Abstract
To determine boron quantity in soil, water and biological samples, several protocols are available. Colorimetric assays are the simplest and cheapest methods which can be used to determine boron concentration. However, published protocols do not give straightforward guidance for beginners to adopt these protocols for routine use in the laboratory. Based on a previously published available procedure, we present a detailed and modified version of a curcumin based colorimetric protocol to determine boron concentration extracted from any sample. Our modified protocol is able to determine up to 0.2 nmole of Boron in a sample volume of 300 µl.
Keywords: Boron, Curcumin method, Protoplasts, Arabidopsis, Yeast
Background
Boron (B) can be quantified using spectrometric and colorimetric methods. Inductively coupled plasma mass spectrometry (ICP-MS) is the most sensitive method currently available having a detection limit of 0.01 mg/L (Kmiecik et al., 2016) but requires a sample volume of 5 ml. However, this technique requires sophisticated and expensive equipment which is not affordable for smaller laboratories. Alternatively, colorimetric based assays using curcumin or Azomethine-H dyes can be used for the routine analysis of boron in all laboratories with access to a spectrophotometer that can measure absorbance at 550 nm. Bingham (1982) reported that the curcumin assay is more efficient than the Azomethine-H based assay. Therefore, we present a modified version of simple and rapid curcumin assay to quantify B based on a protocol originally published by Wimmer and Goldbach (1999). We have used this protocol to determine the intracellular boron in yeast cells and Arabidopsis protoplasts. Additionally, this protocol can be used to study the uptake, root to shoot translocation-mechanisms of Boron in plants.
Materials and Reagents
Note: As boron leaches from lab glassware, all chemicals should be prepared in plastic bottles.
Equipment
Procedure
Recipes
Note: Every time make fresh solutions in a falcon tube.
Acknowledgments
This protocol is adapted from the original paper by Wimmer and Goldbach (1999). This work is supported by Biotechnology and Biological Sciences Research Council (BBSRC) grant (BB/N017765/1), United Kingdom. Authors declare no conflict of interest.
References
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