Abstract
In this report, lanthanum strontium manganite at different Sr
2+
ion concentrations, as well as Gd
3+
or Sm
3+
ion substituted La
0.5−
Y
M
Y
Sr
0.5
MnO
3
(M = Gd and Sm,
y
= 0.2), have been purposefully tailored using a sol gel auto-combustion approach. XRD profiles confirmed the formation of a monoclinic perovskite phase. FE-SEM analysis displayed a spherical-like structure of the La
0.8
Sr
0.2
MnO
3
and La
0.3
Gd
0.2
Sr
0.2
MnO
3
samples. The particle size of the LSM samples was found to decrease with increased Sr
2+
ion concentration. For the first time, different LSM concentrations were inspected for their cytotoxic activity against CACO-2 (intestinal carcinoma cells) and HepG-2 (human hepatocellular carcinoma cells). The cell viability for CACO-2 and HepG-2 was assayed and seen to decrease depending on the Sr
2+
ion concentration. Half maximal inhibitory concentration IC
50
of CACO-2 cell and HepG-2 cell inhibition was connected with Sr
2+
ion ratio. Low IC
50
was noticable at low Sr
2+
ion content. Such results were correlated to the particle size and the morphology. Indeed, the IC
50
of CACO-2 cell inhibition by LSM at a strontium content of 0.2 was 5.63 ± 0.42 µg/mL, and the value increased with increased Sr
2+
ion concentration by up to 0.8 to be = 25 ± 2.7 µg/mL. Meanwhile, the IC
50
of HepG-2 cell inhibition by LSM at a strontium content of 0.2 was 6.73 ± 0.4 µg/mL, and the value increased with increased Sr
2+
ion concentration by up to 0.8 to be 31± 3.1 µg/mL. All LSM samples at different conditions were tested as antimicrobial agents towards fungi, Gram positive bacteria, and Gram negative bacteria. For instance, all LSM samples were found to be active towards Gram negative bacteria Escherichia coli, whereas some samples have presumed antimicrobial effect towards Gram negative bacteria Proteus vulgaris. Such results confirmed that LSM samples possessed cytotoxicity against CACO-2 and HepG-2 cells, and they could be considered to play a substantial role in pharmaceutical and therapeutic applications.