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Quantum Dots as Biointeractive and Non-Agglomerated Nanoscale Fillers for Dental Resins
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Isadora Martini Garcia, Fabrício Mezzomo Collares
Quantum dots have broad applicability in vitro and in vivo. As shown in Figure 10.5, the properties of quantum dots, such as their fluorescence, may be a promising strategy for many purposes. In health sciences, quantum dots have been used as biomarkers due to their feature of intermittent luminescence. These nanoparticles are so small that their radius is smaller than the gap between the valence band and electron position in the conduction band when a bulk semiconductor material is excited. When this gap, also called as “exciton Bohr radius,” is higher than the particle radius, electrons and holes (in the vacancy band) undergo quantum confinement and are not free to move (Bimberg and Pohl 2011), making the particle stable if controlled from the external environment.
A Pilot Study in Non-Human Primates Shows No Adverse Response to Intravenous Injection of Quantum Dots
Published in Lajos P. Balogh, Nano-Enabled Medical Applications, 2020
Ling Ye, Ken-Tye Yong, Liwei Liu, Indrajit Roy, Rui Hu, Jing Zha, Hongxing Cai, Wing-Cheung Law, Jianwei Liu, Kai Wang, Jing Liu, Yaqian Liu, Yazhuo Hu, Xihe Zhang, Mark T. Swihart, Paras N. Prasad
Quantum dots have been used in biomedical research for imaging [1, 2], diagnostics [3, 4] and sensing purposes [5, 6]. However, concerns over the cytotoxicity of their heavy metal constituents [7, 8] and conflicting results from in vitro [7, 9] and small animal [10–14] toxicity studies have limited their translation towards clinical applications. Here, we show in a pilot study that rhesus macaques injected with phospholipid micelle-encapsulated CdSe/CdS/ZnS quantum dots do not exhibit evidence of toxicity. Blood and biochemical markers remained within normal ranges following treatment, and histology of major organs after 90 days showed no abnormalities. Our results show that acute toxicity of these quantum dots in vivo can be minimal. However, chemical analysis revealed that most of the initial dose of cadmium remained in the liver, spleen and kidneys after 90 days. This means that the breakdown and clearance of quantum dots is quite slow, suggesting that longer-term studies will be required to determine the ultimate fate of these heavy metals and the impact of their persistence in primates.
Innovations and Future Prospects of Dermal Delivery Systems
Published in Tapash K. Ghosh, Dermal Drug Delivery, 2020
Rashmi Upasani, Anushree Herwadkar, Neha Singh, Ajay K. Banga
Quantum dots are nanostructures made of semiconductor materials having unique optical and electronic properties. Research studies have revealed their ability to permeate through the stratum corneum of human skin equivalent models (EpidermTM). Their ability to accumulate in the epidermis may have implications on transdermal delivery upon long-term dermal exposure (Jeong et al. 2010).
Folate functionalized pH-sensitive photothermal therapy traceable hollow mesoporous silica nanoparticles as a targeted drug carrier to improve the antitumor effect of doxorubicin in the hepatoma cell line SMMC-7721
Published in Drug Delivery, 2020
Yue Cao, Chao Wu, Ying Liu, Lili Hu, Wenjing Shang, Zhanshan Gao, Nan Xia
With the development of cancer diagnosis and treatment technologies, quantum dots have been widely used as biomarkers. Commonly used quantum dots include CdTe quantum dots (Shi et al., 2014), CdSe quantum dots (Li et al., 2019), and carbon quantum dots (CQDs) (Kim et al., 2013), etc. Among them, CQDs have good water solubility, excellent biocompatibility, and light stability. At the same time, these quantum dots have great potential in the field of bioimaging (Zhou et al., 2013; Hu et al., 2014), so they are very suitable as a tracer material. To further improve the targeting effect of nanoparticles, targeted ligands such as carrier modifiers have been widely investigated. Common target ligands include folic acid (FA), chitosan, ferritin (Federici et al., 2016; Fracasso et al., 2016), iodinated hyaluronic acid, etc. Among them, FA has high affinity with folate receptors (FRs). Since FRs are overexpressed in liver cancer cells (Elnakat & Ratnam, 2006; Maeng et al., 2010), FA is an ideal target for targeting liver cancer.
Preparation of liposomal doxorubicin-graphene nanosheet and evaluation of its in vitro anti-cancer effects
Published in Journal of Liposome Research, 2019
Samira Tajvar, Soheila Mohammadi, Alireza Askari, Sajjad Janfaza, Maryam Nikkhah, Elnaz Tamjid, Saman Hosseinkhani
The tracking of anti-cancer agents, upon their administration, can play an important role to formulate effective anti-cancer therapeutics. Quantum dots have various applications in biological research such as labeling, particle tracking, multi-coloured and multi-modal imaging especially in tumours and drug delivery (Zhu et al. 2013, Samadikhah et al. 2016). The main disadvantage of colloidal semiconductor quantum dots is their inherent toxicity (Shen et al. 2012). Graphene quantum dots (GQDs), a new generation of quantum dots, are little pieces of graphene sheets that demonstrate very low toxicity and are soluble in various solvents. Considering their special characteristics, such as light absorption and photoluminescence, GQDs have the potential to be used in bioimaging, tracking, photodynamic and photothermal therapy (Singh et al. 2011, Shen et al. 2012, Li et al. 2013, 2016, Yang et al. 2013, Bacon et al. 2014). Dong et al. treated human breast cancer MCF-7 cells with green emitting GQDs and indicated that GQDs were able to label the cell membrane, the cytoplasm, and the nucleus simultaneously. Gao et al. reported a GO-based fluorescent magnetic hybrid for delivery of Dox into hepatocellular carcinoma cell line. They used GO for in vitro imaging and showed high cellular uptake of the hybrid system (Gao et al. 2013). Xu et al. have been summarized several researches on imaging by GQDs (Xu et al. 2013).
Pharmaceutical potential of quantum dots
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Swati Jha, Prateek Mathur, Suman Ramteke, Narendra Kumar Jain
Quantum dots are currently limited to cell and small animal uses due to its probable long term in vivo toxicity and degradation. Optical imaging is highly sensitive, quantitative, capable of multiplexing and is significantly cheaper as compared to the traditional imaging modalities such as MRI and positron emission tomography that will substantially reduce the cost and shorten the time involved in new drug development. Therefore, for nano-carrier development and optimization, QDs can become an excellent “prototype” from which biocompatible carriers of similar sizes and surface properties could be made for clinical uses. Current applications of QDs in drug delivery are focused on two major areas: using QDs as carriers, and labelling therapeutics or drug carriers with QDs [11–15].