Following the trend towards smaller channel inner diameter for better separation performance and shorter channel length for shorter transport time, a modular construction of a miniaturized 'total chemical analysis system' is proposed. The theoretical performances of such systems based on flow injection analysis, chromatography and electrophoresis, are compared with those of existing chemical sensors and analysis systems.

Miniaturized total chemical analysis systems: A novel concept for chemical sensing

Carrier-Based Ion-Selective Electrodes and Bulk Optodes. 1. General Characteristics.

Polymers in sensor applications

To a certain extent, all cellular, physiological, and pathological phenomena that occur in cells are accompanied by ionic changes. The development of techniques allowing the measurement of such ion activities has contributed substantially to our understanding of normal and abnormal cellular function. Digital video microscopy, confocal laser scanning microscopy, and more recently multiphoton microscopy have allowed the precise spatial analysis of intracellular ion activity at the subcellular level in addition to measurement of its concentration. It is well known that Ca2+ regulates numerous physiological cellular phenomena as a second messenger as well as triggering pathological events such as cell injury and death. A number of methods have been developed to measure intracellular Ca2+. In this review, we summarize the advantages and pitfalls of a variety of Ca2+ indicators used in both optical and nonoptical techniques employed for measuring intracellular Ca2+ concentration.

https://www.physiology.org/doi/pdf/10.1152/physrev.1999.79.4.1089

Measurement of Intracellular Calcium

The endoplasmic reticulum (ER) is the largest single intracellular organelle, which is present in all types of nerve cells. The ER is an interconnected, internally continuous system of tubules and cisterns, which extends from the nuclear envelope to axons and presynaptic terminals, as well as to dendrites and dendritic spines. Ca2+ release channels and Ca2+ pumps residing in the ER membrane provide for its excitability. Regulated ER Ca2+ release controls many neuronal functions, from plasmalemmal excitability to synaptic plasticity. Enzymatic cascades dependent on the Ca2+ concentration in the ER lumen integrate rapid Ca2+ signaling with long-lasting adaptive responses through modifications in protein synthesis and processing. Disruptions of ER Ca2+ homeostasis are critically involved in various forms of neuropathology.

https://www.physiology.org/doi/pdf/10.1152/physrev.00004.2004

Physiology and Pathophysiology of the Calcium Store in the Endoplasmic Reticulum of Neurons

We review ion-selective solvent polymeric membrane electrodes for clinical use. The particular requirements that the clinical application set on the membrane are discussed in terms of selectivity, stability, lifetime, and response time. The performance of currently available electrodes is reviewed, with consideration of actual problems that arise in clinical practice.

Ion-selective membrane electrodes for clinical use.

Lifetime of neutral carrier based ion-selective liquid-membrane electrodes

Formation du complexe 1:3 Ca ++ /N,N,N',N'-tetracyclohexyl-3-oxapentanediamide La limite de detection de la fonction reponse de l'electrode est environ 100 pM Ca 2+

Neutral carrier based calcium(2+)-selective electrode with detection limit in the sub-nanomolar range

Donnees sur une nouvelle serie d'ionophores pour ions hydrogene, utilisables avec des electrodes de pHmetrie, a membrane polymere

Urs Oesch

Papers

Ion-selective membrane electrodes for clinical use.

Lifetime of neutral carrier based ion-selective liquid-membrane electrodes

Neutral carrier based calcium(2+)-selective electrode with detection limit in the sub-nanomolar range

Design of neutral hydrogen ion carriers for solvent polymeric membrane electrodes of selected pH range

Field effect transistors sensitive to sodium and ammonium ions