Insights into Terminal Sterilization Processes of Nanoparticles for Biomedical Applications

Abstract

Nanoparticles possess a huge potential to be employed in numerous biomedical purposes; their applications may include drug delivery systems, gene therapy, and tissue engineering. However, the in vivo use in biomedical applications requires that nanoparticles exhibit sterility. Thus, diverse sterilization techniques have been developed to remove or destroy microbial contamination. The main sterilization methods include sterile filtration, autoclaving, ionizing radiation, and nonionizing radiation. Nonetheless, the sterilization processes can alter the stability, zeta potential, average particle size, and polydispersity index of diverse types of nanoparticles, depending on their composition. Thus, these methods may produce unwanted effects on the nanoparticles’ characteristics, affecting their safety and efficacy. Moreover, each sterilization method possesses advantages and drawbacks; thus, the suitable method’s choice depends on diverse factors such as the formulation’s characteristics, batch volume, available methods, and desired application. In this article, we describe the current sterilization methods of nanoparticles. Moreover, we discuss the advantages and drawbacks of these methods, pointing out the changes in nanoparticles’ biological and physicochemical characteristics after sterilization. Our main objective was to offer a comprehensive overview of terminal sterilization processes of nanoparticles for biomedical applications.

Growth-Promoting Gold Nanoparticles Decrease Stress Responses in Arabidopsis Seedlings

“…Since contaminants in plant growth media allow for the growth of microorganisms, NPs need to be sterile before their use in plant assays. As shown by previous studies, autoclaving and radiation sterilization might result in the aggregation of the NPs, loss of the coating, and contamination with potential microbial toxins [129][130][131][132][133]. Sterile filtration has been shown not to directly affect the physical properties of NPs, but filter materials should be tested to exclude possible interactions with particle surfaces resulting in NP retention or coating removal [132].…”

“…As shown by previous studies, autoclaving and radiation sterilization might result in the aggregation of the NPs, loss of the coating, and contamination with potential microbial toxins [129][130][131][132][133]. Sterile filtration has been shown not to directly affect the physical properties of NPs, but filter materials should be tested to exclude possible interactions with particle surfaces resulting in NP retention or coating removal [132]. We tested CME and PES filters and revealed that PES filters are suitable for sterilization of AuNPs, whereas CME filtering resulted in a significant reduction in the number of NPs in the filtered samples.…”

Impact of Sterilization on the Colloidal Stability of Ligand-Free Gold Nanoparticles for Biomedical Applications

“…There are several methods available for sterilization of NPs, including sterile filtration, steam sterilization (also called autoclaving or moist sterilization), and ionizing and nonionizing radiations. , For instance, ionizing radiation such as γ- or X-rays induces significant direct damage to microorganisms and causes microbial death primarily due to energy deposition on the vital components such as enzymes or DNA. , In addition to this, chemical routes such as treatments with gas plasma, formaldehyde, and ethylene oxide , could also be applied, although these procedures are difficult to use on colloidal systems. Vetten et al compared the impact of different sterilization methods on NPs.…”

Investigation of the Antibacterial and Antibiofilm Activity of Selenium Nanoparticles against Vibrio cholerae as a Potent Therapeutics

“…In this study to investigation of sterility of prepared nanoparticles, SeNPs were cultured on the following media, including thioglycolate media, nutrient agar, blood agar, MacConkey agar, and Sabouraud dextrose agar, and then placed under anaerobic and aerobic conditions. The optimal culture period was also examined [ 17 ].…”