Monitoring Proteolytic Activity in Real Time: A New World of Opportunities for Biosensors

Abstract

Proteases play a pivotal role in several biological processes, from digestion, cell proliferation, and differentiation to fertility. Deregulation of protease metabolism can result in several pathological conditions (i.e., cancer, neurodegenerative disorders, and others). Therefore, monitoring proteolytic activity in real time could have a fundamental role in the early diagnosis of these diseases. Herein, the main approaches used to develop biosensors for monitoring proteolytic activity are reviewed. A comparison of the advantages and disadvantages of each approach is provided along with a discussion of their importance and promising opportunities for the early diagnosis of severe diseases. This new era of biosensors can be characterized by the ability to control and monitor biological processes, ultimately improving the potential of personalized medicine. Biosensing in Personalized Medicine: The Emergence of Protease BiomarkersA deep understanding of the individual characteristics of biological processes and precise control of responses and feedback to therapies are essential in a world that is running towards personalized medicine (see Glossary). Recent reports predict that this market will grow at a compound annual growth rate (CAGR) of over 11% from US$92.4 billion dollars in 2017 to US$194.4 billion in 2024 (https://www.researchandmarkets.com/research/n5kqz7/global?w=5), with oncology responsible for 30% of the revenues generated. Biosensors are one of the underlying technologies of personalized medicine, giving support to the highly informed decisions that are critical to obtain better clinical outcomes and to decrease undesired side-effects. Compared with the personalized medicine market, a similar tendency is observed for the biosensors market where growth from US$18.6 billion dollars in 2018 to US$31.5 billion in 2025 (8% CAGR) is expected (https://www.gminsights.com/industry-analysis/biosensors-market).One of the primary goals of a biosensor is to determine the presence/absence or activity of a given biomarker and to correlate these results with pathophysiological conditions. Proteases are emerging as a new category among the wide variety of biomarkers targeted by biosensors due to their key role in health and disease. In this review, we present the main approaches used to measure proteolytic activity in real timefor both in vivo and in vitro applicationsand discuss recent developments in and future possibilities for protease biosensors (Figure 1A). The Roles and Idiosyncrasies of Proteases: Why Monitor Proteolytic Activity?Proteases are a widely explored research topic as illustrated by more than 487 000 entries registered in PUBMED. However, it was only recently that proteases emerged as an analyte of interest for biosensing [68]. These hydrolytic enzymes (EC 3.4) play a pivotal role in several biological processes, such as digestion, cell proliferation, and differentiation [1], as well as apoptosis [2], coagulation [3], immunity [4], and fertility [5]. The deregulation of protease metabolism can resul...

The Tumor Proteolytic Landscape: A Challenging Frontier in Cancer Diagnosis and Therapy

“…Exploration of the protease landscape associated with cancer has enabled the emergence of promising clinical technologies exploiting pathologic patterns of proteolytic activity for diagnosis and therapy ( Table 2 ). Engineering toolsets for incorporating protease responsiveness are more readily available than ever, with the potential to be integrated into nanosystems that empower the next generation of protease-based diagnostic and therapeutic modalities [ 342 ]. Protease research has already greatly benefited from interdisciplinary connections of molecular biology and biomedicine with nanotechnology, polymer chemistry, and microfluidics.…”

Carbon Dots-Based Logic Gates

“…With the current pandemic situation, the development of smart medicine will be very helpful. There are some reports available that discuss one of the strategies to fight the outbreak of COVID 19 is the real-time monitoring of proteolytic activity with potential protease inhibitors as biosensors for COVID 19 [ 75 ]. In one of the reports, COVID 19 genome was used as the input for an AND logic function.…”

Fluorescence for biological logic gates

“…It is still very difficult to detect the disease, not to mention the current lack of direct treatment. Research has already discussed the applicability of smart chemical detection systems for COVID-19 [18], and researchers are developing various biological stimulusdriven mechanisms to aid in the effort against the disease. Logic gate-like devices offer an ideal tool to effectively treat such a new, fast-spreading, and hard-to-detect pandemic, and also such well-known conditions as cancer that still pose great challenges worldwide.…”

“…The concept of biological logic gates did not start overnight, and there are many papers related to the field. Several reviews explore the concept of stimuli-responsive nanoparticles, which are able to provide more efficient and specific drug delivery based on biomolecules or enzymes present in certain medically relevant situations [3,11,[15][16][17][18], and there are also reviews on such smart devices based on DNA origami [19]. Some reviews discuss fluorescent probes activated by certain biological conditions [20][21][22][23], and other reviews explicitly refer to logic devices or operations [8,9,12,14].…”