BATCH INJECTION ANALYSIS FOR HIGH-SPEED BIOSENSING

Abstract

The principles of a new, non-flow, injection technique, termed batch injection analysis (BIA), for high speed biosensing are described. BIA is based on the reproducible injection of small samples toward a nearby detector, which is immersedin a large-volume stirred bulk solution. Passage of the sample zone over the detector surface results in sharp peak readouts, similar to those of flow injection analysis (FIA). Sample throughputs and size, the sensitivity, detection limits and reproducibility, are also similar to those of FIA. In addition, the need for pumps and connecting tubingsis eliminated. Becauseof the limited solution handling capability, BIA relies on the use of specific or reactive sensing surfaces. In particular, the inherent specificity of biosensors makes them extremely attractive for the BIA operation. Such characteristics and advantagesareillustrated for the use of enzymes or tissues, coupled to amperometric, potentiometric or thermal BIA detectors. The high-speed and simple BlA/biosensing operation holds a great promisefor clinical screening and bioprocess monitoring.