Abstract Continuous, ‘infusion-like’ Drug release profiles from biodegradable Parenteral Delivery systems are difficult to achieve for proteins and other hydrophilic macromolecular Drugs with commonly used linear polyesters from lactic acid (PLA) and its random copolymers with glycolic acid (PLG). Drug release rates can be modified either by increasing the hydrophilicity of polyesters or by manipulating the polymer architecture to adjust polymer degradation rates and thus Drug release. Therefore, we investigated different branching concepts for biodegradable polyesters of PLA and PLG. For one four- and eight-arm poly(ethylene oxide)s (PEO) were grafted with shorter polyester chains leading to star-branched structures. Secondly we obtained comb-like polyesters using both charged and uncharged dextrans or poly(vinyl alcohol)s (PVA) as hydrophilic backbones. The star-shaped and brush-like grafted polymers were intensively characterized by methods, such as NMR, IR, SEC-SLS, DSC and viscosity measurements. Tailor-made properties make these novel biodegradable polyesters promising candidates for Parenteral protein Delivery systems. While the star-branched polyesters have shown some interesting properties with respect to their degradation behavior, retaining the PEO blocks longer than ABA triblock copolymers, their release properties need further optimization. Brush-like branched polyesters on the other hand seem to possess both degradation and release properties meriting further investigations for Parenteral protein Delivery systems.
Yi Shi - One of the best experts on this subject based on the ideXlab platform.
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Recent advances in polymeric microspheres for Parenteral Drug Delivery--part 2.
Expert opinion on drug delivery, 2012Co-Authors: Shirui Mao, Chunqiang Guo, Yi ShiAbstract:Introduction: Currently marketed microsphere products are manufactured with the use of organic solvents which have a negative impact on the environment and stability of biological molecules. With recent advances in fabrication technologies, solvent free methods have demonstrated potential for the preparation of microspheres. Areas covered: New technical advances recently achieved in solvent based microsphere manufacturing processes have allowed for major improvement in product quality and properties. Novel solvent free fabrication methods combined with newly functionalized biodegradable polymers have been explored for their application in the preparation of microspheres containing biological molecules. Expert opinion: Novel fabrication methods for microspheres have been recently reported but technical challenges and development risks remain high for scale up from bench to industrial commercialization. While the applications of microspheres for Delivery of proteins, genes and vaccines have shown promise fo...
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recent advances in polymeric microspheres for Parenteral Drug Delivery part 1
Expert Opinion on Drug Delivery, 2012Co-Authors: Shirui Mao, Chunqiang Guo, Yi ShiAbstract:Introduction: Polymeric microspheres have been established as a valuable Parenteral Drug Delivery system for sustained release of therapeutic agents via subcutaneous or intramuscular injection. Areas covered: Biodegradable polymers which are either synthetic or from natural sources are reviewed with respect to recent advances in exploring their applications for microsphere fabrications. New information on the impact of formulation variables on the properties of microspheres formed by an emulsion method was also presented. The characterization of microspheres using advanced physical analytical techniques was also reviewed and the utilization of the information in assessing in vivo performance of the product was also highlighted. Expert opinion: The broad clinical use of microspheres for Delivery of therapeutic agents in particular biologics such as proteins has not been realized commercially. The limited availability of biodegradable polymers with a long history of regulatory approval and the challenges in...
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Recent advances in polymeric microspheres for Parenteral Drug Delivery – part 1
Expert opinion on drug delivery, 2012Co-Authors: Shirui Mao, Chunqiang Guo, Yi ShiAbstract:Introduction: Polymeric microspheres have been established as a valuable Parenteral Drug Delivery system for sustained release of therapeutic agents via subcutaneous or intramuscular injection. Areas covered: Biodegradable polymers which are either synthetic or from natural sources are reviewed with respect to recent advances in exploring their applications for microsphere fabrications. New information on the impact of formulation variables on the properties of microspheres formed by an emulsion method was also presented. The characterization of microspheres using advanced physical analytical techniques was also reviewed and the utilization of the information in assessing in vivo performance of the product was also highlighted. Expert opinion: The broad clinical use of microspheres for Delivery of therapeutic agents in particular biologics such as proteins has not been realized commercially. The limited availability of biodegradable polymers with a long history of regulatory approval and the challenges in...
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current advances in sustained release systems for Parenteral Drug Delivery
Expert Opinion on Drug Delivery, 2005Co-Authors: Yi Shi, Luk Chiu LiAbstract:Major progresses in the development of Parenteral sustained-release systems have been made in recent years as evidenced by the regulatory approval and market launch of several new products. Both the availability of novel carrier materials and the advances in method of fabrication have contributed to these commercial successes. With the formulation challenges associated with biologics, new Delivery systems have also been evolved specifically to address the unmet needs in the Parenteral sustained release of proteins. In this review paper, different new carriers systems and preparation methods are discussed with special focus on their applications to biologicals.
Nada M. Hoffy - One of the best experts on this subject based on the ideXlab platform.
