• Archives of Pharmacal Research
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• 제19권1호
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• pp.1-5
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• 1996

Laminated films composed of drug-containing reservoir layer and drug-free membrane were prepared. Zero-order drug release with lag time was achieved by laminating drug-free film onto the reservoir layer, while burst effect was observed on cast-on film. The rate controlling membrane was either attached to or cast directly into the reservoir. The release rate was independent on the reservoir composition but dependent on the composition of rate-controlling membrane. In growth inhibitory test of cephalexin from Eudragit RS film to Streptococcus Mutans, the disk even after release test for 72 hours showed more bacterial growth inhibition than that of control. Permeation of drug through rat skin was proportional to the HPC fraction in the film. We could control the release of cephalexin from the film by changing the fraction of Eudragit RS, HPC and DEP content. Consequently, Eudragit RS/HPC film was found to be very effective system for local delivery of drugs.

• Macromolecular Research
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• 제11권4호
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• pp.207-223
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• 2003

For last five years, we are developing the novel local drug delivery devices using biodegradable polymers, especially polylactide (PLA) and poly(D,L-lactide-co-glycolide) (PLGA) due to its relatively good biocompatibility, easily controlled biodegradability, good processability and only FDA approved synthetic degradable polymers. The relationship between various kinds of drug [water soluble small molecule drugs: gentamicin sulfate (GS), fentanyl citrate (FC), BCNU, azidothymidine (AZT), pamidronate (ADP), $1,25(OH)_2$ vitamin $D_3$, water insoluble small molecule drugs: fentanyl, ipriflavone (IP) and nifedipine, and water soluble large peptide molecule drug: nerve growth factor (NGF), and Japanese encephalitis virus (JEV)], different types of geometrical devices [microspheres (MSs), microcapsule, nanoparticle, wafers, pellet, beads, multiple-layered beads, implants, fiber, scaffolds, and films], and pharmacological activity are proposed and discussed for the application of pharmaceutics and tissue engineering. Also, local drug delivery devices proposed in this work are introduced in view of preparation method, drug release behavior, biocompatibility, pharmacological effect, and animal studies. In conclusion, we can control the drug release profiles varying with the preparation, formulation and geometrical parameters. Moreover, any types of drug were successfully applicable to achieve linear sustained release from short period ($1{\sim}3$ days) to long period (over 2 months). It is very important to design a suitable formulation for the wanting period of bioactive molecules loaded in biodegradable polymers for the local delivery of drug. The drug release is affected by many factors such as hydrophilicity of drug, electric charge of drug, drug loading amount, polymer molecular weight, the monomer composition, the size of implants, the applied fabrication techniques, and so on. It is well known that the commercialization of new drug needs a lot of cost of money (average: over 10 million US dollar per one drug) and time (average: above 9 years) whereas the development of DDS and high effective generic drug might be need relatively low investment with a short time period. Also, one core technology of DDS can be applicable to many drugs for the market needs. From these reasons, the DDS research on potent generic drugs might be suitable for less risk and high return.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.236.1-236.1
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• 2002

Mucosal administration of drug or therapeutic gene is emerging as a new route of delivery for systemic and local therapeutics. Previously. in situ gelling system has been applied to chemical drug such as acetaminophen. insulin. prostaglandin E1. and clotrimazole. Plasmid DNA has not been delivered in form of in situ gelling vehicles. To improve the intranasal absorption of plasmid DNA. we designed delivery systems composed of provide of in 냐셔 gelling and mucoadhesive polymers. (omitted)

• Journal of Pharmaceutical Investigation
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• 제25권3호spc1호
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• pp.33-35
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• 1995

Microspheres containing tetracaine or bupivacaine with poly-lactic-glycolic acid were prepared with a range of compositions. Using the rat scicatic nerve model in vivo it was found that prolonged blockade for periods of 2-7 days. depending on composition variables. Polymer-local anesthetics microspheres are feasible delivery vehicle for prolonged regional nerve blockade.

• Biomaterials and Biomechanics in Bioengineering
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• 제5권1호
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• pp.65-86
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• 2020

As conventional drug delivery system is being improved rapidly by target-based drug delivery system, finding suitable Drug Delivery System (DDS) for new drugs remains a challenge. Although there are many drug delivery vehicles in existence, a significant improvement is required to some DDS such as for local, implant-based treatments used for musculoskeletal infections. Many polymers have been considered for providing the improvement in DDS. Synthetic polymer, for example, has gained popularity for broad-spectrum physicochemical and mechanical properties. This article reviews the biomedical applications of Poly(TriMethylene Carbonate-co-Caprolactone) (PTMCC), which has attracted attention due to its biocompatibility, biodegradability and rubber-like properties. Its synthesis, physical properties, and degradation are also discussed here. Although it is relatively new in biomedical applications, it is readily usable for the fabrication of differing format of DDS of superior mechanical strength and degradation properties. The use of PTMCC is expected to increase in coming years as more is revealed about its potentials.

