• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1713-1719
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• 2006

A method for the simple, rapid, specific, and accurate detection of Bacillus anthracis spores was developed by employing specific capture peptides conjugated with fluorescent quantum dots (QDs). It was possible to distinguish B. anthracis spores from the spores of B. thuringiensis and B. cereus using these peptide-QD conjugates by flow cytometric and confocal laser scanning microscopic analyses. For more convenient high-throughput detection of B. anthracis spores, spectrofluorometric analysis of spore-peptide-QD conjugates was performed. B. anthracis spores could be detected in less than 1 h using this method. In order to avoid any minor yet false-positive signal caused by the presence of B. thuringiensis spores, the B-Negative peptide, which can only bind to B. thuringiensis, conjugated with another type of QD that fluoresces at different wavelength was also developed. In the presence of mixed B. anthracis and B. thuringiensis spores, the BABA peptide conjugated with QD525 and the B-Negative peptide conjugated with QD585 were able to bind to the former and the latter, specifically and respectively, thus allowing the clear detection of B. anthracis spores against B. thuringiensis spores by using two QD-labeling systems. This capture peptide-conjugated QD system should be useful for the detection of B. anthracis spores.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.1
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• pp.46-52
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• 2015

Herein we present the synthesis of $^{68}Ga$-labeled gold nanoparticles for in vivo PET imaging. A novel chelator DTPA-Cys was easily prepared from diethylenetriaminepentaacetic dianhydride in high yield. The ${\alpha}_v{\beta}_3$ integrin receptor targeted gold nanoparticle probe was synthesized by using DTPA-Cys, polyethylene glycol and cRGD peptide. $^{68}Ga$ labeling of cRGD conjugated gold nanoparticle was carried out at $40^{\circ}C$ for 30 min. Observed radiochemical yield was more than 75% as determined by radio-TLC and the probe was purified by centrifugation. In vitro stability test showed that 90% of $^{68}Ga$-labeled gold nanoparticle probe was stable in FBS for 1 h. Those results demonstrated that $^{68}Ga$-labeled gold nanoparticle could be used as a potentially useful probe for specific tumor imaging.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.84-84
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• 2013

FcBP consisting of 13 amino acids specifically binds to Immunoglobulin G Fc domain. Initially, we utilized this peptide for preparation of antibody chip as a PEG composite for enhanced solubility. After then, the peptide conjugate was immobilized on agarose resin, resulting in highly efficient affinity column for antibody purification. The efficiency was comparable to commercial Protein A column. Recently, this peptide was conjugated with cell penetratingpeptide (CPP) on a backbone of GFP, affording antibody transducer, which carries antibody into live cells by simple mixing of antibody and the transducer in cell culture media. Antibody transduction into cells was monitored by live cell imaging. More recently, the FcBP was fused to ferritin cage, which consists of 24 ferritin protein molecules. The FcBP-ferritin cage showed greatly increased binding affinity to human IgG. Its binding was analyzed by QCM and SPR analysis. Finally, it was selectively delivered by Herceptin to SKBR3, a breast cancer cell, over MCF10A, non-tumorigenic cells.

• KSBB Journal
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• v.24 no.1
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• pp.80-88
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• 2009

Human prostatic acid phosphatase (PAP), with comprehensive homology to glandular kallikrein, are representative serum biomarkers of prostate cancer. Dendritic cell (DC), which is the potent antigen-presenting cells(APC) in the immune system, can induce strong T cell responses against viruses, microbial pathogens, and tumors. Therefore, the immunization using DC loaded with tumor-associated antigens is a powerful method for inducing anti-tumor immunity. The CTP (Cytoplasmic Transduction Peptide) technology developed by Creagene which can transport attached bio-polymers like nucleic acids or proteins into the cell with high permeation efficiency. As the active forms of PAP can mediate apoptotic processing, we used multimer forms of PAP as an inactive form for antigen pulsing of DCs. In this study, multimeric forms of CTP-rhPAP was obtained according to the advanced purification process and subsequently confirmed by gel filtration chromatography, western blot and Dynamic Light Scattering. Therefore, CTP-conjugated PA multimers transduced into the cytoplasm were efficiently presented on the cell surface without any harm effect on cells via MHC class I molecules and result in induction of a large number of effector cell.