• Journal of Pharmaceutical Investigation
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• 제39권6호
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• pp.437-443
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• 2009

To develop a topical bioadhesive formulation of clotrimazole for enhanced transdermal delivery, hydroxypropyl methylcellulose gel containing permeation enhancer was formulated and permeation studies were carried out. The release characteristics of the drug from the gel formulation were examined according to the receptor medium, drug concentration, and temperature. The rate of drug release from the gel increased with increasing drug concentration and temperature. The activation energy (Ea) of drug permeation, which was calculated from the slope of log P versus 1/T plots, was 14.41kcal/mol for a 1%(w/w) loading dose. The enhancer, such as saturated, unsaturated fatty acids, pyrrolidones, propylene glycol derivatives, glycerides, and non-ionic surfactants, were incorporated onto the gels to increase the amount of drug permeation into the skin. Among the enhancers used, polyoxyethylene 2-oleyl ether showed the highest level of enhancement. These results show that clotrimazole gels containing polyoxyethylene 2-oleyl ether could be used for the enhanced transdermal delivery of clotrimazole.

• 대한의용생체공학회:의공학회지
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• 제33권4호
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• pp.202-206
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• 2012

In this study, we developed transdermal direct drug delivery device using micro-needle painlessly. We has fabricated micro-needle that is 130 ${\mu}m$ thickness and 250 ${\mu}m$length with 10 ${\mu}m$ spiral groove for rolling down drug. Head part of micro-needle device is composed of 20ea micro-needles, an on-off valve and a protective cap. Glass bottle for containing drug is connected to head part of micro-needle device. We examined the puncture characteristic testing using porcine skin and drug delivery testing using porcine, rat skin with Indian Ink.

• Macromolecular Research
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• 제15권6호
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• pp.547-552
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• 2007

Water soluble polymer, poly(vinyl pyrrolidone) was chosen to conjugate with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(succinyl) (N-succinyl DPPE) to make a new drug delivery system. PVP with an amine group (amino-PVP) was polymerized by free radical polymerization. The amine group of amino-PVP was conjugated with the carboxylic group of N-succinyl DPPE. The resultant conjugate could form nanoparticles in the aqueous solution; these nanoparticles were termed a lipid-polymer system. The critical aggregation concentration was measured with pyrene to give a value of $1{\times}10^{-3}g/L$. The particle size of the lipid-polymer system, as measured by DLS, AFM and TEM, was about 70 nm. Lipophilic component in the inner part of the lipid-polymer system could derive the physical interaction with hydrophobic drugs. Griseofulvin was used as a model drug in this study. The loading efficiency and release profile of the drug were measured by HPLC. The loading efficiency was about 54%. The release behavior was sustained for a prolonged time of 12 days. The proposed lipid-polymer system with biodegradable and biocompatible properties has promising potential as a passive-targeting drug delivery carrier because of its small particle size.

• Macromolecular Research
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• 제15권7호
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• pp.646-655
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• 2007

To achieve targeted drug delivery for chemotherapy, a ligand-mediated nanoparticulate drug carrier was designed, which could identity a specific receptor on the surfaces of tumor cells. Biodegradable poly(ethylene oxide)/poly$({\varepsilon}-caprolactone)$ (PEG/PCL) amphiphilic block copolymers coupled to biotin ligands were synthesized with a variety of PEG/PCL compositions. Block copolymeric nanoparticles harboring the anticancer drug paclitaxel were prepared via micelle formation in aqueous solution. The size of the biotin-conjugated PEG/PCL nanoparticles was determined by light scattering measurements to be 88-118 nm, depending on the molecular weight of the block copolymer, and remained less than 120 nm even after paclitaxel loading. From an in vitro release study, biotin-conjugated PEG/PCL nanoparticles containing paclitaxel evidenced sustained release profiles of the drug with no initial burst effect. The biotin-conjugated PEG/PCL block copolymer itself evidenced no significant adverse effects on cell viability at $0.005-1.0{\mu}g/mL$ of nanoparticle suspension regardless of cell type (normal human fibroblasts and HeLa cells). However, biotin-conjugated PEG/PCL harboring paclitaxel evidenced a much higher cytotoxicity for cancer cells than was observed in the PEG/PCL nanoparticles without the biotin group. These results showed that the biotin-conjugated nanoparticles could improve the selective delivery of paclitaxel into cancer cells via interactions with over-expressed biotin receptors on the surfaces of cancer cells.

• Medical Lasers
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• 제10권3호
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• pp.181-184
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• 2021

Scars can cause great psychological stress among patients. Currently, there are numerous topical agents, laser and surgical treatments available for skin rejuvenation and scar minimization. Laser-assisted drug delivery (LADD) is a treatment method that increases drug delivery by stimulating the skin physically and chemically to enhance the penetration of topical agents. This is one of the areas of great interest in the treatment of various skin diseases in addition to its use for cosmetic purposes. In particular, LADD is relatively non-invasive and has advantages in terms of accessibility and stability. Poly-L-lactic acid (PLLA) is a collagen stimulator known to gradually restore skin volume by inducing inflammation and fibroplasia. Herein, we report a case of treatment of an atrophic scar with fractional carbon dioxide laser-assisted PLLA delivery.

