Papers by Keyword: Drug Delivery System

Abstract: Conventional drug delivery systems face challenges like low bioavailability, rapid degradation and limited effectiveness in drug delivery, especially for persistent infections. Our research focus to develop nanofiber drug delivery systems (NDDSs) using biopolymers like starch and gelatine. In this study, nanofilm was produced using polylactic acid (PLA), Nanocrystalline Cellulose (NCC), gelatine/starch, and paracetamol (acetaminophen) as the drug at different ratios. From SEM, the best ratio for gelatine-based nanofilm was 6% PLA: 0.5% gelatine : 0.15% NCC : 0.02% drug while starch-based nanofilm the best ratio was 8% PLA: 0.2% starch: 0.15% NCC: 0.02% drug. In drug release kinetics study, the results were compared using mathematical models such as zero order, first order, and Higuchi models for both types of bio-based nanofilm. The drug release kinetics results indicate that the starch-based nanofilm was superior to the gelatin-based nanofilm in drug delivery, fitting both the Higuchi and Zero-order models.

Abstract: Zeolitic imidazolate frameworks-8 (ZIF-8), a type of metal-organic frameworks (MOFs), displays high porosity, large surface areas, and tunable functionality in nanocomposites, promising carrier for drug delivery applications. In this work, ZIF-8 nanomaterials were synthesized via precipitation under three different conditions and subsequently loaded onto chitosan/pluronic F-127 (CS/PL) hydrogels. The ZIF-8 materials prepared in NH₄OH solution (ZIF-8-NH₄OH) showed a regular cubic shape with a large particle size of approximately 963 nm due to the acceleration of crystal growth in a basic medium. Meanwhile, the ZIF-8 species prepared in H₂O and MeOH (ZIF-8-H₂O and ZIF-8-MeOH, respectively) displayed crystal sizes of approximately 152 and 240 nm, respectively. The overall toxicity of the ZIF-8 nanomaterials was determined with an XTT assay against the L929 mouse fibroblast cell line. The morphology of the cells was altered at a concentration of over 30 µg/mL due to cell membrane deformations. This result correlated with the lactate dehydrogenase (LDH) release study by detection of LDH release at a concentration of over 25 µg/mL (50% LDH release). To reduce the toxicity of the ZIF-8 materials, CS/PL hydrogels were appropriately prepared and used to encapsulate the ZIF-8 at 0.095% w/w. Cytotoxicity results of the ZIF-8-loaded CS/PL hydrogels indicated over 75% cell viability of the L929 cells. These results presented significant implications for future applications of the ZIF-8 particles in the delivery of drugs or other compounds.

Abstract: Pseudoboehmite is an aluminium compound with a structure similar to that of boehmite. The unit cell of the pseudoboehmite is slightly larger than that of the boehmite because of the greater incorporation of water in the same structure [1]. It has particles of nanometric dimensions and can be synthesized with extremely high purity. Several papers published in the literature show the potential of using this material in the controlled release of drugs, including cancer treatment [2,3]. Using drugs in complexes incorporated into polymer matrices and ceramic gels can lead to adequate control of gastrointestinal absorption when administered orally. Consequently, there is the possibility of promoting a gradual action through the progressive release of the drug, thus increasing its efficiency and reducing dose and toxicity. Previous studies have shown that pseudoboehmite is non-toxic and can be used for drug delivery. During the tests to determine the toxicity of this material, it was observed that the blood glucose content was reduced in mice that took pseudoboehmite by gavage. Since pseudoboehmite is obtained via low-cost inorganic synthesis, different physicochemical characteristics can be incorporated into this high purity medium. The formed structure was evaluated as a drug delivery system to establish a profile of the influence of the physicochemical properties of a molecule in the process of interaction with pseudoboehmite, a drug with recognized pharmacological activity, simvastatin (IUPAC name (1S,3R,7S,8S,8aR)-8-{2-[(2R,4R)-4-hydroxy-6-oxooxan-2-yl]ethyl}-3,7-dimethyl-1,2,3,7,8,8a-hexahydronaphthalen-1-yl 2,2-dimethylbutanoate) was choose. It also emphasizes the importance of pseudoboehmite as a drug carrier, serving as a precursor to new therapeutic systems. The synthesis of pseudoboehmite from ammonium hydroxide and aluminium nitrate was optimized to release simvastatin in vitro. After absorption and hydrolysis in the liver to form the active β-hydroxy acid metabolite, simvastatin acts as a potent reversible, competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an early and rate-limiting enzyme in the biosynthesis of cholesterol.

