A simple and rapid Chlorella sp. surface expressed alkaline phosphatase (AP-algae) biosensor modified with flower shaped ZnO nanoparticles for the determination of chlorpyrifos in an aqueous medium was developed. The detection principle was based on the inhibition of AP-algae in presence of chlorpyrifos. Enzyme would dephosphorylate the phosphate monoester of substrate 2-phospho-l-ascorbic acid to release l-ascorbic acid, which was monitored using voltammetric and ISFET techniques. The presence of pesticide would inhibit AP-algae enzyme activity and hence the current magnitude decreases. The decrease in current is quantitative in nature and used for determination of concentration of the pesticide. Flower shape ZnO nanoparticles not only provide surface for adsorption of AP-algae for better immobilization but also increases electron-transfer kinetics and sensitivity of the biosensor. The voltammetric and ISFET methods could measure chlorpyrifos in the linear concentration range from 10⁻⁹ M to 10⁻¹ M and 10⁻¹⁰ M to 10⁻³ M, respectively, with nil interference from triazophos, malathion, acephate and some metal ions. Application aspects of the proposed biosensor were demonstrated using extracted soil samples and showed excellent reproducibility and reliability.

一个简单而快速的小球藻菌。开发了用花形ZnO纳米粒子修饰的表面表达碱性磷酸酶（AP-藻类）生物传感器，用于测定水性介质中的毒死rif。检测原理是基于在毒死presence存在下对AP-藻类的抑制作用。酶会使底物2-磷酸-1-抗坏血酸的磷酸单酯脱磷酸以释放l-抗坏血酸，使用伏安法和ISFET技术进行监测。农药的存在会抑制AP-藻类酶的活性，因此电流强度会降低。电流的减少本质上是定量的，用于确定农药的浓度。花形ZnO纳米颗粒不仅为AP藻类的吸附提供了更好的固定表面，而且还提高了电子转移动力学和生物传感器的灵敏度。伏安法和ISFET方法可在10 ^-9  M至10 ^-1  M和10 ^-10  M至10 ^-3的线性浓度范围内测量毒死rif M分别不受三唑磷，马拉硫磷，乙酰甲胺磷和一些金属离子的干扰。拟议的生物传感器的应用方面使用提取的土壤样品进行了演示，并显示了出色的可重复性和可靠性。