PNIPAM 형성이 금 나노 입자 담지 나노 젤의 제작에 미치는 영향

폰사왓 바이페이와드(Phornsawat Baipaywad),박예은(Ye-eun Park),김윤경(Yunkyung Kim),박한수(Hansoo Park) 한국고분자학회 2016 폴리머 Vol.40 No.4

금 나노 입자(AuNPs)는 바이오센서와 유전자 또는 단백질의 전달 등 많은 생물의학적 응용분야에 적용이 다양하게 연구되고 있으며 최근에 기능성 부여하고 안정성을 증가시키기 위해 고분자 복합체 연구가 활발히 진행되어 왔다. 이 연구에서, 우리는 다양한 공량체를 기반으로 하는 poly(N-isopropylacrylamide)(PNIPAM) 기반의 나노 젤을 제작하고 AuNPs는 상이한 pH 값 조건 하에서 HAuCl4의 환원에 의해 나노 젤에 담지 하였으며 공단량체에 따른 PNIPAM의 형성이 AuNPs 담지 나노 젤의 제작에 미치는 영향을 연구하였다. AuNPs 담지 나노 젤은 주사전자현미경(TEM)을 통해 그 형태를 관찰하였고, 동적광산란법(DLS), 자외-가시광분광법(UV-Vis)으로 크기 및 흡수강도를 측정하였다. Gold nanoparticles (AuNPs) have been investigated for various biomedical applications such as biosensors and genes or proteins delivery. Recently, they were modified with peptides or incorporated with polymers to increase cell penetration, specificity to targets, and stability in aqueous medium. In this study, we prepared poly(N-isopropylacrylamide) (PNIPAM) based nanogels systems containing AuNPs and examined the effect of PNIPAM formulation on the formation of AuNPs encapsulated in nanogels by using different comonomers. AuNPs were embedded into nanogels through the reduction of HAuCl4 at different pHs after PNIPAM-based nanogels were formed by a conventional radical polymerization. The morphology characterized by transmission electron microscopy (TEM) confirmed multiple non-aggregated AuNPs in PNIPAM based nanogels. Dynamic light scattering (DLS) showed the size of nanogels containing AuNPs changed with temperature and pH. UV-Vis measurements exhibited different intensity depending on PNIPAM formulations, since different amounts of gold nanoparticles were embedded in nanogels.

Skin Penetration-Inducing Gelatin Methacryloyl Nanogels for Transdermal Macromolecule Delivery

Kim, Jeehye,Gauvin, Robert,Yoon, Hee Jeong,Kim, Jin-Hoi,Kwon, Sang-Mo,Park, Hyun Jin,Baek, Sang Hong,Cha, Jae Min,Bae, Hojae The Polymer Society of Korea 2016 Macromolecular Research Vol.24 No.12

In this study, the suitability of gelatin methacryloyl (GelMA) nanogels for transdermal delivery of macromolecules was demonstrated. The synthesis of GelMA nanogels (GNs) and fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) loaded GelMA nanogels (FGNs) were implemented when confined in water-in-oil nanoemulsion droplets via the photopolymerization of the methacryloyl substituents to create crosslinked nanogels. Both GNs and FGNs existed as fine particles in aqueous condition (pH 7.4) for 7 days. No distinct aggregation of nanogel particles were observed. In the MTT assay, high percentage of cell viability indicated that GNs did not exhibit any growth inhibitory effect or significant cytotoxicity. The skin penetration study results showed that FGNs permeated across the epidermis and into the dermis of a porcine model when compared to the FITC-BSA dissolved in PBS. Possible penetration routes of FITC-BSA through the stratum corneum (SC) were illustrated by visualizing the SC structure with fluorescent signals of FITC-BSA. The penetration mechanism of FGNs across the SC layer was successfully demonstrated by explaining three penetration routes (intercellular, follicular, and transcellular route). The results suggest that GNs have a potential as a transdermal delivery carrier for hydrophilic macromolecules.

