Gyubin Noh completed his Bachelor course from Keimyung University, College of Pharmacy, Daegu, Republic of Korea on February, 2016. He started MS-PhD course at College of Pharmacy, Keimyung University, Daegu, Republic of Korea from September 2016 to till date. He is now studying in 3rd semester. He is interested on transdermal drug delivery, biopharmaceutical delivery, microneedle etc
The objective of this work was to evaluate the combined effect of microneedle and iontophoresis on transdermal recombinant human growth hormone(rhGH) delivery. rhGH was used as a model macromolecule. Methylene blue staining, stereomicroscope and SEM imaging were used to characterize the microchannels. The effect of molecular charge on transdermal delivery was evaluated by permeation study in two different buffer – PBS (pH 7.4) and citrate (pH 4.0). Since hGH is negatively charged at pH 7.4 and positively charged at pH 4.0, cathodal and anodal iontophoresis was applied respectively. And the effect of current density was evaluated in three different electrical densities of 0.125, 0.25 and 0.5mA/cm2. With the optimized iontophoresis protocol, permeation studies were performed to evaluate combination effect of iontophoretic delivery through microchannels under three different settings : (a) iontophoresis alone, (b) microneedle pretreatment, (c) microneedle pretreatment with iontophoresis. The cumulative amount permeated and flux in all experiments reached a plateau in 1 hour. Anodal iontophoresis in citrate buffer showed about 10-fold higher flux of rhGH compared to cathodal iontophoresis in PBS. Also anodal iontophoresis with current density of 0.5mA/cm2 showed the 2.32 and 1.11-fold higher flux compared to 0.125 and 0.25mA/cm2 respectively. And compared to microneedle pretreatment and optimized iontophoresis alone, the combination of iontophoresis with microneedle showed 5.82 and 6.33-fold higher flux respectively. The result suggrest that anodal iontophoresis with higher current density enhance permeation of macromolecule through microchannels created by microneedles. In conclusion, combination of iontophoresis and microneedle is potential strategy for enhancing transdermal delivery of macromolecule..
Rakesh Bastola has completed his bachelor’s degree in Pharmaceutical Sciences (B. Pharm.) from Pokhara University, Nepal. He has been awarded with University Topper Medal by Nepal Pharmaceutical Association, Nepal and Dean’s List Award by Faculty of Science and Technology, Pokhara University. He is currently doing his M.S. in Pharmaceutics in Keimyung University, Republic of Korea under the scholarship program known as “Korean Government Scholarship Program.” He is working under the supervision and guidance of Prof. Sangkil Lee. He has published 1 paper in reputed journal.
High pressure homogenization including microfluidization and phase inversion are manufacturing methods used for preparing emulsions. But our study mainly focused on the development of o/w emulsions with simple self-emulsifying process that requires only stirring without the use of sophisticated equipments. Adjuvanticity of emulsions were assessed with Mycoplasma hypopneumoniae antigen. The ratio of Span® 80 and Cremophor® ELP was fixed at 7:13 and pseudo-ternary phase diagram was prepared to identify the self-emulsifying region. 3%, 5% and 10% squalene emulsions were prepared with deionized water. Furthermore, 0.01% (w/v) and 0.02% (w/v) carbomer solutions of C-971P NF and C-940 grades were also used to prepare emulsions. Altogether 15 emulsions were chosen and characterized by measuring particle size and zeta potential. Toxicity and immune response studies were done in BALB/c mice and blood samples of mice were tested for Mycoplasma hypopneumoniae-specific antibody titers. In our study, most of the emulsions exhibited droplet size in submicron size range and maintained throughout the period of 3 months. Majority of them maintained zeta potential values between -40mV to 0 mV. Emulsions could maintain their homogeneity upon gentle shaking. They showed no toxic effects and their immunogenic responses were good enough to compare with positive control-Montanide ISATM 201. Acknowledgements: This research was supported by Technology Development Program (Project No. 316093-2 and Project No. 316094-2) for Bio-industry, Ministry for Agriculture, Food and Rural Affairs, Republic of Korea.