This paper admits a low-noise amplifier (LNA) designed by taking bio-medical applications into considerations. The amplifier is designed based on two gain stages, supply insensitive gain stage and inverter gain stage. Input-referred noise of the proposed amplifier is 18.02 mVrms and it consumes a power of 0.012 mW. The amplifier produces a gain of 86.5 dB. Bandwidth of the proposed amplifier is 227 Hz with cut-off frequencies as 227 Hz (higher) and 1 MHz (lower). The entire system is built in 45 nm technology with supply voltage of 0.6 V.