An impedimetric biosensor platform for bio-affinity assays was developed based on real-time, label-free electrochemical detection performed via direct interface to electronic digital data processing. The sensor array consists of 15 gold microelectrode pairs enclosed in three reaction chambers and bio-functionalized with specific DNA probes. The impedance change caused by specific target analyte binding to the functionalized electrode surface is recorded in real time. The detector is capable of continuous and simultaneous stimulation and recording of all array electrodes. A corresponding mathematical algorithm, and a software package for data analysis were developed and used to quantify both the rate of target to probe binding, and target to probe affinity. The biosensor was capable of distinguishing between closely-related bacterial strains. This fully-integrated sensor array platform can be used for detection of a wide range of analytes of practical significance, and has potential for further integration with amplification (i.e. PCR) and sample preparation modules.