• Macromolecular Research
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• 제13권1호
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• pp.54-61
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• 2005

We prepared temperature-sensitive liposomes (TS-liposomes) modified with a thermo sensitive polymer, such as poly(N-isopropylacrylamide) (PNIPAAm), to increase the degree of drug release from liposomes at the hyperthermic temperature. A PNIPAAm hydrogel containing TS-Iiposomes was also prepared to obtain a hydrogel complex at body temperature. In addition, a depot system for local drug delivery using the polymer hydrogel was developed to enhance therapeutic efficacy and prevent severe side effects in the whole body. The PNIPAAm-mod­ified TS-liposome was fixed into the PNIPAAm hydrogel having a high temperature-sensitivity. The release behavior of calcein, a model drug, from TS-liposomes in the PNIPAAm hydrogel was then initiated by external hyperthermia; the results indicated that sustained release as a function of temperature and time was caused by the thermosensitivity of the liposome surface and diffusion of the drug into the PNIPAAm hydrogel. Our results indicated that TS-liposomes in a PNIPAAm hydrogel represented a plausible system for local drug delivery.

• Bulletin of the Korean Chemical Society
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• 제28권3호
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• pp.397-402
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• 2007

Restenosis after percutaneous coronary intervention (PCI) continues to be a serious problem in clinical cardiology. To solve this problem, drug eluting stents (DES) with antiproliferative agents have been developed. Variable local drug delivery systems in the context of stenting require the development of stent manufacture, drug pharmacology and coating technology. We have worked on a system that integrates electrophoretic deposition (EPD) technology with the polymeric nanoparticles in DES for local drug delivery and a controlled release system. The surface morphology and drug loading amount of DES by EPD have been investigated under different operational conditions, such as operation time, voltage and the composition of media. We prepared poly-D,L-lactide-co-glycolic acid (PLGA) nanoparticles embedded with curcumin, which was done by a modified spontaneous emulsification method and used polyacrylic acid (PAA) as a surfactant because its carboxylic group contribute negative charge to the surface of CPNPs (?53.5 ± 5.8 mV). In the process of ‘trial and error' endeavors, we found that it is easy to control the drug loading amount deposited onto the stent while keeping uniform surface morphology. Accordingly, stent coating by EPD has a wide application to the modification of DES using various kinds of nanoparticles and drugs.

• Journal of Periodontal and Implant Science
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• 제44권3호
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• pp.118-125
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• 2014

Purpose: The present split mouth study evaluates the effect of nonsurgical periodontal treatment on the gingival crevicular fluid (GCF) leptin level in chronic periodontitis. Methods: Ninety sites from 30 nonobese chronic periodontitis patients were selected and divided as follows: group I, 30 healthy sites receiving no treatment; group II, 30 periodontitis sites receiving scaling and root planing (SRP); and group III, 30 periodontitis sites receiving SRP with tetracycline local drug delivery. At baseline, after GCF sampling and clinical parameter recording, the assigned treatment was performed for the study groups. During recall visits, GCF sampling followed by clinical parameter recording was done for groups II and III. Results: Reductions in the probing depth and the clinical attachment level (CAL) were highly significant at different time intervals (except between day 0 and 45) in both groups II and III. Upon comparison, group III showed significant gain in CAL between day 0 and 15 and between day 0 and 45. After treatment, the reduction in the GCF leptin level was more significant in group III than in group II at day 15 but re-elevated almost to the pretreatment levels at day 45. Conclusions: Nonsurgical periodontal therapies were not effective in maintaining stable reduction in the GCF leptin level during the study period.

• Journal of Pharmaceutical Investigation
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• 제40권spc호
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• pp.113-118
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• 2010

Pharmaceutical technology has primarily focused on the development of the best dosage forms depending on the route of administration. The design of dosage forms is greatly influenced by the route of administration. Due to a variety of advantages such as avoidance of first-pass effect, abundant blood supply and easy access to the absorption site, the oral cavity has frequently been selected as a site for drug delivery. Since the oral cavity is relatively unique from the anatomical and physiological viewpoint, one should always consider these conditions when designing the drug delivery systems for the oral cavity. In this regard, the current review paper was prepared to summarize the essential features of the drug delivery systems utilized in the oral cavity, along with the introduction of various dosage forms developed to date.

• 셀메드
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• 제11권1호
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• pp.6.1-6.7
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• 2021

In situ gelling devices, as they enter the body, are dosage forms in the shape of the sol but turn into gel types under physiological circumstances. Transition from sol to gel is contingent on one or a mixture of diverse stimuli, such as transition of pH control of temperature, irradiation by UV, by the occurrence of certain ions or molecules. Such characteristic features may be commonly employed in drug delivery systems for the production of bioactive molecules for continuous delivery vehicles. The technique of in situ gelling has been shown to be impactful in enhancing the potency of local or systemic drugs supplied by non-parenteral pathways, increasing their period of residence at the absorption site. Formulation efficacy is further improved with the use of mucoadhesive agents or the use of polymers with both in situ gelling properties and the ability to bind with the mucosa/mucus. The most popular and common approach in recent years has provided by the use of polymers with different in situ gelation mechanisms for synergistic action between polymers in the same formulation. In situ gelling medicine systems in recent decades have received considerable interest. Until administration, it is in a sol-zone and is able to form gels in response to various endogenous factors, for e.g elevated temperature, pH changes and ions. Such systems can be used in various ways for local or systemic supply of drugs and successfully also as vehicles for drug-induced nano- and micro-particles. In this review we will discuss about various aspects about use of these in situ gels as novel drug delivery systems.