Functional poly(L-lysine) derivative nanogels with acidic pH-pulsed antitumor drug release properties

이민지,이은성,오남묵,오경택,윤유석 한국약제학회 2014 Journal of Pharmaceutical Investigation Vol.44 No.5

We developed novel poly(L-lysine) [poly(Lys)]derivative nanogels with smart drug release properties. Poly(Lys) derivative was prepared after the chemicalreaction of poly(Lys) and 3-diethylaminopropyl isothiocyanate(DEAP), and was coupled with poly(ethyleneglycol) (PEG). The obtained poly(Lys-DEAP)-b-PEG wascrosslinked by genipin (crosslinking agent) in an oil/wateremulsion condition, producing poly(Lys) derivative nanogels. These nanogels (*95 nm in diameter, pH 7.4)showed volume expansion (*200 nm in diameter) in theendosomal pH (*pH 6.0) due to extensive protonabsorption of DEAP moieties in the crosslinked nanogelcore. These nanogels reversibly swelled at pH 6.0 andshrank at pH 7.4, correspond to maximized drug release atpH 6.0 and minimized drug release at pH 7.4. We concludethat this nanogel system will have great potential for tumortherapy.

Self-organized Pullulan/Deoxycholic Acid Nanogels: Physicochemical Characterization and Anti-cancer Drug-releasing Behavior

Na, Kun,Park, Kyong-Mi,Jo, Eun-Ae,Lee, Kwan-Shik The Korean Society for Biotechnology and Bioengine 2006 Biotechnology and Bioprocess Engineering Vol.11 No.3

The objective of this study was to develop new self-organized nanogels as a means of drug delivery in patients with cancer. Pullulan (PUL) and deoxycholic acid (DOCA) were conjugated through an ester linkage between the hydroxyl group in PUL and the carboxyl group in DOCA. Three types of PUL/DOCA conjugates were obtained, differing in the number of DOCA substitutions (DS; 5, 8, or 11) per 100 PUL anhydroglucose units. The physicochemical properties of the resulting nanogels were characterized by dynamic light scattering, transmission electron microscopy, and fluorescence spectroscopy. The mean diameter of DS 11 was the smallest (approx. 100 nm), and the size distribution was unimodal. To determine the organizing behavior of these conjugates, we calculated their critical aggregation concentrations (CACs) in a 0.01-M phosphate buffered saline solution. They were $10.5{\times}10^{-4}mg/mL,\;7.2{\times}10^{-4} mg/mL,\;and\;5.6{\times}10^{-4} mg/mL$ for DS 5, 8, and 11, respectively. This indicates that DOCA can serve as a hydrophobic moiety to create self-organized nanogels. To monitor the drug-releasing behavior of these nanogels, we loaded doxorubicin (DOX) onto the conjugates. The DOX-loading efficiency increased with the degree of DOCA substitution. The release rates of DOX from PUL/DOCA nanogels varied inversely with the DS. We concluded that the PUL/DOCA nanogel has some potential for use as an anticancer drug carrier because of its low CAC and satisfactory drug-loading capacity.

The Age of Multistimuli-responsive Nanogels: The Finest Evolved Nano Delivery System in Biomedical Sciences

Sayan Basak 한국생물공학회 2020 Biotechnology and Bioprocess Engineering Vol.25 No.5

Multistimuli-Responsive Nanogels are one of the most trending materials in the scope of biomedical science, which responds when excited with a range of stimuli including temperature, pH, UV light, and redox chemical moieties. These ‘smart’ nanomaterials are reported to exhibit not only higher drug/cargo release profiles, but also enhance the specificity of target delivery. This perspective aims to circumscribe the Author’s viewpoint of how these Multistimuli-Responsive Nanogels are gradually evolving and metamorphosing the biomedical sector (drug delivery, tissue engineering, gene delivery, bio-sensors, bioimaging, cell culture systems, and bio-inspired operations) with supplements from the fascinating developments in the realms of material science and nanotechnology.

Target-specific intracellular delivery of siRNA using degradable hyaluronic acid nanogels

Lee, H.,Mok, H.,Lee, S.,Oh, Y.K.,Park, T.G. Elsevier Science Publishers 2007 Journal of controlled release Vol.119 No.2

Novel hyaluronic acid (HA) nanogels physically encapsulating small interfering RNA (siRNA) were fabricated by an inverse water-in-oil emulsion method. Thiol-conjugated HA dissolved in aqueous emulsion droplets was ultrasonically crosslinked via the formation of disulfide linkages to produce HA nanogels with a size distribution from 200 to 500 nm. Green fluorescence protein (GFP) siRNA was physically entrapped within the HA nanogels during the emulsion/crosslinking process. The HA/siRNA nanogels were readily taken up by HA receptor positive cells (HCT-116 cells) having HA-specific CD44 receptors on the surface. Release rates of siRNA from the HA nanogels could be modulated by changing the concentration of glutathione (GSH) in the buffer solution, indicating that the degradation/erosion of disulfide crosslinked HA nanogels, triggered by an intracellular reductive agent, controlled the release pattern of siRNA. When HA nanogels containing GFP siRNA were co-transfected with GFP plasmid/Lipofectamine to HCT-116 cells, a significant extent of GFP gene silencing was observed in both serum and non-serum conditions. The gene silencing effect was reduced in the presence of free HA in the transfection medium, revealing that HA nanogels were selectively taken up by HCT-116 cells via receptor mediated endocytosis.

