IntroductionAptamers, single-stranded DNA or RNA sequences, fold into distinctive three-dimensional (3D) structures, enabling them to selectively recognize targets akin to monoclonal antibodies. These molecules are exclusively obtained in vitro through a process termed SELEX (S ystematic E volution of L igands byEx ponential enrichment), initially proposed independently by two research groups (1, 2). The SELEX methodology was patented in 1993 by one of its originators and remained under protection for two decades. However, in 2010, the patent expired, rendering it openly accessible to the scientific community (3).Aptamers exhibit remarkable recognition capabilities across a broad spectrum of targets, ranging from small molecules like ions, antibiotics, and dyes, to larger entities such as proteins and entire cells. This diversity in target recognition translates into a wide array of applications, typically falling into five main categories: 1) Antineoplastic agents, 2) Drugs for specific purposes, 3) Mixtures of active ingredients without chemical characterization, 4) Combinations with antibodies, and 5) Regulation of gene expression.In recent years, aptamer research has witnessed exponential growth, driven by advancements in SELEX techniques, bioinformatics, and nanotechnology. These advancements have led to the development of aptamers with enhanced specificity, stability, and binding affinity, opening new avenues for their application in various fields.For instance, aptamers have shown promising results as therapeutic agents in cancer treatment, demonstrating the potential to specifically target tumor cells while minimizing off-target effects. Additionally, aptamers have been utilized in the development of biosensors for the rapid and sensitive detection of pathogens, toxins, and biomarkers in clinical samples, food safety, and environmental monitoring.Moreover, the versatility of aptamers extends to their integration with other technologies, such as nanoparticles, to enhance drug delivery systems and imaging agents. This interdisciplinary approach has paved the way for innovative solutions in personalized medicine and targeted therapy.Distinct from conventional scientific literature and news articles, patents offer both technical specifications and insights into potential future applications. Therefore, the objective of this review is to delineate the current applications of aptamers, pinpoint the most promising avenues for commercial utilization, and deliberate on the prospective trajectories of these molecular entities. Through a comprehensive analysis of patents, scientific literature, and technological trends, this review aims to provide valuable insights into the evolving landscape of aptamer-based technologies and their impact on various fields of research and industry.

Chagas disease is caused by the Trypanosoma cruzi parasite and is transmitted by infected triatomine bugs. This infection affects approximately 8 million people in the Americas, and due to globalization and displacement, it is becoming increasingly common to find infected patients worldwide. Diagnosis of the disease in its acute form is relatively simple, as the parasite can be detected in peripheral blood smears, and symptoms are visible. However, in its chronic condition, the parasite is almost undetectable, and indirect tests are necessary to determine the presence of antibodies in infected patients. It is important to note that a single test is not enough to confirm the disease, as a second serological test should confirm the diagnosis. If the results are contradictory, a third test should be performed to solve the problem. Unfortunately, laboratories may not have access to all necessary tests in many rural areas where the disease is more frequent. Rapid tests to diagnose this disease present problems, such as significant variations in sensitivity and specificity in different countries. Therefore, searching for new biomarkers that allow for optimal correlation is essential. In this work, we have searched scientific literature from the last years for mentions of novel biomarkers for diagnosis, treatment follow-up, and prediction of cardiac complications in Chagas disease in its chronic phase.

• Bio-SELEX allows the identification of new biomarkers from biological samples. • Three steps are essential to perform Bio-SELEX; 1) Traditional SELEX, 2) Pull down, and 3) Mass spectrometry. • Bio-SELEX strategy allows the identification of biomarkers for infectious and non-infectious diseases. The SELEX strategy was discovered in 1990 by two groups of independent researchers [Tuerk and Gold 1990; Ellington and Szostak 1990]. This technique makes it possible to obtain aptamers, which are ssDNA and ssRNA molecules, which adopt unique three-dimensional (3D) structures allowing them to recognize specific targets with high affinity and specificity. Since then, the creation of multiple variations of the SELEX technique has evolved. Negative-SELEX [Ellington and Szostak 1992], Counter-SELEX [Jenison et al. 1994], Capillary electrophoresis SELEX (CE-SELEX) [Mendosa and Bowser 2004], Microfluidic-SELEX [Lou et al. 2009], Cell-SELEX [Daniels et al. 2003] are some of the variants that, based on advances in molecular biology, biomedical engineering, and biotechnology have improved the time of acquisition and the ability to recognition of the aptamers by different types of targets. Our research group has been developing a variant of the SELEX strategy that can be adaptable to multiple studies. Therefore, we report a new SELEX strategy modification to identify new biomarkers from biological samples called Bio-SELEX. The word Bio refers to the search for biomarkers and the biological nature of the samples used to obtain them.