• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.37-37
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• 1996

Tenecin fragments are antimicrobial and antifungal peptide from Tenebrio molitor with highly positive charged amino acid residues. To elucidate their membrane selectivity and molecular mechanism, various forms of tenecin fragments were synthesized, and their interaction with acidic phospholipid, Gram (+), fungal and human erythrocyte membrane were investigated by ANTS/DPX leakage, membrane binding and fusion assay. (omitted)

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.572-584
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• 2002

Rapid development in molecular biology and recent advancement in recombinant technology increase identification and commercialization of potential protein drugs. Traditional forms of administrations for the peptide and protein drugs often rely on their parenteral injection, since the bioavailability of these therapeutic agents is poor when administered nonparenterally. Tremendous efforts by numerous investigators in the world have been put to improve protein formulations and as a result, a few successful formulations have been developed including sustained-release human growth hormone. For a promising protein delivery technology, efficacy and safety are the first requirement to meet. However, these systems still require periodic injection and increase the incidence of patient compliance. The development of an oral dosage form that improves the absorption of peptide and especially protein drugs is the most desirable formulation but one of the greatest challenges in the pharmaceutical field. The major barriers to developing oral formulations for peptides and proteins are metabolic enzymes and impermeable mucosal tissues in the intestine. Furthermore, chemical and conformational instability of protein drugs is not a small issue in protein pharmaceuticals. Conventional pharmaceutical approaches to address these barriers, which have been successful with traditional organic drug molecules, have not been effective for peptide and protein formulations. It is likely that effective oral formulations for peptides and proteins will remain highly compound specific. A number of innovative oral drug delivery approaches have been recently developed, including the drug entrapment within small vesicles or their passage through the intestinal paracellular pathway. This review provides a summary of the novel approaches currently in progress in the protein oral delivery followed by factors affecting protein oral absorption.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.1
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• pp.1-6
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• 2001

Silk protein has been investigated by many researchers to apply to biomedical field. We reviewed biomedical applications of silk protein such as matrix of wound dressing and drug delivery system. Since silk fibroin/ poly (ethylene glycol) (PEG) semi-interpenetrating polymer networks showed good mechanical properties and wound healing phenomena, it can be used as wound dressing materials. Sericin nanoparticles pre- pared by conjugation with PEG and silk protein/ poloxamer mixture gel are expected to become a deliv- ery as matrix for hydrophobic drug.

• Journal of Pharmaceutical Investigation
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• v.40 no.spc
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• pp.33-43
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• 2010

Hyaluronic acid (HA) is a biodegradable, biocompatible, non-toxic, non-immunogenic and non-inflammatory linear polysaccharide, which has been used for various medical applications including arthritis treatment, wound healing, ocular surgery, and tissue augmentation. Because of its mucoadhesive property and safety, HA has received much attention as a tool for drug delivery system development. It has been used as a drug delivery carrier in both nonparenteral and parenteral routes. The nonparenteral application includes the ocular and nasal delivery systems. On the other hand, its use in parenteral systems has been considered important as in the case of sustained release formulation of protein drugs through subcutaneous injection. Particles and hydrogels by various methods using HA and HA derivatives as well as by conjugation with other polymer have been the focus of many studies. Furthermore, the affinity of HA to the CD44 receptor which is overexpressed in various tumor cells makes HA an important means of cancer targeted drug delivery. Current trends and development of HA as a tool for drug delivery will be outlined in this review.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.1
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• pp.1-13
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• 2015

Despite recent progresses in nanoparticle-based drug delivery systems, there are still many unsolved limitations. Most of all, a major obstacle in current nanoparticle-based drug carrier is the lack of sufficient drug delivery into target cells due to various biological barriers, such as: extracellular matrix, endolysosomal barrier, and drug-resistance associated proteins. To circumvent these limitations, several research groups have utilized photochemical internalization (PCI), an extension of photodynamic therapy (PDT), in design of innovative and efficient nano-carriers drug delivery. This review presents an overview of a recent research on utilization of PCI in various fields including: anti-cancer therapy, protein delivery, and tissue engineering.