• Archives of Pharmacal Research
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• 제29권7호
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• pp.598-604
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• 2006

In many conventional drug delivery systems in vogue, failure to deliver efficient drug delivery at the target site/organs; is evident as a result, less efficacious pharmacological response is elicited. Microspheres can be derived a remedial measure which can improve site-specific drug delivery to a considerable extent. As an application, Lung-targeting Ofloxacin-loaded gelatin microspheres (GLOME) were prepared by water in oil emulsion method. The Central Composite Design (CCD) was used to optimize the process of preparation, the appearance and size distribution were examined by scanning electron microscopy, the aspects such as in vitro release characteristics, stability, drug loading, loading efficiency, pharmacokinetics and tissue distribution in albino mice were studied. The experimental results showed that the microspheres in the range of $0.32-22\;{\mu}m$. The drug loading and loading efficiency were 61.05 and 91.55% respectively. The in vitro release profile of the microspheres matched the korsmeyer’s peppas release pattern, and release at 1h was 42%, while for the original drug, ofloxacin under the same conditions 90.02% released in the first half an hour. After i.v. administration (15 min), the drug concentration of microspheres group in lung in albino mice was $1048\;{\mu}g/g$, while that of controlled group was $6.77\;{\mu}g/g$. GLOME found to release the drug to a maximum extent in the target tissue, lungs.

• 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.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.736-742
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• 2005

Xyloglucan (XG), which exhibits thermal sol to gel transition, non-toxicity, and low gelation concentration, is of interest in the development of sustained release carriers for drug delivery. Drug-loaded XG beads were prepared by extruding dropwise a dispersion of indomethacin in aqueous XG solution (2 wt.-$\%$) through a syringe into corn oil. Enteric coating of XG bead was performed using Eudragit L 100 to improve the stability of XG bead in gastrointestinal (GI) track and to achieve gastroresistant drug release. Release behavior of indomethacin from XG beads in vitro was investigated as a function of loading content of drug, pH of release medium, and concentration of coating agent. Adhesive force of XG was also measured using the tensile test. Uniform-sized spherical beads with particle diameters ranging from 692 $\pm$ 30 to 819 $\pm$ 50 $\mu$m were obtained. The effect of drug content on the release of indomethacin from XG beads depended on the medium pH. Release of indomethacin from XG beads was retarded by coating with Eudragit and increased rapidly with the change in medium pH from 1.2 to 7.4. Adhesive force of XG was stronger than that of Carbopol 943 P, a well-known commercial mucoadhesive polymer, in wet state. Results indicate the enteric-coated XG beads may be suitable as a carrier for oral drug delivery of irritant drug in the stomach.

• Journal of Pharmaceutical Investigation
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• 제23권3호spc1호
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• pp.41-50
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• 1993

The iontophoretic delivery across rat skin of quaternary ammonium salts (isopropamide: ISP, pyridostigmine: PS), which are positively charged over a wide pH range, was measured ill vitro. The study showed that: (a) iontophoresis significantly enhanced delivery of ISP and PS compared to respective passive transport; (b) delivery of ISP and PS was directly proportional to the applied continuous direct current density over the range of $0-0.69\;mA/cm^2;$ (c) delivery of ISP and PS was also proportional to the drug concentration in the donor compartment over the range of $0-2{\time}l0^{-2}M:$ (d) sodium ion in the donor compartment inhibited the drug transport possibly due to decreasing the electric transference number of the drug; (e) delivery of ISP and PS increased as the pH of the donor solution increased over the pH range 2-7 suggesting permselective nature of the epidermis, and inhibition of the transference number of the drugs by hydronium ion; (f) some organic anions such as taurodeoxycholate, salicylate and benzoate which form lipophilic ion-pair complexes with ISP inhibited the delivery of ISP. The degree of inhibition by the organic anions was linearly proportional to the extraction coefficient $(K_e)$ of ISP from the partition system with each counteranion between phosphate buffer (pH 7.4) and n-octanol. For PS, however, taurodeoxycholate, but not salicylate and benzoate inhibited the iontophoretic delivery. It suggests that not only sodium ion and hydronium ion but also the counteranions which form lipophilic ion-pairs with quaternary ammonium drugs are not favorable components in formulating the donor solution of the drugs to achieve an effective iontophoretic delivery.

• Archives of Pharmacal Research
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• 제8권3호
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• pp.159-168
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• 1985

In attempt to develop a drug delivery system using serum albumin microspheres, bovine serum albumin microspheres containing antitumor agent, cytarabine, were prepared. The shape, surface characteristics, size distribution, behavior of in vitro distribution, drug release behaior, and degradation of albumin microspheres in animal liver tissue homogenate and proteolytic enzyme were investigated. The shape of albumin microspheres was spherical and the surface was smooth and compact. The size distribution of the albumin microspheres was affected by dispersion forces during emulsification and albumin concentration. Distribution of albumin mirospheres after intravenous administration in rabbit was achieved immediately. In vitro, albumin microsphere matrix was so hard that it retained most of cytarabine except initial burst during the first 10 minutes, and the level of drug release during the initial burst was affected by heating temperature, drug/albumin concentration ratio and size distribution. After drug release test, the morphology of albumin micropheres was not changed. Albumin microsphere matrix was degraded by the rabbit liver tissue homogenate and proteolytic enzyme. The degree of degradation was affected by heating temperature.