Abstract: Electrospinning is considered a promising technology for encapsulating and loading various drugs into nanofibers. Metoprolol tartrate (MPT), hydrophilic therapy, was used as model drug. Metoprolol tartrate was loaded into poly(ɛ-caprolactone) (PCL) via blend and emulsion electospinning. The preparation processes, morphology, chemical structure thermal properties were evaluated. FESEM showed that emulsion electospinning produce larger fiber diameters(301.775nm) when compared to fibers produced by blend electrospinning(112.463, 249.34)nm, the PCL/ span 80 and MPT-PCL by emulsion method which have high fiber diameter than pure PCL and MPT-PCL by blend method and the Tm of pure PCL nanofibers and all drug loaded scaffolds are around 60°C from DSC test, water contact angle to pure PCL electrospun mats hydrophobic character (126.2°), while PCL/span 80, and PCL-drug nanofiber mats showed hydrophilic character. Our study demonstrated the possibility of using electrospinning with a promising good potential toward sustained and controlled drug delivery system.

Abstract: Exploration of natural compound for the treatment of dental-related problems are gaining of interest for enhancing therapeutic efficacy of the drugs delivery system. In this study, we have prepared terpenoid, which have been isolated from Myrmecodia pendens Merr & Perry from Papua Island, Indonesia, to be encapsulated in Polylactic-co-glycolic acid (PLGA), as the most widely used biodegradable polymer for biomedical applications, through one step single-emulsion method followed by subsequent coating by poly (vinyl alcohol) (PVA). The resultant of terpenoid-loaded PLGA microparticles were characterized systematically through scanning electron microscope and Fourier-transform infrared spectroscopy. In vitro drug release test was evaluated through dialysis method. Antibacterial test was conducted against Enterococcus faecalis as a model for persistent bacteria that causes root canal infections. The results showed that terpenoid-loaded PLGA microparticles were developed in spherical morphology with an average particle size of around 1-2μm. Terpenoid released from PLGA compartment at pH 6.5 and temperature of 37°C through a controlled-release profile mechanism with enhanced prolonged release. The bacterial assay result showed that terpenoid-loaded PLGA microparticles could reduce Enterococcus faecalis, effectively. Eventually, these result show that terpenoid-loaded PLGA microparticles as unique natural product-based extract could be developed as a potential naturally-based drug for dental-related diseases applications.

Abstract: The bone remodeling process plays an essential part of the calcium homeostatic system and provides a crucial mechanism for adaptation to physical stress, the repair of damaged bone and the removal of old bone. We reported previously that sustainable release of simvastatin (SIM) from poly (lactic-co-glycolic acid) (PLGA) formulations could induce bone formation. The aim of this study was to develop a simvastatin-releasing PLGA/β-TCP composite microspheres (β-SPMs) sintered scaffolds (β-SPMSS) as a synthetic bone substitute, and investigate the influence of the dissolution medium on the drug release capabilities of these device based on a physicochemical model for bone remodeling. X-ray diffraction analysis (XRD) results showed β-TCP and SIM could be encapsulated into the PLGA microspheres. The β-SPMs and the β-SPMSS were able to produce sustained release of SIM for 1 month in simulated body fluid (SBF), whereas these composites released SIM for 10 days in acetate buffer (AB). The release rate of SIM from β-SPMSS in AB was faster than in SBF, indicating that the β-SPMSS could control drug release with bone cells activity response, and could be used as a scaffold in bone remodeling area. These results suggested that the β-SPMSS could release SIM sustainably, with bone cells activity response, and could be used as a scaffold in bone remodeling area.

Abstract: In drug delivery system, a controlled drug delivery carrier is favorable to ensure the delivery of drug at suitable and required rate and dosage to the targeted area. Microsphere is one of the approaches used to deliver drug in a controlled manner. A biodegradable poly (lactic) acid (PLA) has been used widely for drug delivery due to the fact that the polymer was non-toxic with a biodegradable property. Therefore, PLA microspheres were utilized in this research works. On the other hand, the major drawback of PLA is its extremely hydrophobic properties which limit its application in drug delivery system. In order to overcome this problem, surface modification via alkaline hydrolysis has been made on PLA. This research investigated the effect of surface modification with sodium boronhydride (NaBH₄) at different concentrations and temperatures on the properties of PLA microspheres. The enhancement of hydrophilicity of PLA microspheres has been evaluated using FTIR and SEM. From these evaluations, it was found that the hydrophilicity of PLA microspheres had increased as the concentration of NaBH₄ and temperature increased.

