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siRNA Delivery for Therapeutic Applications Using Nanoparticles
Published in Yashwant Pathak, Gene Delivery, 2022
Many metal oxide particles, especially iron oxide particles, have taken the spotlight due to their unique characteristics. In addition to the fact that these nanoparticles can be used for bio-imaging, have excellent cellular absorption, and are stable and modifiable like other metal-based nanoparticles, they have the distinguishing feature of thermal activation that is also shared with gold nanoparticles. Iron oxide particles can be used to heat the tumors to lethal temperatures, causing the coagulative necrosis of tumor cells upon the application of alternating magnetic fields. Furthermore, SPIO nanoparticles were reported to be perfect candidates for future siRNA therapies for many diseases, including lung cancer, given their strong contrast (i.e., MRI signal) and their unique magnetic properties that allow them to be guided using an external magnetic field to accumulate in the tumor sites. Magnetic targeting can improve both the delivery of siRNA and/or therapeutic compounds (i.e., chemotherapeutic drugs) to improve cancer treatment. We have previously reported that targeting of intravenously injected SPIO nanoparticles to the lung was proved to be enhanced when using external high-energy magnets positioned over a specific region of the lung. This approach was further elaborated in another study in which the use of high-energy magnets offered improved theragnostic effect of Doxorubicin-loaded iron-tagged nanocarriers, by magnetically targeting them towards metastatic tumor sites in the lungs [44–48].
Cancer Nanotheranostics
Published in Richard L. K. Glover, Daniel Nyanganyura, Rofhiwa Bridget Mulaudzi, Maluta Steven Mufamadi, Green Synthesis in Nanomedicine and Human Health, 2021
Maluta Steven Mufamadi, Marian Jiya John, Mpho Phehello Ngoepe, Palesa Rose Sekhejane
Phytonanotechnology or green bionanotechnology involves metallic nanoparticle synthesis using phytochemicals extracted from plant extracts and biomolecules as a green synthesis method. The utilized metals and/or metal oxides include silver, gold, titanium, iron, zinc, copper, zinc oxide and copper oxide (Patra and Baek, 2014; Barabadi et al., 2017; Nagajyothi et al., 2017; Umar et al., 2019). This eco-friendly biosynthetic procedure promises to offer the next generation of cancer therapy that are effective and inexpensive with minimal toxicity (Aromal and Philip, 2012; Barabadi et al., 2017; Mufamadi and Mulaudzi, 2019; Mufamadi et al., 2019). The unique structural, therapeutic and optical properties of silver and gold nanomaterials make them suitable candidates for cancer nanotheranostics applications (Pietro et al., 2016). The aim of this chapter is to understand the weaknesses and strengths of green bionanotechnology in cancer theranostics. This chapter will highlight the recent research advances related to plant-mediated synthesis of metallic nanoparticles for early detection of cancer, therapy and theranostics. This chapter will also look at the opportunities and challenges of using different plant sources as enabling tools towards the production of safer metallic nanoparticles for cancer treatment, imaging and nanotheranostics.
Interactions between Oral Bacteria and Antibacterial Polymer-Based Restorative Materials
Published in Mary Anne S. Melo, Designing Bioactive Polymeric Materials for Restorative Dentistry, 2020
Fernando L. Esteban Florez, Sharukh S. Khajotia
However, due to lower production costs and better biocompatibility properties, the large body of research available has focused on oxides of zinc and titanium as potential alternatives for the development of novel antibacterial dental biomaterials. Metal oxide nanoparticles (size average ≅25–35 nm) are typically present in cosmetic ingredients, food packaging, paints, and medical devices. In dentistry, they are present in the formulation of endodontic materials, and their accepted mechanism of action is based on the production of reactive oxygen species (ROS). Liu et al.[194] investigated the utility of ZnO nano-solutions (3, 6, and 12 mmol/l, 70 nm; Alfa Aesar, Ward Hill, USA) against Escherichia coli (O157:H7). Their findings (SEM, TEM, and Raman spectroscopy) have clearly demonstrated the establishment of a concentration-dependent mechanism where higher concentrations of nanoparticles resulted in more substantial antimicrobial properties. In regard to their mechanism of action, their findings have demonstrated that cells were grown in the presence of ZnO nanoparticles (12 mmol/l) displayed deformed cell walls, altered membrane components (lipids and proteins), disorganized intracellular structures, and leakage of intracellular components.
Algal extracellular polymeric substances (algal-EPS) for mitigating the combined toxic effects of polystyrene nanoplastics and nano-TiO2 in Chlorella sp.
