Monitoring Tyrosinase Expression in Non‐metastatic and Metastatic Melanoma Tissues by Scanning Electrochemical Microscopy

Abstract

Although tremendous progress has been made in the diagnosis of melanoma, the identification of different stages of malignancy in ar eliable wayr emains challenging.C urrent strategies rely on optical monitoring of the concentration and spatial distribution of specific biomarkers.S tate-of-the-art optical methods can be affected by background-color interference and autofluorescence.W eo vercame these shortcomings by employings canning electrochemical microscopy( SECM) to map the prognostic indicator tyrosinase (TyR) in nonmetastatic and metastatic melanoma tissues by using soft-stylus microelectrodes.E lectrochemical readout of the TyRd istribution was enabled by adapting an immunochemical method. SECM can overcome the limitations of optical methods and opens unprecedented possibilities for improved diagnosis and understanding of the spatial distribution of TyRi nd ifferent melanoma stages.

Mapping the antioxidant activity of apple peels with soft probe scanning electrochemical microscopy

“…This still needs to be confirmed in the future, but it can be suggested that the present feedback mode approach recognizes in part the global AO activity that is able to reduce FcMeOH + . The pressure that is exerted by the soft probe onto the substrate is rather small as previously demonstrated by melanoma tissues and self-assembled monolayers that were brushed without detectable damage [55,56]. In this work, we have recorded a video sequence of a soft probe sliding along the vertical cross-section of an apple peel, including a lenticel area, in order to identify a possible deformation and compression of the apple peel (SI-8).…”

“…The common goal of most constant distance SECM approaches and related techniques is the improvement of the imaging resolution to the nanoscale, mainly by reducing the probe dimensions [49,[52][53][54]. However, the typical micrometer resolution of standard SECM probes is still sufficient for many biological samples, such as tissues, where the analysis of relatively large areas exceeding square millimeters is required [55].…”

“…In this work, we employed soft SECM probes that are made of thin and flexible polymeric materials with an implemented carbon microelectrode enabling gentle contact mode scanning over delicate samples, i.e., soft probe scanning electrochemical microscopy [55,56]. Such scanners are ideal for measurements on the fragile and curved peel of apples (Scheme 1).…”

Recent Advances in Scanning Electrochemical Microscopy for Biological Applications

“…TyR is a vital enzyme that controls the production of melanin, and can be used as a highly selective indicator to monitor melanoma stages [98]. SECM was proposed for precisely mapping the TyR distribution in melanoma tissues [99]. To solve the swelling problem of the tissue and improve the measurement resolution in the use of a conventional Pt microelectrode, a soft-stylus probe was designed to conduct line scans over skin biopsy sections containing (1) normal; (2) melanoma stage II; and (3) melanoma stage III skin tissues.…”

Biomarkers in Malignant Melanoma: Recent Trends and Critical Perspective

“…Alternatively, determination of tyrosinase as a tissue biomarker also has been taken into account. In this regard, Lin et al very recently presented a novel methodology using scanning electrochemical microscopy for mapping expression and distribution of the Type 3 copper protein tyrosinase in tissue microarrays of skin biopsies taken from melanoma patients (14). Interestingly, the progression from a homogeneous tyrosinase distribution in Stage II to a more heterogeneous pattern in Stage III was clearly visualized.…”