- 著者
- Hossain Md. Amran Ikeda Yutaka Hara Toru Nagasaki Yukio
- 出版者
- Elsevier
- 雑誌
- Colloids and surfaces. B, Biointerfaces (ISSN:09277765)
- 巻号頁・発行日
- vol.102, pp.778-782, 2013-02
- 被引用文献数
- 7 3
A new approach to the preparation of PEGylated [PEG: poly(ethylene glycol)] SiO2/Au hybrid nanoparticles was investigated. The synthesis of a PEGylated nanogel containing SiO2/Au hybrid nanoparticles was performed using matrix-catalyzed hydrolysis of tetraethyl orthosilicate, followed by the reduction of HAuCl4. UV–vis absorption of the prepared hybrid particles was obtained at 618 nm, which is a much longer wavelength than that of a nanogel containing only Au nanoparticles (523 nm). High-angle annular dark field images of the prepared particles observed using transmission electron microscopy and energy-dispersive X-ray spectroscopy confirmed the coexistence of Si and Au in the same particle. The presence of Si and Au in the prepared particles was also confirmed by inductively coupled plasma atomic emission spectroscopy. Dynamic light-scattering measurements of the particles in a highly ionic medium showed that they have high stability in both acidic and basic regions.
- 著者
- Yuan Xiaofei Fabregat Dolça Yoshimoto Keitaro Nagasaki Yukio
- 出版者
- Elsevier
- 雑誌
- Colloids and surfaces. B, Biointerfaces (ISSN:09277765)
- 巻号頁・発行日
- vol.99, pp.45-52, 2012-11
- 被引用文献数
- 23
Rabbit anti-human ferritin (anti-hFT) polyclonal immunoglobulin G (IgG) and poly(ethylene glycol) (PEG) were sequentially co-immobilized onto polystyrene submicroparticles (sMPs) to construct sMP/anti-hFT/PEG (SAP) immunolatex. Chemical immobilization of anti-hFT was performed at different pH levels to evaluate variations in antigen recognition. Basic pH disfavored conjugation of anti-hFT to sMPs, but remarkably increased its antigen recognition in comparison to that at neutral pH. We investigated this intriguing phenomenon further by assessing the kinetics of antibody binding, including the time-dependency of immobilization, antigen recognition, and orientation of bound anti-hFT. Therefore, we attributed high antigen recognition to significant electrostatic repulsion between sMPs and anti-hFT at basic pH, which predominately prevented anti-hFT access to sMPs and concurrently promoted anti-hFT orientations suitable for antigen recognition. Subsequent PEG modification maintained such anti-hFT orientation, without which antigen-accessible orientations would have decreased with time. Thus, properly oriented antibody and immediate PEGylation after antibody immobilization contributed to the formation of a high-performance SAP immunolatex.