Detection limit

About: Detection limit is a research topic. Over the lifetime, 34379 publications have been published within this topic receiving 644817 citations. The topic is also known as: limit of detection & lower detection limit.

Lowering the Detection Limit of Ion-Selective Plastic Membrane Electrodes with Conducting Polymer Solid Contact and Conducting Polymer Potentiometric Sensors

Abstract: The detection limit of conducting polymer (CP) poly(pyrrole)-based potentiometric chloride-sensitive electrodes was lowered over 3 orders of magnitude, applying anodic current of density in the range microamperes per centimeter squared. This effect was attributed to compensation of doping chloride ion leakage from the membrane into adjacent solution layer, caused by self-discharge of CP. This method was successfully applied to lower the detection limit of all-solid-state chloride-selective potentiometric sensors containing plastic, poly(vinyl chloride) chloride ion-selective membrane, and conducting poly(pyrrole) film applied as ion-to-electron transducer. The control of the leakage of chloride ions from the CP transducer phase to the plastic membrane resulted in linear response of ion-selective electrode shifted down to lower activities. A 2 orders of magnitude lowered detection limit, equal to 4 × 10-7 M, was achieved for current densities corresponding to extended linear range of CP film electrode, i.e...

Independent optimization of capillary electrophoresis separation and native fluorescence detection conditions for indolamine and catecholamine measurements.

Abstract: Separation conditions in capillary electrophoresis with native fluorescence detection often represent a compromise in terms of the separation and detection figures of merit. As both the separation and fluorescence properties greatly depend on pH, the ability to independently optimize pH in the separation capillary and the detection region can improve many complex separations. When using a sheath flow cell, the pH at the detection zone can be adjusted independently of the electrophoresis buffer pH. Using capillary electrophoresis with 257-nm excitation and native fluorescence detection, more than an order of magnitude improvement in the limits of detection for dopamine (from 1400 to 120 nM) and epinephrine (from 850 to 60 nM) is achieved by maintaining the basic separation conditions and an acidified sheath buffer. The detection of dopamine in an individual Aplysia californica cerebral ganglion neuron is demonstrated.