Tissue reaction to and biodegradation of two different microcapsule formulations: DLPLA and DLPLGA

1984 ◽  
Vol 42 ◽  
pp. 200-201
Author(s):  
G. E. Visscher ◽  
R. L. Robison ◽  
G. J. Argentieri
Keyword(s):  
Drug Delivery ◽  
Light Microscopy ◽  
Intramuscular Injection ◽  
Drug Delivery Systems ◽  
Delivery Systems ◽  
Tissue Reaction ◽  
Tissue Response ◽  
Male Rats ◽  
Post Injection

It was our goal to characterize the tissue response to and biodegradation of microcapsules of lypressin composed of two different polymers. Microcapsules of lypressin were made with the polymer 50:50 poly (DL-lactide-co-glycolide) DLPLGA and poly (D, L-lactide) DLPLA. The work which is presented here compares the in vivo characteristics of these microcapsules as drug delivery systems.For the study using DLPLGA, 14 groups of male rats were administered, as an intramuscular injection (gastrocnemius), microencapsulated lypressin (1%). Injections of microcapsules were examined through Day 63 of the experiment. In the second study using DLPLA, 27 male rats were injected with microcapsules of lypressin (0.4%) and examined at 30 day intervals through 420 days post injection. Light microscopy was used to characterize the tissue reaction to the injected microcapsules.

Techniques For The Preparation of Tissue Samples Containing Injectable Polymer Microcapsules

1985 ◽  
Vol 43 ◽  
pp. 710-711
Author(s):  
G.E. Visscher ◽  
R. L. Robison ◽  
G. J. Argentieri
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Gastrocnemius Muscle ◽  
Degradation Process ◽  
Delivery Systems ◽  
Tissue Reaction ◽  
Electron Microscopic ◽  
Tissue Samples ◽  
Injectable Polymer ◽  
Microscopic Techniques

The use of various bioerodable polymers as drug delivery systems has gained considerable interest in recent years. Among some of the shapes used as delivery systems are films, rods and microcapsules. The work presented here will deal with the techniques we have utilized for the analysis of the tissue reaction to and actual biodegradation of injectable microcapsules. This work has utilized light microscopic (LM), transmission (TEM) and scanning (SEM) electron microscopic techniques. The design of our studies has utilized methodology that would; 1. best characterize the actual degradation process without artifacts introduced by fixation procedures and 2. allow for reproducible results.In our studies, the gastrocnemius muscle of the rat was chosen as the injection site. Prior to the injection of microcapsules the skin above the sites was shaved and tattooed for later recognition and recovery. 1.0 cc syringes were loaded with the desired quantity of microcapsules and the vehicle (0.5% hydroxypropylmethycellulose) drawn up. The syringes were agitated to suspend the microcapsules in the injection vehicle.

Formulation, Development and Characterization of Floating Beads of Diltiazem Hydrochloride

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Anamika Saxena Saxena ◽  
Santosh Kitawat ◽  
Kalpesh Gaur ◽  
Virendra Singh
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Drug Delivery Systems ◽  
Entrapment Efficiency ◽  
Repeated Administration ◽  
Alginate Beads ◽  
Delivery Systems ◽  
Sem Analysis ◽  
Formulation Development

The main goal of any drug delivery system is to achieve desired concentration of the drug in blood or tissue, which is therapeutically effective and nontoxic for a prolonged period. Various attempts have been made to develop gastroretentive delivery systems such as high density system, swelling, floating system. The recent developments of FDDS including the physiological and formulation variables affecting gastric retention, approaches to design single-unit and multiple-unit floating systems, and their classification and formulation aspects are covered in detail. Gastric emptying is a complex process and makes in vivo performance of the drug delivery systems uncertain. In order to avoid this variability, efforts have been made to increase the retention time of the drug-delivery systems for more than 12 hours. The floating or hydrodynamically controlled drug delivery systems are useful in such application. Background of the research: Diltiazem HCL (DTZ), has short biological half life of 3-4 h, requires rather high frequency of administration. Due to repeated administration there may be chances of patient incompliance and toxicity problems. Objective: The objective of study was to develop sustained release alginate beads of DTZ for reduction in dosing frequency, high bioavailability and better patient compliance. Methodology: Five formulations prepared by using different drug to polymer ratios, were evaluated for relevant parameters and compared. Alginate beads were prepared by ionotropic external gelation technique using CaCl2 as cross linking agent. Prepared beads were evaluated for % yield, entrapment efficiency, swelling index in 0.1N HCL, drug release study and SEM analysis. In order to improve %EE and drug release, LMP and sunflower oil were used as copolymers along with sodium alginate.

