Many photosynthetic studies with macroalgae are based on oxygen evolution. This approach is preferred over 14C tracer techniques since oxygen electrodes are generally inexpensive and radioactive wastes are not produced. Nevertheless, oxygen techniques do not directly measure carbon assimilation; thus, primary production estimates rely on the conversion of oxygen units to carbon units via a phot...

Most commercially available optical oxygen sensors target the measuring range of 300 to 2 μmol L-1. However these are not suitable for investigating the nanomolar range which is relevant for many important environmental situations. We therefore developed a miniaturized phase fluorimeter based measurement system called the LUMOS (Luminescence Measuring Oxygen Sensor). It consists of a readout de...

There have been a variety of nanoparticles created for in vivo uses ranging from gene and drug delivery to tumor imaging and physiological monitoring. The use of nanoparticles to measure physiological conditions while being fluorescently addressed through the skin provides an ideal method toward minimally invasive health monitoring. Here we create unique particles that have all the necessary ph...

Heavy metal exposure from anthropogenic pollutants negatively affects many marine organisms, including foraminiferan protists. As such, foraminifera are often used as bioindicators of stressed environmental conditions. Primary research has commonly focused on how heavy metals affect foraminiferal assemblages, ultrastructure, and shell morphology; however, little if any data have been reported t...

The present study proposes a simple and inexpensive photometric method for the selective determination of Ag(I). This employed home-made double beam photometer silver ions based on an optode sensor prepared by immobilization 5-(P-Dimethylaminobenzylidene)-rhodanine (PDR) triacetyl cellulose (TAC) membrane. Two green LEDs as sources light light-dependent resistors (LDRs) detectors were used in p...

In this work we have examined the use of plasticiser-free polymeric films incorporating a proton selective chromoionophore for optical pH sensor. Four types of methacrylic-acrylic copolymers containing different compositions of n-butyl acrylate (nBA) and methyl methacrylate (MMA) were synthesised for use as optical sensor films. The copolymers were mixed with appropriate amounts of chromoionoph...

1 UMR 7093, Laboratoire d’Océanographie de Villefranche (LOV), Centre national de la recherche scientifique, Sorbonne Universités, UPMC Université Paris 06, Villefranche-sur-Mer, France, 2 GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, Kiel, Germany, 3 Christian-Albrechts-Universität zu Kiel, Kiel, Germany, 4 CSIRO Oceans and Atmosphere, Hobart, Australia, 5 Monterey Bay Aquarium Research In...

Algae-derived dissolved organic matter has been hypothesized to induce mortality of reef building corals. One proposed killing mechanism is a zone of hypoxia created by rapidly growing microbes. To investigate this hypothesis, biological oxygen demand (BOD) optodes were used to quantify the change in oxygen concentrations of microbial communities following exposure to exudates generated by turf...