Biochemical Engineering

Biotechnology

Biochemical engineering is a subfield of engineering focused on the creation of substances to be used in the production of food or industrial materials, using biological as well as manufactured chemical ingredients. Some biochemical engineers, for example, have discovered how to get bacteria to help break down oil spills in order to minimize the environmental impact of such disasters.

Much of a biochemical engineer's time is spent studying different substances and biological processes to better understand how they work. With this knowledge, these substances and processes can be repurposed or redirected to meet society's needs for advanced materials.

The main purpose of DNA and similar proteins in an organism is to produce different chemical substances to keep the organism functioning. Biochemical engineers can cause DNA strands to act like miniature factories, producing the chemicals needed for a particular application. If a certain type of enzyme is needed to treat a disease, for example, it may be possible to locate a DNA segment in an organism that either naturally creates this material or can be “reprogrammed” to create it. In order to do so, biochemical engineers must be able to study the structure and composition of biomolecules (biological molecules).

Scientists use various techniques to study and analyze substances of interest. First, a sample of the substance must be prepared. This usually begins with blotting, which isolates DNA and other proteins for further study. When studying DNA, the sample may then be amplified in a polymerase chain reaction (PCR) machine. Polymerase chain reaction is a technique for producing many copies of a DNA strand. This allows close analysis or multiple tests to be performed on even a very small sample.

Interferometry refers to several related techniques involving wave superposition. In most cases, identical electromagnetic waves are reflected from both the sample material and a reference, then superimposed. The reference may be another substance, or it may be a mirror that reflects the wave unaltered. The resulting interference pattern will reveal any structural differences between the two samples. Interferometry can be used to identify materials, study their molecular structures, or provide detailed tissue imaging.

Affinity chromatography is a method for separating specific substances from mixtures. “Affinity” refers to the fact that certain biomolecules have a strong tendency to bind to other specific types of molecules. For example, an antigen is a harmful biomolecule that elicits an immune response in an organism. The immune system responds by producing antibodies, which are proteins that are “designed” to bind to that specific antigen. Thus, if a researcher wanted to separate antibodies from a biochemical mixture, they would introduce antigens specific to those antibodies into the mixture. The antibody molecules would separate from the mixture and bind to the antigens instead. Affinity chromatography can be used to purify or concentrate a substance or to identify substances in a mixture.

The task of a biochemical engineer is to look at real-world problems and at the chemical and biological properties of organisms and materials as if they were pieces of a jigsaw puzzle, and find matches where two pieces fit together. They match up problems with solutions.

Biochemical engineers spend much of their time on design and analysis, but they are also involved in other tasks. Much of their time is spent working on product development. The overarching goal of the design work they do is to further the creation of products that will benefit society and generate profits for the company that markets them. Product development requires a biochemical engineer to develop a thorough understanding of the needs and goals of a project in order to research potential solutions that fit with those needs. In the case of products with medical applications, there are also elaborate safety precautions that must be taken, as well as lengthy approval processes requiring cooperation with regulatory agencies.

Documentation and scholarly publishing are also important duties for biochemical engineers. Each stage of their research must be recorded and analyzed. Biochemical engineers are encouraged to share their findings with the global research community whenever possible. While this sometimes raises concerns about the confidentiality of proprietary information, in the long run the sharing of research helps advance the field and encourage innovation. Many discoveries in the field of biochemical engineering are carefully guarded because of their profit potential, as patents on biochemically engineered substances can be worth large amounts of money. This is why the patent system tries to balance monetary rewards for inventors against society's need for access to information.

One of the greatest applications of biochemical engineering is in the field of drug manufacturing. Traditional pharmaceutical manufacturing processes involve multiple types of chemical reactions, each a laborious step in the process of creating a batch of medicinal compound. Biochemical engineers reinvent this process by putting nature to work for them. They identify biological processes that can be tweaked to produce the same drugs without having to mix chemicals.

One newer area of research in biochemical engineering is the artificial production of human organs through processes similar to 3-D printing. By studying the ways that different types of tissue cells reproduce, biochemical engineers have been able to grow rudimentary structures such as replacement ears. Scientists anticipate that they will eventually be able to produce fully functioning hearts, livers, and other organs, avoiding the need for organ donation.

—Scott Zimmer, JD