Surface functionalized nanoparticles: A boon to biomedical science.

The rapid development of nanomedicine has increased the likelihood that manufactured nanoparticles will one day come into contact with people and the environment. A variety of academic fields, including engineering and the health sciences, have taken a keen interest in the development of nanotechnology. Any significant development in nanomaterial-based applications would depend on the production of functionalized nanoparticles, which are believed to have the potential to be used in fields like pharmaceutical and biomedical sciences. The functionalization of nanoparticles with particular recognition chemical moieties does result in multifunctional nanoparticles with greater efficacy while at the same time minimising adverse effects, according to early clinical studies. This is because of traits like aggressive cellular uptake and focused localization in tumours. To advance this field of inquiry, chemical procedures must be developed that reliably attach chemical moieties to nanoparticles. The structure-function relationship of these functionalized nanoparticles has been extensively studied as a result of the discovery of several chemical processes for the synthesis of functionalized nanoparticles specifically for drug delivery, cancer therapy, diagnostics, tissue engineering, and molecular biology. Because of the growing understanding of how to functionalize nanoparticles and the continued work of innovative scientists to expand this technology, it is anticipated that functionalized nanoparticles will play an important role in the aforementioned domains. As a result, the goal of this study is to familiarise readers with nanoparticles, to explain functionalization techniques that have already been developed, and to examine potential applications for nanoparticles in the biomedical sciences. This review's information is essential for the safe and broad use of functionalized nanoparticles, particularly in the biomedical sector.

Correction: 3T1R model and tuning of thermoluminescence intensity by optimization of dopant concentration in monoclinic Gd2O3:Er3+;Yb3+ co-doped phosphor.

Correction for '3T1R model and tuning of thermoluminescence intensity by optimization of dopant concentration in monoclinic Gd2O3:Er3+;Yb3+ co-doped phosphor' by Raunak Kumar Tamrakar et al., Phys. Chem. Chem. Phys., 2017, 19, 14680-14694.

3T1R model and tuning of thermoluminescence intensity by optimization of dopant concentration in monoclinic Gd2O3:Er3+;Yb3+ co-doped phosphor.

Thermoluminescence property of a phosphor is an important parameter that helps to determine the use of a phosphor in various dosimetric applications. In this study, the thermoluminescence behaviour of a monoclinic Gd2O3:Er3+;Yb3+ nanophosphor was studied. Gd2O3:Er3+;Yb3+ nanophosphor was prepared using a combustion synthesis method. Structural characterization was carried out via X-ray diffraction and electron microscopy methods. Herein, thermoluminescence (TL) study and kinetic analysis of the UV- and gamma-irradiated phosphor was also carried out. The prepared phosphor exhibits two TL glow curves around 122 and 263 °C for UV excitation and 157 and 295 °C for gamma exposure. The effect of different parameters on the TL glow curve was investigated. The glow curve deconvolution function was applied on the tuned glow peak curve. The trapping parameters were determined for tuned glow curve peaks as well as for the deconvoluted peaks. Moreover, reproducibility of the sample was determined via 7 replicate TL measurements. The prepared sample shows good reproducibility for both UV and gamma exposure. A theoretical three trap and one recombination centre (3T1R) model was proposed to explain the concentration quenching effect on the thermoluminescence behaviour of the prepared sample.

Structural characterization of Er(3+),Yb(3+)-doped Gd2O3 phosphor, synthesized using the solid-state reaction method, and its luminescence behavior.

We report the synthesis and structural characterization of Er(3+),Yb(3+)-doped Gd2O3 phosphor. The sample was prepared using the conventional solid-state reaction method, which is the most suitable method for large-scale production. The prepared phosphor sample was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermoluminescence (TL), photoluminescence (PL) and CIE techniques. For PL studies, the excitation and emission spectra of Gd2O3 phosphor doped with Er(3+) and Yb(3+) were recorded. The excitation spectrum was recorded at a wavelength of 551 nm and showed an intense peak at 276 nm. The emission spectrum was recorded at 276 nm excitation and showed peaks in all blue, green and red regions, which indicate that the prepared phosphor may act as a single host for white light-emitting diode (WLED) applications, as verified by International de I'Eclairage (CIE) techniques. From the XRD data, the calculated average crystallite size of Er(3+) and Yb(3+) -doped Gd2O3 phosphor is ~ 38 nm. A TL study was carried out for the phosphor using UV irradiation. The TL glow curve was recorded for UV, beta and gamma irradiations, and the kinetic parameters were also calculated. In addition, the trap parameters of the prepared phosphor were also studied using computerized glow curve deconvolution (CGCD).

Effect of annealing on down-conversion properties of monoclinic Gd2O3:Er3+ nanophosphors.

Erbium-doped nano-sized Gd2O3 phosphor was prepared by a solution combustion method in the presence of urea as a fuel. The phosphor was characterized by X-ray diffractometry (XRD), Fourier transform infra-red spectroscopy, energy dispersive X-ray analysis (EDX) and transmission electron microscopy (TEM). The results of the XRD shows that the phosphor has a monoclinic phase, which was further confirmed by the TEM results. Particle size was calculated by the Debye-Scherrer formula. The erbium-doped Gd2O3 nanophosphor was revealed to have good down-conversion (DC) properties and the intensity of phosphor could be modified by annealing. The effects of annealing at 900°C on the particle size and luminescence properties were studied and compared with freshly prepared Gd2O3:Er(3+) nanoparticles. The average particle sizes were calculated as 8 and 20 nm for the freshly prepared samples and samples annealed at 900°C for 1 h, respectively. The results show that both freshly prepared and annealed Gd2O3:Er(3+) have monoclinic structure.