Recent advances in nanomaterial-based biosensors for testosterone detection

The detection of steroid hormones is crucial due to their significant impact on human health and physiological activity. Among these, detection of testosterone is particularly important as both its deficiency and excess in our body are associated with various diseases. Given that the levels of testosterone are typically in the pg mL^-1 range, highly sensitive and efficient biosensor platforms are required. Nanomaterials have played a major role in improving both the sensitivity and specificity of such sensors. In this review, we summarise all reported biosensors related to testosterone that incorporate different types of nanomaterials (from carbon and metal sources). The detection methods mainly include optical and electrochemical, owing to their rapid response and user-friendly operation. The classification of the biosensors is primarily based on the receptor materials used, where nanomaterials play a vital role. The efficiency, detection limit, and advantages or limitations of each work are discussed. Further, the future perspective of the developed methods for on-site detection in the form of point-of-care (POC) devices is discussed. This review provides researchers a comprehensive overview and up-to-date findings to guide future advancements in testosterone biosensing.