Published in Nanotoxicology, 2023
Lokeshwari Natarajan, M. Annie Jenifer, Willie J. G. M. Peijnenburg, Amitava Mukherjee
The marine environment is often considered a ‘sink’ for various pollutants. The increased usage of nanomaterialsfor commercial and consumer applications has raised significant concerns regarding their effects on biological systems. Among the variousNPs, metal oxide nanomaterials can adversely affect marine biota (Xia et al. 2017; Yan et al. 2021). In particular, nano-TiO2 (P25) is known to be one of the most used materials (Chen and Selloni 2014; Khalid, Aqeel, and Noman 2020). Nano-TiO2 poses serious risk to marine organisms due to its photo-catalytic and non-biodegradable nature (Etacheri et al. 2015). The toxicity of nano-TiO2 in Chlorella pyrenoidosa was studied by Al-Ammari et al. (2021). Their findings imply that the size of the particles and their solubility are the key factors that dictate their cytotoxicity. A recent report by Baharlooeian, Kerdgari, and Shimada (2021) highlighted the negative effects of nano-TiO2 in the algal species,Chaetoceros muelleri. Metzler, Erdem, and Huang (2018) demonstrated that the deposition of nano-TiO2 on the cell surface of Raphidocelis subcapitata may block nutrient transport.
Short-term oral administration of non-porous and mesoporous silica did not induce local or systemic toxicity in mice
Published in Nanotoxicology, 2020
Joan Cabellos, Irene Gimeno-Benito, Julia Catalán, Hanna K. Lindberg, Gerard Vales, Elisabet Fernandez-Rosas, Radu Ghemis, Keld A. Jensen, Rambabu Atluri, Socorro Vázquez-Campos, Gemma Janer
Beyond local toxicity, one of the main concerns of insoluble nanoparticle exposure is the potential systemic absorption and consequent long-term accumulation. Hyperspectral imaging is a relatively new technique to assess the presence and distribution of nanomaterials in biological samples in a label-free manner, allowing minimal interference with the sample integrity, which permits its assessment with other methods later. Several studies using an hyperspectral image system have been performed to detect different type of metallic, metal oxides, and even organic NPs in a variety of tissues (Ilves et al. 2014; Husain et al. 2013; Talamini et al. 2017; Holian et al. 2019). In some studies, inductively coupled plasma mass spectrometry (ICP-MS) has been used to confirm the results of hyperspectral data (Talamini et al. 2017). In this case, measuring silicon via ICP-MS would be challenging due to the ubiquitous presence of silica in labware and the analytical equipment and the natural-occurring silicon background in tissues (Aureli et al. 2020).
The effects of nano-sized PbO on biomarkers of membrane disruption and DNA damage in a sub-chronic inhalation study on mice
Published in Nanotoxicology, 2020
Lucie Bláhová, Zuzana Nováková, Zbyněk Večeřa, Lucie Vrlíková, Bohumil Dočekal, Jana Dumková, Kamil Křůmal, Pavel Mikuška, Marcela Buchtová, Aleš Hampl, Klára Hilscherová, Luděk Bláha
Despite their toxicological relevance, studies focused on chronic inhalation of metal oxide NP are still limited. In accordance with previous sub-chronic inhalation experiments with e.g. CdO nanoparticles and also PbONP (Bláhová et al. 2014; Dumkova et al. 2016; Dumková et al. 2017; Lebedová et al. 2018, 2016), the present study confirmed nanoparticles (in agglomerated form) in all studied organs at the end of the experiment. The observed accumulation of Pb in the lung was fast, it reached a plateau after 2 weeks and did not further increase up to 13 weeks, which corresponds to observations from a previous study that also included acute exposures to PbONP (Lebedová et al. 2018). The highest levels of Pb were observed in the lung and kidney, followed by the liver. Fast distribution to all tissues after the start of the exposure, mediated most likely by the blood transport, has also been reported for other metal oxide NP (Blum et al. 2012; Lebedová et al. 2016; Takenaka et al. 2004). Interestingly, a different pattern was observed for the brain, where Pb concentrations significantly increased during the exposure, which suggests differences in distribution mechanisms. In addition to blood transport, direct transfer of NP along the nasal nerve to the olfactory bulbs and to the brain could also play a role. A comparable delay in the peak of TiO2 concentration in the brain (compared to other organs) has also been observed in other NP inhalation studies involving rats (Pujalté et al. 2017; Wang et al. 2008).