Enhanced antibacterial activity of tilmicosin against Staphylococcus aureus small colony variants by chitosan oligosaccharide-sodium carboxymethyl cellulose composite nanogels

Wanhe Luo,Jinhuan Liu,Shanling Zhang,Wei Song,Samah Attia Algharib,Wei Chen 대한수의학회 2022 Journal of Veterinary Science Vol.23 No.1

Background: The poor bioadhesion capacity of tilmicosin resulting in treatment failure for Staphylococcus aureus small colony variants (SASCVs) mastitis. Objectives: This study aimed to increase the bioadhesion capacity of tilmicosin for the SASCVs strain and improve the antibacterial effect of tilmicosin against cow mastitis caused by the SASCVs strain. Methods: Tilmicosin-loaded chitosan oligosaccharide (COS)-sodium carboxymethyl cellulose (CMC) composite nanogels were formulated by an electrostatic interaction between COS (positive charge) and CMC (negative charge) using sodium tripolyphosphate (TPP) (ionic crosslinkers). The formation mechanism, structural characteristics, bioadhesion, and antibacterial activity of tilmicosin composite nanogels were studied systematically. Results: The optimized formulation was comprised of 50 mg/mL (COS), 32 mg/mL (CMC), and 0.25 mg/mL (TPP). The size, encapsulation efficiency, loading capacity, polydispersity index, and zeta potential of the optimized tilmicosin composite nanogels were 357.4 ± 2.6 nm, 65.4 ± 0.4%, 21.9 ± 0.4%, 0.11 ± 0.01, and -37.1 ± 0.4 mV, respectively; the sedimentation rate was one. Scanning electron microscopy showed that tilmicosin might be incorporated in nano-sized crosslinked polymeric networks. Moreover, adhesive studies suggested that tilmicosin composite nanogels could enhance the bioadhesion capacity of tilmicosin for the SASCVs strain. The inhibition zone of native tilmicosin, tilmicosin standard, and tilmicosin composite nanogels were 2.13 ± 0.07, 3.35 ± 0.11, and 1.46 ± 0.04 cm, respectively. The minimum inhibitory concentration of native tilmicosin, tilmicosin standard, and tilmicosin composite nanogels against the SASCVs strain were 2, 1, and 1 μg/mL, respectively. The in vitro time-killing curves showed that the tilmicosin composite nanogels increased the antibacterial activity against the SASCVs strain. Conclusions: This study provides a potential strategy for developing tilmicosin composite nanogels to treat cow mastitis caused by the SASCVs strain.

Dioxadet-loaded nanogels as a potential formulation for glioblastoma treatment

Roman Voeikov,Tatiana Abakumova,Nadezhda Grinenko,Pavel Melnikov,Vladimir Bespalov,Alexander Stukov,Vladimir Chekhonin,Natalia Klyachko,Natalia Nukolova 한국약제학회 2017 Journal of Pharmaceutical Investigation Vol.47 No.1

Glioblastoma multiforme is a fast-growing malignant brain tumor with poor prognosis and low survival rate. Here we investigated the potential use of anticancer drug dioxadet loaded into nanogels for glioma treatment. We used block copolymer of polyethylene glycol and polymethacrylic acid for synthesis of dioxadet carriers and two types of cross-linking agents: non-degradable ethylenediamine and biodegradable cystamine, containing disulfide bond. We analyzed physicochemical properties of nanoparticles, their loading capacity, cytotoxicity of drug-loaded nanogels, and also their internalization into glioma cells. We found the optimal conditions that promote the efficient loading of the drug. We demonstrated that dioxadet loaded nanogels have relatively high level of loading capacity (>35% w/w) and loading efficiency (>75%). We shown that nanogels with the biodegradable cross-links prone to dissociate under reducing conditions (glutathione) that allow to decrease IC50 values of the drug compared to the nanogels with ethylendiamine cross-links. This stimuli-sensitive behavior of nanogels could be beneficial for tumor treatment. Confocal analysis of glioma cells demonstrated that both types of nanogels accumulate in cells and localize in lysosomes. These results indicate that loading of dioxadet into nanoparticles can improve its performance; such formulation has a potential for further studies and practical applications.

