In this report Micro-structural, magnetic, electronic, and magneto-transport properties of perovskite Pr0.7Sr0.3MnO3 manganite nanoparticles have been thoroughly investigated. A series of samples with different particle size (Φ) is synthesized by chemical pyrophoric reaction process. Rietveld refinement of X-Ray diffraction pattern of the sample showed single phase orthorhombic structure with Pbnm space group. Metal- insulator transition () has been observed in the temperature range of 180-200 K in zero field resistivity data (2300 K) and it differs from ferromagnetic to paramagnetic transition temperature () due to enhanced surface disorder effect. The lowest nanomentric sample exhibit maximum 85 % magneto-resistances under 8 T magnetic field at 4 K. Magneto-impedance measurement of the Pr0.7Sr0.3MnO3 nano particles have been obtained at 0.8 T in the temperature range 80-300 K. The magneto transport properties has been explored with spin polarized tunneling and spin dependent scattering of single ferromagnetic domain with nanometric grain size modulation. We have analyzed temperature dependent resistivity data using small polaron hopping and variable range hopping models. Below < 40 K a resistivity upturn behavior exhibiting a distinct resistivity minimum has been observed for each sample, which is best explained by electron-electron interaction and weak localization mechanism
