• Journal of Pharmaceutical Investigation
• /
• v.26 no.2
• /
• pp.125-135
• /
• 1996

Solid lipid nanoparticles(SLN) are particulate systems for parenteral drug administration and suitable for controlled release. SLN were prepared by homogenization process. Dispersion at increased temperature (molten lipid) was performed to yield SLN loaded with lipophilic drugs. Tetracaine base, lidocaine base, prednisolone, methyltestosterone and ethinylestradiol were used as model drugs to access the loading capacity and to study the release behavior. To investigate production parameters(lipids, surfactant concentration, homogenizing rpm) in the formation of SLN, particle size was performed by laser diffraction analysis. The mean particle size of SLN with stearic acid or trilaurin was below 1 micron. By decreasing the particle size and increasing the surfactant concentration, the release rate was increased especially in the case of highly lipophilic drug loaded SLN. Methyltestosterone or ethinylestradiol loaded SLN showed a distinctly prolonged release over a few days.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.33 no.4
• /
• pp.219-225
• /
• 2007

Bis-ethylhexyloxyphenolmethoxyphenyltrizine (BEMT) is one of the most widely used chemical UVA+UVB double absorbers in sunscreen products. But topical application of BEMT is restricted due to its defects in product. The purpose of this study is to adopt the sunscreen product of solid lipid nano-particles containing BEMT (BEMT-SLN). The particle diameters, the encapsulation efficiencies and the crystallization index (C.I.) are about 330nm, 93.3 % and the 4.3 %. As a result, in vitro penetration and release of BEMT were generally higher in O/W emulsion than the SLN formulation. However in vivo study, it was shown that the rate of release could be decreased by 80 % in the SLN formulation. The sun protection factor (SPF) of the SLN formulation increased by 100 % in the in vitro UV protection test. Therefore, SLN formulation potentiated the UV-blocking power of BEMT. This study suggest that SLN can be used for the encapsulation of BEMT.

• KSBB Journal
• /
• v.19 no.3
• /
• pp.178-186
• /
• 2004

The aim of this study was to investigate the skin-whitening effect of okyong-san and to develop new drug delivery carrier The extracts of okyong-san were found to have the whitening effect and Eudragit$\^$ⓡ/ L 100-55 (EUD) coated solid lipid nanoparticle (E-SLN) was prepared by solvent evaporation method and melt dispersion technique. As a result, E-SLN have a 144-170 nm of particle size, spherical shape, and 33-41% encapsulation efficiency, After release test in vitro, release profile of E-SLN depended on pH and temperature. Lastly, closed patch test and skin-whitening test was peformed clinically. In conclusion, test sample had non-stimulation and high % whiteness. The results suggest that okyong-san and E-SLN is useful as cosmeceuticals for whitening cosmetics.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.3
• /
• pp.1481-1488
• /
• 2014

Background: To avoid performing axillary lymph node dissection (ALND) for non-sentinel lymph node (SLN)-negative patients with-SLN positive axilla, nomograms for predicting the status have been developed in many centers. We created a new nomogram predicting non-SLN metastasis in SLN-positive patients with invasive breast cancer and evaluated 14 existing breast cancer models in our patient group. Materials and Methods: Two hundred and thirty seven invasive breast cancer patients with SLN metastases who underwent ALND were included in the study. Based on independent predictive factors for non-SLN metastasis identified by logistic regression analysis, we developed a new nomogram. Receiver operating characteristics (ROC) curves for the models were created and the areas under the curves (AUC) were computed. Results: In a multivariate analysis, tumor size, presence of lymphovascular invasion, extranodal extension of SLN, large size of metastatic SLN, the number of negative SLNs, and multifocality were found to be independent predictive factors for non-SLN metastasis. The AUC was found to be 0.87, and calibration was good for the present Ondokuz Mayis nomogram. Among the 14 validated models, the MSKCC, Stanford, Turkish, MD Anderson, MOU (Masaryk), Ljubljana, and DEU models yielded excellent AUC values of > 0.80. Conclusions: We present a new model to predict the likelihood of non-SLN metastasis. Each clinic should determine and use the most suitable nomogram or should create their own nomograms for the prediction of non- SLN metastasis.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.655-659
• /
• 2003

Solid lipid nanoparticle (SLN) system has been attracted increasing attention during last few years as a potential drug delivery carrier However, the SLN have disadvantage of low encapsulation efficiency for hydrophilic drug. In this study, for increase it's encapsulation efficiency, we prepared the $Eudragit^{\circledR}$ L100-55 (eudragit) coated SLN(E-SLN) based on solvent evaporation method and melt dispersion technique, and analyzed their physicochemical properties in terms of particle size, morphology, and encapsulation efficiency. As a result, they have a ${\pm}150$ nm particle size, spherical shape, and $10^{\sim}25$ % loading efficiency. SLN consists of coconut oil as core material, ascorbic acid and okyong-san as hydrophilic drug.

