a b s t r a c tAs the industry surrounding microalgae continues to develop, there is a growing need for reliable, ready-to-use technologies for measuring the growth and composition of algal cultures. These can be new technologies or adapted existing technologies presently used for similar applications in other systems. Here we demonstrate the use of an LED fluorometer for the rapid estimation of dry weight, protein, and lipid content from two strains of microalgae. The instrument was successfully used to determine the dry weight of Chlamydomonas reinhardtii (CC-3491) and Scenedesmus dimorphus (UTEX 1237) cultures, at densities up to 1.58 g/L. Soluble protein was also measured using the instrument, and was highly comparable (average within 3%) to results obtained using both the Bradford and Lowry methods. Lastly, neutral lipid accumulation induced by nitrogen starvation was estimated via BODIPY 495/505 fluorescence. The basic methods developed here can easily be applied to any strain of microalgae or cyanobacteria, and demonstrate reliable, cost-effective, single-instrument methods for the determination of several key parameters in the cultivation of photosynthetic microorganisms.

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Quantification of DNA or RNA is often confounded by source contamination or inefficient purification. In addition, limited or sensitive samples may often force scientists to forgo quantification in order to avoid the potential of contamination. Here we describe the development and validation of three fluorescent reagents selective for the detection of DNA and RNA that are resistant to common sample contaminants such as salt, nucleotides, and protein. Moreover, the dsDNA reagents are resistant to contamination from different nucleic acid contaminants (such as nucleotides or RNA) while retaining their sub‐nanogram sensitivity. Likewise the RNA reagent is resistant to contamination from ssDNA, oligos and dsDNA while still able to detect low nanogram quantities of RNA. Compatible with either high‐throughput microplate based fluorometers, or low‐throughput single cell fluorometers, the assays were developed specifically for pairing with the dedicated quantification fluorometer, the Qubit™ fluorometer. The Qubit fluorometer is programmed with a unique curve fitting algorithm that reduces the standards from the eight normally used in plate readers down to two while retaining the same precision and accuracy.