Green Analytical Chemistry and Flow Injection Methodologies

LUIS DANTE MARTINEZ, SOLEDAD CERUTTI, RAÚL ANDRÉS GIL

Handbook of Green Analytical Chemistry

John Wiley & Sons

Año: 2012; p. 320 - 338

The term ‘Green Chemistry’ was first used in 1991 [1, 2]. Green chemistry gives us new tools that permit chemists to perform chemistry in a more environmentally benign manner. Therefore, philosophy and ideas on green chemistry are those previously developed in analytical laboratories (GAC). This concept refers to the utilization of chemistry techniques and methodologies that reduce or eliminate the use or generation of feedstocks, products, by-products, solvents, reagents, and so on that are hazardous to human health or the environment as a whole. Taking into account current public concern on environmental matters, environmental analytical studies and the consequent use of toxic reagents and solvents have increased to a point at whichthey became unsustainable to continue without an environmentally friendly perspective [3]. The adverse environmental impact of analytical methodologies has been reduced in three different ways: (1) reduction of the amount of solvents required in sample pretreatment; (2) reduction in the amount and the toxicity of solvents and reagents employed in the measurement step, especially by automation and miniaturization; and (3) development of alternative direct analytical methodologies not requiring solvents or reagents. Milestones of both concepts and methodologies leading to the present state of GAC occurred in the twentieth century; J. Namies´nik et al. resumed them all in a recent article [1]. Among these concepts and methods, the development of flow injection analysis (FIA), sequential injection analysis (SIA), and miniaturization of analytical systems are highlighted.The analytical process is comprised of several steps such as field sampling, field sample handling,laboratory sample preparation, separation and quantitation, and statistical evaluation. Though each step can affect the environment, they make different contributions towards pollution and have different potentials for being made greener [4]. For these reasons, analytical chemists tried to change the application of existing analytical methodologies and looked for new ones that could use smaller amounts of harmful solvents and reagents, and less energy. The process accelerated when ecological consciousness increased considerably, resulting in ‘greener’ analytical procedures, miniaturized analytical instruments and the lab-on-valve concept.This chapter attempts to examine the state-of-the-art of Green Analytical Chemistry within the most popular automated and flow injection techniques of analysis.