Antibacterial activity of enrofloxacin loaded gelatin-sodium alginate composite nanogels against intracellular Staphylococcus aureus small colony variants

Luo, Wanhe,Liu, Jinhuan,Algharib, Samah Attia,Chen, Wei The Korean Society of Veterinary Science 2022 Journal of Veterinary Science Vol.23 No.3

Background: The poor intracellular concentration of enrofloxacin might lead to treatment failure of cow mastitis caused by Staphylococcus aureus small colony variants (SASCVs). Objectives: In this study, enrofloxacin composite nanogels were developed to increase the intracellular therapeutic drug concentrations and enhance the efficacy of enrofloxacin against cow mastitis caused by intracellular SASCVs. Methods: Enrofloxacin composite nanogels were formulated by an electrostatic interaction between gelatin (positive charge) and sodium alginate (SA; negative charge) with the help of CaCl₂ (ionic crosslinkers) and optimized by a single factor test using the particle diameter, zeta potential (ZP), polydispersity index (PDI), loading capacity (LC), and encapsulation efficiency (EE) as indexes. The formation mechanism, structural characteristics, bioadhesion ability, cellular uptake, and the antibacterial activity of the enrofloxacin composite nanogels against intracellular SASCVs strain were studied systematically. Results: The optimized formulation was comprised of 10 mg/mL (gelatin), 5 mg/mL (SA), and 0.25 mg/mL (CaCl₂). The size, LC, EE, PDI, and ZP of the optimized enrofloxacin composite nanogels were 323.2 ± 4.3 nm, 15.4% ± 0.2%, 69.6% ± 1.3%, 0.11 ± 0.02, and -34.4 ± 0.8 mV, respectively. Transmission electron microscopy showed that the enrofloxacin composite nanogels were spherical with a smooth surface and good particle size distributions. In addition, the enrofloxacin composite nanogels could enhance the bioadhesion capacity of enrofloxacin for the SASCVs strain by adhesive studies. The minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration, and minimum biofilm eradication concentration were 2, 4, 4, and 8 ㎍/mL, respectively. The killing rate curve had a concentration-dependent bactericidal effect as increasing drug concentrations induced swifter and more radical killing effects. Conclusions: This study provides a good tendency for developing enrofloxacin composite nanogels for treating cow mastitis caused by intracellular SASCVs and other intracellular bacterial infections.

Antibiofilm activity of polyethylene glycol-quercetin nanoparticles-loaded gelatin-N,O-carboxymethyl chitosan composite nanogels against Staphylococcus epidermidis

Wanhe Luo,Yongtao Jiang,Jinhuan Liu,Beibei Sun,Xiuge Gao,Samah Attia Algharib,Dawei Guo,Jie Wei,Yurong Wei The Korean Society of Veterinary Science 2024 Journal of Veterinary Science Vol.25 No.2

Background: Biofilms, such as those from Staphylococcus epidermidis, are generally insensitive to traditional antimicrobial agents, making it difficult to inhibit their formation. Although quercetin has excellent antibiofilm effects, its clinical applications are limited by the lack of sustained and targeted release at the site of S. epidermidis infection. Objectives: Polyethylene glycol-quercetin nanoparticles (PQ-NPs)-loaded gelatin-N,O-carboxymethyl chitosan (N,O-CMCS) composite nanogels were prepared and assessed for the on-demand release potential for reducing S. epidermidis biofilm formation. Methods: The formation mechanism, physicochemical characterization, and antibiofilm activity of PQ-nanogels against S. epidermidis were studied. Results: Physicochemical characterization confirmed that PQ-nanogels had been prepared by the electrostatic interactions between gelatin and N,O-CMCS with sodium tripolyphosphate. The PQ-nanogels exhibited obvious pH and gelatinase-responsive to achieve on-demand release in the micro-environment (pH 5.5 and gelatinase) of S. epidermidis. In addition, PQ-nanogels had excellent antibiofilm activity, and the potential antibiofilm mechanism may enhance its antibiofilm activity by reducing its relative biofilm formation, surface hydrophobicity, exopolysaccharides production, and eDNA production. Conclusions: This study will guide the development of the dual responsiveness (pH and gelatinase) of nanogels to achieve on-demand release for reducing S. epidermidis biofilm formation.