Abstract: Drug delivery systems using polymeric materials have been under intensive investigation and have been reported to show effective drug targeting specificity, lowering system drug toxicity, improving treatment absorption rates, and providing enteric coatings against biochemical degradation. The layer–by–layer (Lbl) assembly of polyelectrolytes through electrostatic interactions can be readily tailored to control the size, structure, and stability of the film and microcapsules. In this study, microcapsules were fabricated by alternately depositing poly (dimethyldiallylammonium chloride) PDDA, glucose oxidase (GOx), and polyacrylic acid (PAA) to form multilayer shells on a MnCO₃ template and onto insulin particles by Lbl method. Also, the physical characteristic and release mechanism of thin films incorporating insulin sandwiched between [2(dimethyl amino) ethyl methacrylate] (PDMAEMA), with polymer/GOx layers were compared with the fabricated microcapsules. The synthesized shells have shown stability at pH 4 and become unstable at neutral pH. The fabricated insulin loaded microcapsules and films showed an on–off mechanism in the presence of glucose. Exposure to glucose solutions resulted in the production of gluconic acid; as a result, there was a change in the conformation of the polymer, releasing the embedded insulin. The drug release profiles observed indicates their potential application for the controlled release of insulin.

Abstract: The specific objective of this investigation is to study the effect of tetracalcium phosphate (TeCP) delivery system fabricated from three different particle sizes (<38, 45 and 75 um) on the viability of HL-60 cell line in culture. Each TeCP reservoir was fabricated using standard protocols. The sintered microcrystal material were cold pressed at 5000 kg compression load, sterilized and loaded into wells pre-plated with 10⁶ HL-60 cells. At the end of 24, 48, and 72 hours, the supernatants (cell suspension) from the wells were collected for cell count (a hemacytometer method) and lactate dehydrogenase (LDH) assays. The cells were evaluated for structural cellular damage by using conventional histopathological protocols (H&E stain). Results obtained from this investigation suggest the followings: (i) particle sizes are key elements in developing TeCP delivery system, (ii) the use of <38 um particle sizes would be favorable for long duration of delivering biologicals from the TeCP reservoirs due to the viability of HL-60 cells, (iii) LDH activities were directly proportional the particle sizes of the ceramic capsules compared to the control and (iv) there were less cellular structural changes in devices fabricated from <38 um particle sizes and the cells became more reactive with an increase in particle sizes.

Abstract: Recently, the incidence of American Cutaneous Leishmaniasis (ACL) has been grown in Latin America, especially in Brazil, where from 1980 to 2005, 605,062 cases were recorded. The drug glucantime®, whose active principle is the meglumine antimoniate (or meglumine antimonate) is used in the treatment of leishmaniasis. Its toxicity is due mainly to the presence of antimony in its structure. Therefore, it is crucial to determine the safe dose levels of this drug in the treatment. Drug delivery systems have been currently the focus of many studies due to its effectiveness in treating diseases proved to be superior compared to conventional methods. Drug delivery systems can avoid overdosing by decreasing the amount of drug intake, which results in a better therapeutic effect in addition to reducing the risks of plasma concentration reaching toxic levels. Synthetic nanomaterials have been receiving great attention due to their potential applications in pharmaceutical technology as well as the possibility of controlling their particle size and composition, which allows a better performance in drug release. Pseudoboehmite is a synthetic aluminum compound precursor of alumina [1] and a polymorph of boehmite, with active groups in its structure [2], making it an excellent adsorbent material. In this work, pseudoboehmite was prepared by using the sol-gel process for being used as an excipient. The incorporation of pseudoboehmite in glucantime® was performed in the processing of tablets. Both pseudoboehmite and the tablets were characterized via X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG), and scanning electron microscopy (SEM) using secondary electron detector and EDS detector. The release profile was obtained by UV/Vis spectroscopy for in vitro simulation. No reaction between the drug and the excipient was observed.