• Macromolecular Research
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• v.16 no.6
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• pp.481-488
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• 2008

Apoptosis is a natural cell suicide mechanism to maintain homeostasis. However, many of the diseases encountered today are caused by aberrant apoptosis where excessive apoptosis leads to neurodegenerative disorders, ischemic heart disease, autoimmune disorders, infectious diseases, etc. A variety of antiapoptotic agents have been reported to interfere with the apoptosis pathway. These agents can be potential drug candidates for the treatment or prevention of diseases caused by dysregulated apoptosis. Obviously, world-wide pharmaceutical and biotechnology companies are gearing up to develop antiapoptotic drugs with some products being commercially available. Polymeric drug delivery systems are essential to their success. Recent R&D efforts have focused on the chemical or bioconjugation of antiapoptotic proteins with the protein transduction domain (PTD) for higher cellular uptake with antibodies for specific targeting as well as with polymers to enhance the protein stability and prolonged effect with success observed both in vivo and in vitro. All these different fusion antiapoptotic proteins provide promising results for the treatment of dysregulated apoptosis diseases.

• BMB Reports
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• v.49 no.11
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• pp.585-586
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• 2016

Extracellular vesicles (EVs) are natural carriers of biomolecules that play central roles in cell-to-cell communications. Based on this, there have been various attempts to use EVs as therapeutic drug carriers. From chemical reagents to nucleic acids, various macromolecules were successfully loaded into EVs; however, loading of proteins with high molecular weight has been huddled with several problems. Purification of recombinant proteins is expensive and time consuming, and easily results in modification of proteins due to physical or chemical forces. Also, the loading efficiency of conventional methods is too low for most proteins. We have recently proposed a new method, the so-called exosomes for protein loading via optically reversible protein-protein interaction (EXPLORs), to overcome the limitations. Since EXPLORs are produced by actively loading of intracellular proteins into EVs using blue light without protein purification steps, we demonstrated that the EXPLOR technique significantly improves the loading and delivery efficiency of therapeutic proteins. In further in vitro and in vivo experiments, we demonstrate the potential of EXPLOR technology as a novel platform for biopharmaceuticals, by successful delivery of several functional proteins such as Cre recombinase, into the target cells.

• KSBB Journal
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• v.22 no.4
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• pp.213-217
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• 2007

It has been reported that hydrophobic additives generally decrease the release rate of protein drugs from drug delivery systems (DDS) and hydrophilic additives increase the release rate. In many cases, however, the addition of hydrophilic molecule is necessary for improving the stability of protein drugs. In the present work, the effects of hydrophilic additives on the release profiles, and micelle formation of protein drug formulations were investigated to develop a novel method for protein drug delivery. For model protein drug, bovine serum albumin (BSA) was employed and several hydrophilic additives were used in the release experiments. Hydrophilic additive D-sorbitol showed the lower release rates of BSA than other hydrophobic additives due to the gel strengthening ability of the additive and the optimum concentration of D-sorbitol was 3 w/v % for the retarded release rate. In addition, it was found that the addition of D-sorbitol was very effective for obtaining homogeneous and stable DDS. The results were discussed in terms of the micelle formation and the micelle structure, i.e., the differences in gel structure and the distribution of drugs in micelles.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.213-213
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• 2001

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.212-230
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• 2001

Recent advances in recombinant DNA technology have resulted in development of many new protein drugs. Due to the unique properties of protein druges, they have to be delivered by parenteral injection Although delivery of protein drugs by other routes, such as pulmonary and nasal routes, has shown some promises, to date most protein drugs are administered by par-enteral routs. For long-term delivery of protein drugs by parenteral administration, they have been formulated into biodegradable microspheres. A number of microencapsulation methods have been developed, and the currently used microencapsulation methods are reviewed here, The microen-capsulation methods have been divided based on the method used. They are: solvent evapora-tion/extraction; phase separation (coacervation);spray drying; ionotropic gelation/polyelectrolyte complexation; interfacial polyumerization and supercritical fluid precipitation. Each method is de-scribed fro its applications, advantages, and limitations.