Nanoparticles, especially gold nanoparticles (Au NPs) have gained increasing interest in biomedical applications. Used for disease prevention, diagnosis and therapies, its significant advantages in therapeutic efficacy and safety have been the main target of interest. Its application in immune system prevention, stability in physiological environments and cell membranes, low toxicity and optimal bioperformances are critical to the success of engineered nanomaterials. Its unique optical properties are great attractors. Recently, several physical and chemical methods for coating these NPs have been widely used. Biomolecules such as DNA, RNA, peptides, antibodies, proteins, carbohydrates and biopolymers, among others, have been widely used in coatings of Au NPs for various biomedical applications, thus increasing their biocompatibility while maintaining their biological functions. This review mainly presents a general and representative view of the different types of coatings and Au NP functionalization using various biomolecules, strategies and functionalization mechanisms.

Background: This study is a systematic review with meta-analysis comparing radioactive seed localization (RSL) versus radio-guided occult lesion localization (ROLL) and wire-guided localization (WGL) for patients with impalpable breast cancer undergoing breast-conserving surgery and evaluating efficacy, safety, and logistical outcomes. The protocol is registered in PROSPERO with the number CRD42022299726. Methods: A search was conducted in the Embase, Lilacs, Pubmed, Scielo, Web of Science, and clinicaltrials.gov databases, in addition to a manual search in the reference list of relevant articles, for randomized clinical trials and cohort studies. Studies selected were submitted to their own data extraction forms and risk of bias analysis according to the ROB 2 and ROBINS 1 tools. A meta-analysis was performed, considering the random effect model, calculating the relative risk or the mean difference for dichotomous or continuous data, respectively. The quality of the evidence generated was analyzed by outcome according to the GRADE tool. Overall, 46 articles met the inclusion criteria and were included in this systematic review; of these, 4 studies compared RSL and ROLL with a population of 1550 women, and 43 compared RSL and WGL with a population of 19,820 women. Results: The results showed that RSL is a superior method to WGL in terms of surgical efficiency in the impalpable breast lesions’ intraoperative localization, and it is at least equivalent to ROLL. Regarding security, RSL obtained results equivalent to the already established technique, the WGL. In addition to presenting promising results, RSL has been proven to be superior to WGL and ROLL technologies.

New forms of cancer treatment, which are effective, have simple manufacturing processes, and easily transportable, are of the utmost necessity. In this work, a methodology for the synthesis of radioactive Gold-198 nanoparticles without the use of surfactants was described. The nuclear activated Gold-198 foils were transformed into H¹⁹⁸AuCl₄ by dissolution using aqua regia, following a set of steps in a specially designed leak-tight setup. Gold-198 nanoparticles were synthesized using a citrate reduction stabilized with PEG. In addition, TEM results for the non-radioactive product presented an average size of 11.0 nm. The DLS and results for the radioactive ¹⁹⁸AuNPs presented an average size of 8.7 nm. Moreover, the DLS results for the PEG-¹⁹⁸AuNPs presented a 32.6 nm average size. Cell line tests showed no cytotoxic effect in any period and the concentrations were evaluated. Furthermore, in vivo testing showed a high biological uptake in the tumor and a cancer growth arrest.

Background: The radioactive seed localization (RSL) is used in impalpable breast cancer conservative surgery to assist the surgeon in accurately locating and excising the lesion site. This study aims to present recommendations about the RSL program implementation in health institutions that perform breast cancer conservative surgery with intraoperative localization. Methods: An extensive literature review was performed. It comprehends: the committee responsible for implementation of the program actions; description of the necessary multidisciplinary team; the radiological safety committee role; the facility licensing; professionals training; material and instrumentation associated with the technique; and seed tracking system. Results: 13 topics are presented. The Program Implementation Committee must be formed by leaders from each department. The committee assumes responsibility for evaluating the necessary processes and presenting the schedule for program implementation. Since the procedure is classified as a nuclear medicine procedure it requires licensing. The Professional Team Formation, Education, and Training is a priority and simulation exercises are necessary. The Materials and Instrumentation Associated with the Technique must be well-know by the team and they should practice using radiation detectors. The seed must be always tracked, from moment they are received to discard. An Inventory for Tracking Seeds is provided. The Radiological Safety Aspects such as the ALARA principle are presented. A full description for the Radiological Procedure for Placing the seeds, the surgical removal and the Specimen Handling in Pathology focusing on how to locate the seed and retrieve them. After removed, the seeds can be placed in storage to wait for full radioactive decay or be returned to the manufacturer. Conclusions: The procedure has the advantage to increase to 2 months the time between insertion of the seed and the surgical removal. Regular multidisciplinary team meetings during program development are important to create a realistic timeline, having briefing meetings after the first 1-5 RSL cases and having annual or biannual follow-up meetings to discuss any issues or incidents. Highlights: