Novel Self-Assembled Multifunctional Nanoprobes for Second-Near-Infrared-Fluorescence-Image-Guided Breast Cancer Surgery and Enhanced Radiotherapy Efficacy.

Breast-conserving surgery (BCS) is the predominant treatment approach for initial breast cancer. However, due to a lack of effective methods evaluating BCS margins, local recurrence caused by positive margins remains an issue. Accordingly, radiation therapy (RT) is a common modality in patients with advanced breast cancer. However, while RT also protects normal tissue and enhances tumor bed doses to improve therapeutic effects, current radiosensitizers cannot meet these urgent clinical needs. To address this, a novel self-assembled multifunctional nanoprobe (NP) gadolinium (Gd)-diethylenetriaminepentaacetic acid-human serum albumin (HSA)@indocyanine green-Bevacizumab (NPs-Bev) is synthesized to improve the efficacy of fluorescence-image-guided BCS and RT. Fluorescence image guidance of the second near infrared NP improves complete resection in tumor-bearing mice and accurately discriminates between benign and malignant mammary tissue in transgenic mice. Moreover, targeting tumors with NPs induces more reactive oxygen species under X-ray radiation therapy, which not only increases RT sensitivity, but also reduces tumor progression in mice. Interestingly, self-assembled NPs-Bev using HSA, the magnetic resonance contrast agent and Bevacizumab-targeting vascular growth factor A, which are clinically safe reagents, are safe in vitro and in vivo. Therefore, the novel self-assembled NPs provide a solid precision therapy platform to treat breast cancer.

Correction: Zn2SnO4:Cr,Eu ultra-small nanoparticles as new near infrared-emitting persistent luminescent nanoprobes for cellular and deep tissue imaging at 800 nm.

Correction for 'Zn2SnO4:Cr,Eu ultra-small nanoparticles as new near infrared-emitting persistent luminescent nanoprobes for cellular and deep tissue imaging at 800 nm' by Hongwu Zhang et al., Nanoscale, 2017, 9, 8631-8638.

Luminescence enhancement of CaF2:Nd3+ nanoparticles in the second near-infrared window for in vivo imaging through Y3+ doping.

In vivo luminescent imaging in the second biological window (1000-1400 nm, NIR-II) has attracted increasing attention since it can provide high sensitivity to deep tissue in vivo imaging. Herein, we synthesized approximately 10-15 nm-sized NIR-II luminescent nanoparticles (CaF2:Nd3+ NPs). Furthermore, co-doped Y3+ was utilized to enhance the NIR-II luminescence of the CaF2:Nd3+ NPs via breaking the aggregation of Nd3+. The appearance of a (200) diffraction peak and the broadening of the interplanar spacing of the (111) plane both showed that the incorporated Y3+ can dissolve in CaF2 by occupying the Ca2+ sites to form a CaF2-YF3 solid solution. In particular, the addition of Y3+ can greatly enhance the of the NIR-II luminescence of CaF2:Nd3+ NPs. When the Y3+ doped concentration reached 0.30, the luminescence intensity of CaF2:Y3+,Nd3+ NPs was about 65 times that of CaF2:Nd3+ NPs. In addition, the quantum yield of Ca0.68Y0.30Nd0.02F2.32 NPs was 9.30% under the excitation of an 808 nm laser with 483 mW cm-2 power, which was about 3 times higher than that of CaF2:Nd3+ NPs (3.10%). The in vivo imaging results revealed that the in vivo imaging intensity of Ca0.68Y0.30Nd0.02F2.32 NPs was about 2.38-fold stronger than that of Ca0.98F2.02:Nd3+ 0.02 NPs. All of these results indicated that CaF2:Y3+,Nd3+ NPs can be regarded as potential in vivo imaging probes for biological imaging.

Five-nanometer ZnSn2O4:Cr,Eu ultra-small nanoparticles as new near infrared-emitting persistent luminescent nanoprobes for cellular and deep tissue imaging at 800 nm.

Until now, the afterglow emissions of most developed near infrared (NIR)-emitting persistent luminescent nanoparticles (NPLNPs) were located at approximately 700 nm, at the edge of the first tissue transparency window (from 650 to 900 nm), which resulted in relatively low tissue penetration and signal-to-noise ratio (SNR) for in vivo imaging. Herein, 5 nm ZnSn2O4:Cr,Eu (ZSO) NPLNPs with NIR afterglow emission at 800 nm are synthesized via a direct aqueous-phase synthesis method. The longer NIR afterglow emission of ZSO NPLNPs can easily penetrate approximately 3 cm of pork tissue. Furthermore, even though the backbones blocked part of the NIR afterglow light, high SNR (25.5) in vivo images of the backs of mice can be observed and can be maintained for more than 15 min. The ZSO nanoprobes conjugated with folic acid exhibited excellent in vitro and in vivo tumor targeting capacity, which was advantageous for accurate tumor diagnosis. More importantly, the ZSO NPLNPs can be re-excited in situ and in vivo using NIR light to realize renewable near-infrared persistent luminescence in vivo, which was helpful for very long term and higher SNR in vitro and in vivo imaging.

Effect of light on toxicity of nanosilver to Tetrahymena pyriformis.

More and more silver nanoparticles (AgNPs) have been released into the aquatic environment due to their widespread use, which may result in harmful effects on aquatic organisms. Environmental risk assessments of AgNPs on aquatic organisms in the natural environment (including light, sound, etc.) are indispensable. The aim of the present study was to elucidate the influence of light on the toxicity of AgNPs to Tetrahymena pyriformis. Silver nanoparticles, which were synthesized by reduction of silver nitrate with sodium borohydride, ranged in size from 5 to 20 nm with most particles approximately 10 nm. The authors performed AgNPs toxicity assays under a simulated natural environment with sunlight. The results indicated that the toxicity of AgNPs is higher than silver ion in the environment without light, but under the light condition, the toxicity of AgNPs decreased greatly. After 24 h of incubation with AgNPs, the inhibition ratio was 69.2 ± 7% in the dark and 35.5 ± 2% in the light, and the degree of inhibition was reduced by 33.7%. However, the effect of light on Ag(+) could be negligible. Further investigation indicated that the light irradiation could induce the growth of AgNPs and sequentially form bulk agglomeration. This decreased the surface area and the number of bare Ag atoms, resulting in a slower release rate and less Ag(+) ions released from AgNPs. At the same time, bulk agglomeration induced the deposition of part of the AgNPs to the aquatic bottom, which decreased the amount of AgNPs existing in water. All these phenomena led to the weakened toxicity of AgNPs in a light irradiation environment.