A borondipyrrolemethene-based turn-on fluorescent probe for silver ion with high sensitivity and selectivity and its application in water samples and living cells

•A BODIPY compound is synthesized and used as a fluorescent probe for Ag+.•It shows high sensitive response toward Ag+ with a 40-fold fluorescence enhancement.•The detection limit can reach 0.02M, which complies with the standard of WHO.•The probe exhibits high selective detection of Ag+ over other metal ions.•The probe is applied in real water samples and living cells successfully.