Nanostructured Ketorolac-Tromethamine/MCF: Synthesis, Characterization and Application in Drug Release System

2018 ◽  
Vol 14 (5) ◽  
pp. 432-439 ◽  
Author(s):  
Juliana M. Juarez ◽  
Jorgelina Cussa ◽  
Marcos B. Gomez Costa ◽  
Oscar A. Anunziata
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Therapeutic Efficacy ◽  
Drug Delivery Systems ◽  
Controlled Drug Release ◽  
Delivery Systems ◽  
The Body ◽  
Fickian Diffusion ◽  
Ketorolac Tromethamine

Background: Controlled drug delivery systems can maintain the concentration of drugs in the exact sites of the body within the optimum range and below the toxicity threshold, improving therapeutic efficacy and reducing toxicity. Mesostructured Cellular Foam (MCF) material is a new promising host for drug delivery systems due to high biocompatibility, in vivo biodegradability and low toxicity. Methods: Ketorolac-Tromethamine/MCF composite was synthesized. The material synthesis and loading of ketorolac-tromethamine into MCF pores were successful as shown by XRD, FTIR, TGA, TEM and textural analyses. Results: We obtained promising results for controlled drug release using the novel MCF material. The application of these materials in KETO release is innovative, achieving an initial high release rate and then maintaining a constant rate at high times. This allows keeping drug concentration within the range of therapeutic efficacy, being highly applicable for the treatment of diseases that need a rapid response. The release of KETO/MCF was compared with other containers of KETO (KETO/SBA-15) and commercial tablets. Conclusion: The best model to fit experimental data was Ritger-Peppas equation. Other models used in this work could not properly explain the controlled drug release of this material. The predominant release of KETO from MCF was non-Fickian diffusion.

scholarly journals Mechanisms and Pharmaceutical Action of Lipid Nanoformulation of Natural Bioactive Compounds as Efficient Delivery Systems in the Therapy of Osteoarthritis

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1108
Author(s):  
Oana Craciunescu ◽  
Madalina Icriverzi ◽  
Paula Ecaterina Florian ◽  
Anca Roseanu ◽  
Mihaela Trif
Keyword(s):  
Drug Delivery ◽  
Bioactive Compounds ◽  
Targeted Delivery ◽  
Drug Delivery Systems ◽  
Delivery Systems ◽  
Joint Disease ◽  
Duration Of Action ◽  
Immune System Activation

Osteoarthritis (OA) is a degenerative joint disease. An objective of the nanomedicine and drug delivery systems field is to design suitable pharmaceutical nanocarriers with controllable properties for drug delivery and site-specific targeting, in order to achieve greater efficacy and minimal toxicity, compared to the conventional drugs. The aim of this review is to present recent data on natural bioactive compounds with anti-inflammatory properties and efficacy in the treatment of OA, their formulation in lipid nanostructured carriers, mainly liposomes, as controlled release systems and the possibility to be intra-articularly (IA) administered. The literature regarding glycosaminoglycans, proteins, polyphenols and their ability to modify the cell response and mechanisms of action in different models of inflammation are reviewed. The advantages and limits of using lipid nanoformulations as drug delivery systems in OA treatment and the suitable route of administration are also discussed. Liposomes containing glycosaminoglycans presented good biocompatibility, lack of immune system activation, targeted delivery of bioactive compounds to the site of action, protection and efficiency of the encapsulated material, and prolonged duration of action, being highly recommended as controlled delivery systems in OA therapy through IA administration. Lipid nanoformulations of polyphenols were tested both in vivo and in vitro models that mimic OA conditions after IA or other routes of administration, recommending their clinical application.

Self-assembled drug delivery systems. Part 6: In vitro/in vivo studies of anticancer N-octadecanoyl gemcitabine nanoassemblies

2012 ◽  
Vol 430 (1-2) ◽  
pp. 276-281 ◽  
Author(s):  
Yiguang Jin ◽  
Yanju Lian ◽  
Lina Du ◽  
Shuangmiao Wang ◽  
Chang Su ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Delivery Systems ◽  
In Vivo Studies ◽  
Self Assembled

scholarly journals Polymer-Based Smart Drug Delivery Systems for Skin Application and Demonstration of Stimuli-Responsiveness

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1285
Author(s):  
Louise Van Gheluwe ◽  
Igor Chourpa ◽  
Coline Gaigne ◽  
Emilie Munnier
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Ex Vivo ◽  
Delivery Systems ◽  
Stimuli Responsive ◽  
Stimuli Responsive Polymers ◽  
Smart Drug ◽  
Smart Drug Delivery

Progress in recent years in the field of stimuli-responsive polymers, whose properties change depending on the intensity of a signal, permitted an increase in smart drug delivery systems (SDDS). SDDS have attracted the attention of the scientific community because they can help meet two current challenges of the pharmaceutical industry: targeted drug delivery and personalized medicine. Controlled release of the active ingredient can be achieved through various stimuli, among which are temperature, pH, redox potential or even enzymes. SDDS, hitherto explored mainly in oncology, are now developed in the fields of dermatology and cosmetics. They are mostly hydrogels or nanosystems, and the most-used stimuli are pH and temperature. This review offers an overview of polymer-based SDDS developed to trigger the release of active ingredients intended to treat skin conditions or pathologies. The methods used to attest to stimuli-responsiveness in vitro, ex vivo and in vivo are discussed.

Sign in / Sign up

Export Citation Format

Share Document