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Green and Sustainable Approaches in Pharmaceutical Sciences

Shiv Bahadur1, Radhika1, Durgesh Nandini Chauhan2, Nagendra Singh Chauhan3 and Kamal Shah1

1 Institute of Pharmaceutical Research, GLA University, Mathura, UP, India
2 Columbia Institute of Pharmacy, Raipur, CG, India
3 Drugs Testing Laboratory Avam Anusandhana Kendra, Raipur, CG, India

CONTENTS

• 1.1 Introduction,
• 1.2 Green Solvents,
• 1.3 Nanoparticle Formulations,
• 1.4 Antimicrobial Bandages,
• 1.5 Green Drug Synthesis,
• 1.6 Green Nanotechnology,
• 1.7 Benefits of Green Technologies,
• 1.8 White Biotechnology and Green Chemistry,
• 1.9 Conclusion,

1.1 Introduction

The pharmaceutical industry contributes around $1.27 trillion to the global economy, making it one of the world's largest contributors. At the same time, these businesses emit around 1.9 million metric tonnes of carbon dioxide each year. Environmental protection is a constant goal for the regulatory agencies that oversee various sectors across the world, including pharmaceuticals. Sadly, however, firms' in-house systems are not as good as they should be. Several creative concepts for environmental protection have been developed, but most of them have failed because of a lack of engagement with the world's largest pharmaceutical companies [1, 2].

New environmentally friendly, safe, and effective pharmaceuticals are the goal of all pharmaceutical firms. In order to achieve this goal, the industry must switch from synthetic to eco-friendly materials. Companies in a number of sectors have begun to use green chemistry techniques in an attempt to replace their old-fashioned ways of manufacturing [3]. Ecologically friendly green chemistry's primary goals are to maximise energy efficiency, reduce waste, and employ renewable energy sources for power generation. Green chemistry may help limit the amount of waste products that are generated throughout the process of synthesis, such as solvents, contaminants, and exhausted reagents. Pharmaceutical corporations have broad influence in this area and could make significant contributions. As a result, it is important to investigate various green chemical methods and discover the gaps in their use [4].

In the pharmaceutical industry, green chemistry techniques are in great demand and have been developed in recent decades within a new approach that addresses issues such as pollution, limited environmental resources, and renewable sources of materials. The pharmaceutical industry is under increasing pressure to improve both its production efficiency and the implications of its products as environmental degradation and better testing procedures are becoming more widely known. Employing green chemistry practices does not necessarily equate to cost-effectiveness, however. Incorporating the concepts of green chemistry may be seen as an extra challenge, and the commercialisation of green technology is being thwarted by a lack of capital investment [5].

In order to implement green processes, various modifications must be made to the lengthy global supply chain. In addition to intellectual property and fail-fast requirements, challenges such as safety and the occupational health management of those participating in the process must be considered. Although green chemistry lessens the sector's dependency on fossil fuels, there is still a dearth of real government subsidies for alternative energy resources and setting up pharmaceutical enterprises. New restrictions on environmental contamination of water sources, both from industrial waste and from the residues of medications and medicines discharged in water bodies as municipal liquid waste, are another issue facing pharmaceutical companies. Even at very low levels, research has shown that drugs and their metabolites damage lakes, rivers, and coastal areas. Fish and other benthic creatures are particularly vulnerable to the effects of large quantities of drugs. Pharmaceutical companies are generally aware of these issues and take them seriously, but the rules in place do not always benefit the industry [3].

The difficulty of obtaining readily available green feedstock materials has been cited as a fundamental obstacle to the widespread use of green synthesis. If such materials cannot be sourced, it is probably because they do not exist at the right degree of detail or simplicity. They may not be in a format that is easy to use or tailored to a particular industry.

A broad range of solutions are needed to deal with the issues that arise in the use of green and sustainable chemistry. As an example, green chemistry training that emphasises the fundamentals of process excellence in design, biocatalysis, and the selection of solvents and reagents is highly recommended. While reducing carbon emissions should be a priority, it is equally important to employ renewable energy resources wisely, manage water use efficiently, and reduce trash output [6]. However, although the scientific community has largely embraced the idea of green chemistry, the technological progress of green chemistry has yet to be achieved via education and awareness. Traditional chemical industries must undergo a major shift to become more sustainable. There must be collaboration between education, politics, and economics, as well as a multidisciplinary commitment to equality and metrics [2, 7].

Research institutions and universities have been working for years towards greener chemistry, which is now being used in numerous industries. There is still a lot of work to be done, not just in terms of research but also in terms of how we think about chemistry and synthesis and what it can do for our well-being and advancement in technology and society. There will come a point in the future when pharmaceutical chemists will no longer need to be taught about green chemistry since it will be included in the natural sequence of operations. Green chemistry is now gaining significance on a world scale. Not only does it help the environment, it also results in high-quality goods with few hazardous residues. If the current situation of the pharmaceutical sector and the difficulties it faces, such as environmental issues, high costs, and other challenges, are examined, it is clear that green chemistry offers a novel approach for improving living standards while reducing environmental problems [6]. Reductions in the use of harmful chemicals and solvents and the substitution of those materials with more environmentally friendly, renewable alternatives may lower emissions and save water. The pharmaceutical business and medicine production might be transformed in the future by green chemistry. It benefits the ecology and the economy at the same time. As a consequence, the conventional pharmaceutical industry will be transformed into one that is more environmentally friendly and sustainable [2, 7].

Even so, green chemistry ideas and practices have been effectively adopted by pharmaceutical companies in a number of countries [8]. Some of the successful end goods and technologies that have gained prominence in recent years are described in the rest of this chapter.

1.2 Green Solvents

Green solvents can be employed as an alternative to traditional solvents. In their green chemistry principles, Anastas and colleagues advocated the use of 'safer solvents and auxiliaries'. Combustible organic solvents are used in various synthesis processes; nevertheless, these conventional solvents are damaging to the environment and poisonous. Thus, green solvents are currently replacing conventional solvents in numerous industries [9, 10]. There is a wide variety of solvents, and the choice of a suitable solvent for a particular reaction can be crucial to the success of a reaction technique. When choosing a solvent for a reaction, the qualities that should be considered are chemical compatibility with reagents and products; solubility of reagents; and procedure temperature [2, 7].

Sertraline hydrochloride, a greener solvent, was produced using chemical reagents such as toluene, hexane, tetrahydrofuran (THF), and metal salts such as titanium tetrachloride (TiCl4). When these solvents were substituted with water and the palladium on carbon (Pd/C) catalyst was removed, it provided a more selective and environmentally friendly method.

1.2.1 Water as a Solvent

The ever-increasing demand for a more sustainable approach in synthesis operations has led to a growing interest in using water as a solvent. The use of water as a solvent in chemical synthesis is one of the best ways to minimise the release of dangerous compounds into the environment, according to green chemistry. When using water as a solvent, reactions are frequently conducted under mild experimental conditions and consequently the catalysts are frequently reused, which reduces the overall price of the product [6].

1.2.2 Ionic Liquids

In the context of green solvents we can discuss ionic liquids, which, at least for a time, are considered not only as designer solvents but also as green solvents, primarily because they require negligible vapour pressure and do not contribute to the problem of volatile organic compounds [11]. Green technology involves the synthesis of biodiesel and bioethanol from transesterification of vegetable oil. During biodiesel production, a vast...