• Journal of Dairy Science and Biotechnology
• /
• v.25 no.2
• /
• pp.5-10
• /
• 2007

Ultrasonication was employed to prepare solid lipid nanoparticles (SLN) for smart probiotic nanoparticles as a nanofood. The model probiotic material, lactocin from Lactobacillus plantarum (CBT-LP2), was incorporated into SLN. The CBT-LP2 loaded SLN (CBT-LP2-SLN) were spherical in the photograph of scanning electron microscope (SEM). The particle size measured by laser diffraction (LD) was found to be $97.3{\pm}8.2nm$. Zeta potential analyzer suggested the zeta potential of LP-SLN was $-29.36{\pm}3.68$ mV in distilled water. The entrapment efficiency (EE%) was determined with the sephadex gel chromatogram and high-performance liquid chromatogram (HPLC), and up to 90.59% of nanofood was incorporated. Stability evaluation showed relatively long-term stability with only slight particle growth (P>0.05) after storage at room temperature for 4 weeks. Therefore, ultrasonication is demonstrated to be a simple, available and effective method to prepare high quality SLN loaded probiotic material.

• Archives of Pharmacal Research
• /
• v.26 no.12
• /
• pp.1096-1101
• /
• 2003

To enhance the liver targeting and reduce the side effects of 5-fluorouracil (5-Fu), it was acylated by stearyl chloride to obtain .$\b{N}_{\b{1}}$stearyl-5-Fu (5-FuS). The chemical structure of the prodrug was confirmed by Nuclear Magnetic Resonance and Infrared Spectrometry. 5-FuS was incorporated into solid lipid nanoparticles (SLN), which were prepared by the physical agglomeration method. The mean diameter of 5-FuS-SLN was 240.19 nm and the drug loading was 20.53%. The release characteristics in vitro of 5-FuS-SLN were fitted to the first-order pharmacokinetic model. Compared with 5-Fu injection, a study on the distribution of 5-FuS-SLN in mice showed that 5-FuS-SLN could double 5-Fu concentration in mice livers. The main pharmacokinetic parameters of 5-FuS-SLN in rabbits is shown as follows: $V_d$=0.04336L/kg, $T_{1/2} \beta$=1.2834h, CL=0.1632 L/h. In conclusion, 5-FuS-SLN has significant liver targeting properties. The employment of a prodrug to enhance drug liposoluble properties and the preparation method presented in this paper, seem to be an alternative strategy to the traditional colloidal delivery system.

• Macromolecular Research
• /
• v.16 no.8
• /
• pp.682-685
• /
• 2008

The aim of this work was to develop and evaluate solid lipid nanoparticles (SLN) containing all-trans-retinoic acid (ATRA) for topical delivery. SLN composed of coconut oil and curdlan improved the suspension instability of ATRA in aqueous solution. The photodegradation of ATRA by light was reduced by incorporation in SLN. The loading efficiency of ATRA in SLN was higher than 95% (w/w). The amounts of ATRA released from SLN at $4^{\circ}C$ and at $37^{\circ}C$ were less than 15% and more than 60% (w/w) for 96 h, respectively. The ATRA-loaded SLN can be used as a potential carrier for topical delivery.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.248.1-248.1
• /
• 2003

Keloids are characterized by abnormal proliferation of fibroblasts and overproduction of collagen. Recently, it is reported that transforming growth factor beta (TGFb) and its signaling molecule, SMAD3 are related to the mitogenic effect of fibroblasts and a stimulatory factor for collagen synthesis. Cationic SLN was developed to improve the complex formation of DNA/SLN and enhance the uptake efficiency to cells. SLN was formulated by DC-Chol, DOPE, trimyristin as a solid core and other surfactant. The physical properties of the SLN and the ATS-SLN complex were characterized. (omitted)

• Journal of Pharmaceutical Investigation
• /
• v.26 no.4
• /
• pp.245-256
• /
• 1996

Solid lipid nanoparticles (SLN) have been developed as a new drug delivery system. Although many particulate drug carriers, such as microsphere, liposome, niosome, emulsion, etc. have been introduced, they have some disadvantage; low efficiency of incorporation and stability, lack of reproducibility, and so on. Meanwhile, SLN as a new drug delivery system is known to entrap rugs with a high efficiency and a good reproducibility. Moreover, small size SLN can circulate in blood for a prolonged time. Although many preparation methods were introduced, microfluidization method is recommended to be the most useful. This study was attempted to prepare and evaluate ketoprofen-incorporated SLNs (keto-SLN), which were prepared by two methods, ultrasonication and microfluidization. Keto-SLN was evaluated by measurement of particle size and zeta potential, efficacy of entrapment, sedimentation volume, in virto release pattern. The mean particle size was about $0.1\;{\mu}m$, and the size was dependent on the type and the amount of emulsifier. Zeta potential was negative, $-9{\sim}-13mV$ and entrapment efficacy was very high and stability was good for at least 60 days in the respect of particle size and sedimentation volume ratio. Analgesic effect was also determined as well as pharmacokinetic parameters. The former was comparable to that of that of ketoprofen loaded suspension (keto-sus) and the latter revealed that consistent with the delayed release of keto-SLN. $T_{max}$ was longer than keto-sus. Therefore, keto-SLN was favourable dosage forms in the field of drug delivery system such as anti-cancer, analgesics and anti-inflammatory agents.