
The importance of expired reagent safety and handling cannot be understated. When reagents pass their expiration dates, degradation and contamination may occur, altering critical experiment data. In blood laboratories, using a less potent or flawed reagent produces inconsistent outcomes. This can skew blood work-up findings and as a result, lives may be put in harm’s way.
The gravity of the situation would seem to necessitate the mandated disposal of reagents when they reach their manufacturer’s shelf-life dates. However, following stringent best practices for handling expired lab reagents and retesting the products may allow for extended, safe, credible use.
In many cases, these products could remain viable for upwards of 20 percent longer than standard expiration dates. Still, this raises the question in many people’s minds: Can expired reagents be used safely?
What are Reagents?
Widely used in testing facilities, reagents are substances and compounds that elicit chemical reactions. The term “reagent” is generally used in a broad sense, encompassing both organic and inorganic substances.
The former helps initiate natural reactions, while the latter activates controlled, artificial responses. It’s also essential to keep in mind that not all reagents bring about proactive reactions. They also serve as limiting agents, preventing chemical responses from continuing.
Common reagent usage includes the following.
- Detection: Reagents help determine whether a substance is present or absent from another substance. During testing, color changes or reactions take place that provide a verifiable result.
- Synthesizing: Adding reagents to a substance can trigger a chemical reaction, resulting in the formation of a new compound. Reagent synthesization has proven successful in organic and inorganic chemistry.
- Testing: Routinely employed in blood testing laboratories, reagents enable scientists to determine glucose levels and detect the presence of antibodies.
- Quality Control: Reagents serve as a critical resource for various industries that require ongoing quality control testing. The results provide a fact-based resource to demonstrate and maintain industry standards.
- Environmental Assessments: Environmental scientists and researchers rely on these products to perform ecosystem testing.
Perhaps the best way to categorize reagents as an industry tool is to say they help manage chemical reactions. The information scientists and researchers gather from reagent-based testing allows them to make informed decisions.
Reagents vs Reactants
Although the terms are sometimes used interchangeably, reagents and reactants are different. When performing a chemical test, a reagent binds a substance and compound together. The binding process typically results in a chemical reaction, whether organic or inorganic.
By contrast, a reactant refers to one of the initial substances used in a procedure. Essentially, the difference between reagents and reactants is that reagents serve as catalysts, while reactants are foundational substances that may change or be consumed during the experiment.
Industries That Rely on Reagents
Widely used for quality control, analysis, research, and commercial processes, reagents enjoy broad use in a variety of industries. As one might anticipate, pharmaceutical companies rely heavily on reagents.
They are used to test purity, identify agents, and evaluate the raw materials used in life-saving medications. Without reagents, medications would not possess the efficacy needed to keep illnesses in check. And like the following industries, they support safe outcomes.
- Biotechnology: Fields such as molecular biology, biochemistry, and drug research and development put reagents to work as catalysts and indicators.
- Food Processing: The food processing industry employs reagents such as citric acid and sodium bicarbonate to ensure product safety. Manufacturing plants also package products in plastics made safe with the use of reagents.
- Healthcare: Laboratories work with reagents to test patients’ blood and urine to make accurate diagnostic assessments. Successful surgeries and other procedures rely on scientists using reagents to ensure the blood used in transfusions syncs with a patient’s unique biology.
It may come as something of a surprise, but the dyes and pigments used in textile and apparel manufacturing utilize reagents at varying points in the process. Sectors such as construction and automotive also heavily rely on them to help produce products with consistent quality.
Expiration Date Terminology
Laboratories deal with a wide range of moving parts that can lead to reagents exceeding their expiration dates. Much like consumers consider the “best used by” date on a canned good, supervisors and senior scientists weigh several factors before discarding reagents.
In many cases, they can still be used in routine testing. Some serve as backup materials, while others play a limited role. By understanding the specific terminology used to distinguish them beyond their expiration dates, inventories can be managed safely and effectively.
- Shelf-Life Dated Products: This class of products calls for manufacturer-specific storage conditions. When organizations adhere to safety standards, reagents maintain their properties and fulfill their intended life expectancy.
- Retesting Dated Products: Retesting reagents when they reach their expiration date enables users to determine their safe use and effectiveness. Based on quality, leadership teams and others can make an informed decision about whether to utilize or discard the material.
Certain products do not come with an expiration or retest date. Although they are considered indefinitely stable, quality assurance may prompt users to perform periodic testing.
Can Expired Reagents Be Used?
The majority of reagent manufacturers recommend that users properly dispose of products on or before their expiration dates. Unfortunately, laboratory administrators sometimes feel enormous financial pressure when performing vital testing on limited budgets.
Throwing away a reagent based solely on the maker’s end-use date does not always serve a scientist’s or facility’s best interest. That’s why testing and environmental factors are considered before discarding potentially viable products.
Storage Condition Factors
Proper storage conditions play an impactful role in the longevity of reagents. Manufacturers provide recommendations to maximize their product’s integrity and usefulness. When reagents are stored in places where the temperature exceeds guidelines, biological reagents tend to degrade more quickly. Products that must be frozen until use typically require minimal thaw times.
Exposure to light can also reduce the potency of reagents. These sensitive chemicals must be stored in unlit spaces to avoid diminished effectiveness. It’s also important to keep in mind that humidity normally leads to early degradation. Reagents housed in dark, cool, dry locations are more likely to exceed their expiration dates.
Contamination Risk Factors
Contamination jeopardizes the reliability of reagents before and after they reach shelf-life dates. This holds particularly true for products that are more susceptible to being negatively affected by biological or chemical agents. For example, chemical contamination results in dilution, making the reagent inherently less effective.
The growth of bacteria and fungi generally renders products unsuitable for use in cultures. That’s largely why sterility protocols such as sealed containers, sanitary or sterile disposable protective clothing, and bio-safe storage spaces remain crucial.
Best Practices for Handling Expired Lab Reagents
The improper handling of expired reagents poses a clear and present danger on multiple fronts. When technicians fail to wear disposable protective clothing such as chemical-resistant gloves and lab coats, skin contact may result in severe chemical burns.
The failure to wear breathable masks puts users at risk of inhalation, leading to lung and organ damage. Similarly, eyewear remains an industry-standard personal protective equipment (PPE) requirement to minimize the risk of impaired vision.
Perhaps the greatest hazard people face when retesting for viability stems from the fact that contaminated biological reagents put professionals at risk of infection. While researchers, technicians, and scientists are tasked with proper storage, equipment sanitization, and inventory management, it’s essential for facilities to maintain a comprehensive supply of PPE and disposable protective clothing at all times.