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Polymer-Free Injectable In Situ Forming Nanovesicles as a New Platform for Controlled Parenteral Drug Delivery Systems
Journal of Pharmaceutical Innovation, 2020Co-Authors: Hussein O. Ammar, Magdy Ibrahim, Azza A. Mahmoud, Rehab N. Shamma, Nada M. HoffyAbstract:Purpose In this study, the preparation of self-assembled polymer-free in situ forming nanovesicles (ISNs) based on non-ionic surfactants (NISs) is presented. Methods A 2^2·4^1 full factorial experimental design was adopted for the development of novel polymer-free ISNs loaded with tenoxicam utilizing the emulsion method. The type of NIS (Brij® 52 or Span® 60), the cholesterol percentage (30, 50, or 60 w/w%), and the internal phase percentage (20 or 30 v/v%) were chosen as the independent variables. Percentage Drug released after 1 h (Q_1), vesicle particle size (PS), and mean dissolution time (MDT) were the dependent variables. Selected formulation was investigated morphologically using transmission electron microscopy. Results Results revealed that the formation had spherical dense shape. All independent factors significantly affected the percentage Drug release after the first hour (Q_1), and the MDT, while only the type of NIS had a significant effect on PS. The highest control of Drug release was observed in formulation containing Span® 60 with lower internal phase percentage (MDT = 20.06 ± 0.40 h) as well as the smallest PS (123.75 ± 16.68 nm). Conclusion The obtained results indicated the potentiality of the invented ISNs in controlling the release of tenoxicam in a desirable economical biphasic pattern compared to other in situ formulations.
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Polymer-Free Injectable In Situ Forming Nanovesicles as a New Platform for Controlled Parenteral Drug Delivery Systems
Journal of Pharmaceutical Innovation, 2020Co-Authors: Hussein O. Ammar, Azza A. Mahmoud, Rehab N. Shamma, Magdy M. Ibrahim, Nada M. HoffyAbstract:In this study, the preparation of self-assembled polymer-free in situ forming nanovesicles (ISNs) based on non-ionic surfactants (NISs) is presented. A 22·41 full factorial experimental design was adopted for the development of novel polymer-free ISNs loaded with tenoxicam utilizing the emulsion method. The type of NIS (Brij® 52 or Span® 60), the cholesterol percentage (30, 50, or 60 w/w%), and the internal phase percentage (20 or 30 v/v%) were chosen as the independent variables. Percentage Drug released after 1 h (Q1), vesicle particle size (PS), and mean dissolution time (MDT) were the dependent variables. Selected formulation was investigated morphologically using transmission electron microscopy. Results revealed that the formation had spherical dense shape. All independent factors significantly affected the percentage Drug release after the first hour (Q1), and the MDT, while only the type of NIS had a significant effect on PS. The highest control of Drug release was observed in formulation containing Span® 60 with lower internal phase percentage (MDT = 20.06 ± 0.40 h) as well as the smallest PS (123.75 ± 16.68 nm). The obtained results indicated the potentiality of the invented ISNs in controlling the release of tenoxicam in a desirable economical biphasic pattern compared to other in situ formulations.
Rainer H. Müller - One of the best experts on this subject based on the ideXlab platform.
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solid lipid nanoparticles for Parenteral Drug Delivery
Advanced Drug Delivery Reviews, 2004Co-Authors: S A Wissing, Oliver Kayser, Rainer H. MüllerAbstract:Abstract This review describes the use of nanoparticles based on solid lipids for the Parenteral application of Drugs. Firstly, different types of nanoparticles based on solid lipids such as “solid lipid nanoparticles” (SLN), “nanostructured lipid carriers” (NLC) and “lipid Drug conjugate” (LDC) nanoparticles are introduced and structural differences are pointed out. Different production methods including the suitability for large scale production are described. Stability issues and Drug incorporation mechanisms into the particles are discussed. In the second part, the biological activity of Parenterally applied SLN and biopharmaceutical aspects such as pharmacokinetic profiles as well as toxicity aspects are reviewed.
Panayiotis P. Constantinides - One of the best experts on this subject based on the ideXlab platform.
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role of lipid excipients in modifying oral and Parenteral Drug Delivery
Drug Development and Industrial Pharmacy, 2008Co-Authors: Panayiotis P. ConstantinidesAbstract:The chemical and physical diversity and versatility of lipid excipients as well as their biocompatibility has resulted in an expanded use in multiple Delivery platforms and marketed Drug products. ...
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Advances in lipid nanodispersions for Parenteral Drug Delivery and targeting.
Advanced drug delivery reviews, 2007Co-Authors: Panayiotis P. Constantinides, Mahesh Chaubal, Robert G. L. ShorrAbstract:Parenteral formulations, particularly intravascular ones, offer a unique opportunity for direct access to the bloodstream and rapid onset of Drug action as well as targeting to specific organ and tissue sites. Triglyceride emulsions, liposomes and micellar solutions have been traditionally used to accomplish these tasks and there are several products on the market using these lipid formulations. The broader application of these lipid systems in Parenteral Drug Delivery, however, particularly with new chemical entities, has been limited due primarily to the following reasons: a) only a small number of Parenteral lipid excipients are approved, b) there is increasing number of Drugs that are partially or not soluble in conventional oils and other lipid solvents, and c) the ongoing requirement for site-specific targeting and controlled Drug release. Thus, there is growing need to expand the array of targetable lipid-based systems to deliver a wide variety of Drugs and produce stable formulations which can be easily manufactured in a sterile form, are cost-effective and at least as safe and efficacious as the earlier developed systems. These advanced Parenteral lipid-based systems are at various stages of preclinical and clinical development which include nanoemulsions, nanosuspensions and polymeric phospholipid micelles. This review article will showcase these Parenteral lipid nanosystems and discuss advances in relation to formulation development, processing and manufacturing, and stability assessment. Factors controlling Drug encapsulation and release and in vivo biodistribution will be emphasized along with in vitro/in vivo toxicity and efficacy case studies. Emerging lipid excipients and increasing applications of injectable lipid nanocarriers in cancer chemotherapy and other disease indications will be highlighted and in vitro/in vivo case studies will be presented. As these new Parenteral lipid systems advance through the clinic and product launch, their therapeutic utility and value will certainly expand.
