Figure 3.

Mechanism of and use for point-of-care, smartphone- and colorimetric-paper-based semen analysis

(A) The mechanism of color change of yellow MTT into purple formazan used to assess mitochondria content in sperm.

(B) Potential applications of the MTT test strip, which can be used either at home, at clinics, or in resource-limited developing countries. Upon collecting a semen sample, men can easily determine results using a smartphone or color indicator chart (within 15 min).

Adapted from ref. (Tsao et al., 2020) in accordance with the Creative Commons 4.0 International (CC BY 4.0) license.