Measuring Chlorophyll a with a Spectrofluorophotometer

User Benefits

- The seawater concentration of chlorophyll a or total chlorophyll a can be measured by fluorometry with sample pretreatment. - When measuring chlorophyll a, fluorescence measurements with a spectrofluorophotometer give higher signal intensities, better sensitivity, and can detect lower concentrations compared with absorbance measurements using a spectrophotometer.

Introduction

The oceans are inhabited by a variety of organisms, each of which is located on an ecological pyramid. Positioned at the very bottom of this ecological pyramid is a class of organisms called phytoplankton. Phytoplankton are mainly found close to the surface in coastal zones fed by rivers, and are less common in non-coastal tropical or subtropical zones. Phytoplankton are an important indicator organism as they provide us with information about the lowest strata of the marine ecosystem. The amount of phytoplankton in seawater can be determined by measuring the concentration of chlorophyll. The Guideline of Ocean Observations (The Oceanographic Society of Japan) describes several methods for measuring chlorophyll, which it classifies as an algal pigment. This article describes measuring the amount of chlorophyll in various water samples using the fluorometric method presented in these guidelines. This fluorometric method is also compared with an absorption spectrophotometry method for measuring chlorophyll that is also presented in the guidelines.

August 20, 2026 GMT