**3. Future prospects and challenges**

In recent years, the development of biosensors for biomarkers for breast cancer has received a lot of attention. However, the developments of biomarkers and the innovation of diagnostic tools for early detection of breast cancer are still in their early stages. While electrochemical immunoassays were very successful bio transducers, biomarkers established for breast cancer are needed to test their specificity, responsiveness and efficiency against the diagnostic standards created. The production and progression of these advanced cancer screening systems will aid in the early stages of accelerated clinical cancer diagnoses. Nonetheless, proposed detection approaches for biomarker detection of cancer necessarily require standardization of pre- and post-analytical protocols such as sample preparation, storage and optimization of experimental conditions for true validity of assays and more genuine output of the biosensor produced. Although very low LODs have been obtained by electrochemical biosensors, they typically convey multi-step mark strategies that complicate the experimental activity. For future works, the development another problem is that owing to its low accuracy and reliability, few portable electrochemical instruments are in clinical usage. Therefore, robust biosensor-based POC devices are required of ultrasensitive electrochemical label-free methods will be a great potential. Researchers must train the electrochemical biosensor to solve their reliability problems with a significant number of clinical samples. The development of wireless micro/nano electrochemical biosensors is an ideal option for in vivo

detection, as they can work in an invasively style. The approachable properties of electrochemical instruments improve the performance of cancer diagnostics and therapy monitoring. With further advancement and funding, these handheld instruments are anticipated to improve cancer diagnosis, rendering diagnostic findings accessible in a matter of minutes at the patient bedside or practitioner's office.
