We design an ISFET array leveraging on the two successful fields of neuromorphic and chemical sensing to encode the signal in spikes and perform sensor processing between neighbouring pixels. The array is structured as clusters integrating 4 x 4 pixels with sensor compensation, taking advantage of spatial correlation of sensor non-idealities. The offset compensation is capable of calibrating in a range of 662 mV. The system shows a robust, scalable and power efficient architecture with a sensitivity ranging from 2.56 MHz/pH to 3.38 MHz/pH. The pixel occupies an area of 30 um x 24 um, and the cluster area is 205 \um x 205 um. The layout of each pixel is spread out with digital blocks embedded in-between, which improves signal coupling by enlarging the chemical sensing area of each pixel. The system readout implements address event representation (AER) for triggering the outputs.