Many lab processes involve regularly monitoring water quality or inspecting liquid compounds. Spectrophotometry is an integral part of this analysis, so choosing spectrophotometer equipment carefully is essential. One of the most popular of these tools is a UV-Vis spectrophotometer.

UV-Vis spectrophotometers are widespread today, but popularity alone is not enough justification for using one in your lab. Like any piece of equipment, it is ideal in some situations but not in every scenario, so reviewing your specific needs and comparing them to what these tools can offer is crucial.

What Is a UV-Vis Spectrophotometer?

UV-Vis spectrophotometers, sometimes more simply referred to as UV spectrophotometers, pass visible and ultraviolet light through a sample to measure how much it absorbs or transmits. They operate on the Beer-Lambert Law, which holds that a chemical solution’s composition is directly proportional to its light absorption, so weaker light on the other side of a solution suggests a stronger concentration.

In addition to measuring light passing through a solution, UV spectrophotometers measure how it reacts to electromagnetic waves across the ultraviolet and visible spectrum. As a result, they can reveal the chemical composition of a sample as well as its concentration.

The most basic UV spectrophotometers use a single light beam, but you can also find double-beam spectrophotometers, which offer more accuracy by monitoring a reference beam. Some options today also include various filters to eliminate unwanted wavelengths in the testing process.

Advantages of UV-Vis Spectrophotometry

If your lab is considering installing a UV-Vis spectrophotometer, it helps to start by outlining the potential benefits. One of the most significant advantages in the process is non-invasive and non-destructive. Consequently, you can use the solution in other tests or pass it along for production after testing it in the spectrophotometer.

UV spectrophotometry is also fast. The process only takes a few minutes, most of which is setting up the samples for testing. Similarly, many spectrophotometers are user-friendly, requiring little to no training to use them correctly.

Because equipment inspection and maintenance are vital parts of lab safety, that ease of use has safety benefits. It also reduces the chances of user error, making UV-Vis spectrophotometry highly accurate. Using both the visible and ultraviolet spectrums helps identify a wide range of contents in varying concentrations with little room for error in many cases.

Disadvantages of UV-Vis Spectrophotometry

Of course, like any equipment, UV-Vis spectrophotometers also carry some unique disadvantages. Your lab should weigh these potential downsides against the benefits to see if these tools suit your processes.

One of the largest drawbacks of UV spectrophotometry is it is not a reliable way to measure suspended solids. While these spectrophotometers are highly accurate with liquids and solutions, suspended particles can cause light scattering, which may result in measurement errors.

UV-Vis spectrophotometry also requires a pristine environment to work effectively. Any outside light, electric noise or other contaminants could affect the results, so labs must set them up carefully. Pre-analytical errors account for 70% of all lab diagnostic mistakes, so these stringent setup requirements may increase the chances of inaccurate results if technicians are not careful.

Similarly, labs must choose their solvents and calibrate their equipment carefully to achieve reliable results. Every solvent has a unique UV absorbance cutoff wavelength, so failure to understand and account for these will produce inaccurate results.

When to Use a UV-Vis Spectrophotometer

Given these advantages and disadvantages, labs should determine if they need a UV-Vis spectrophotometer based on the analyses they must perform, accounting for workforce considerations, too. Here are some ideal use cases for the technology to provide a baseline of optimal conditions for UV spectrophotometry.

DNA and RNA Analysis

DNA and RNA analysis are some of the most common applications of UV spectrophotometry. Both have specific, well-known absorbance wavelengths, so you can use a UV-Vis spectrophotometer to determine their concentration accurately.

This method can also reveal if samples are contaminated by analyzing genetic material, helping inform further tests. If the solution lets less light pass through than it should or reacts differently to the ultraviolet spectrum, there are likely contaminants like other proteins on the DNA sample. You can then choose another sample to test or identify when an earlier process might have affected it.

If current trends persist, the RNA analysis market could be worth $53.6 billion by 2033, thanks to breakthroughs like the COVID-19 vaccines. In light of this growth, UV-Vis spectrophotometry could become essential for biotechnology companies looking to capitalize on this trend.

Pharmaceutical Analysis

UV-Vis spectrophotometers can also reveal drug concentrations in a solution. Consequently, they are an ideal tool for the pharmaceutical industry. Using this equipment to monitor pharmaceuticals in development or production will help ensure they deliver safe and effective doses.

Similarly, UV spectrophotometry can determine drug, alcohol or other substance concentrations in blood samples. This chemical composition analysis helps forensic labs solve crimes, but you can also use it to monitor and quantify a treatment’s effects. After delivering a dosage to a patient in clinical trials, you can test their blood with UV spectrophotometry to see how much remains in the system after a given period.

Because many pharmaceutical products and substances like alcohol have known UV absorbance wavelengths, UV spectrophotometry is an ideal way to measure them. Its high accuracy is also crucial for these high-precision workflows.

Bacterial Culturing

Culturing bacteria is another ideal use case for UV spectrophotometry. Routine, precise measurements are essential for tracking bacterial growth and concentration, but some cells are sensitive to specific electromagnetic wavelengths. UV-Vis spectrophotometers let you adjust them to the right band to monitor bacteria cultures without damaging the cells.


Because UV spectrophotometry is non-destructive, it is an optimal tool for tracking growth while enabling ongoing experimentation. Its ease of use and high testing speed are also advantageous in this use case, as they make it easier to perform routine measurements throughout a project.

One of the most valuable applications of this monitoring is to gauge the efficacy of antibiotics. Measuring bacteria cultures before and after introducing antibiotics will reveal how much bacteria the solution kills over time. The non-destructive nature of UV spectrophotometry assures that any of these results will be from the antibiotics themselves, not other interference.

Color Analysis

UV-Vis spectrophotometry can also accurately measure colors, as a color’s intensity and hue are directly related to its wavelength. This color analysis is essential for labs making over-the-counter pharmaceuticals, where the products’ aesthetics may impact sales performance.

You can also use this type of color analysis to monitor chemical reactions that may subtly change a solution’s color. Using a UV spectrophotometer for this analysis is preferable to gauging color with the naked eye, as it offers hard data on the specific wavelengths passing through the sample.

Over-the-counter medicine sales have steadily increased, reaching $41.2 billion in 2022, which suggests this market will only get increasingly competitive. Subtle markers like product colors could help pharmaceutical companies stand out and remain competitive amid this growth.

Use the Right Technology for Your Analysis Needs

A UV-Vis spectrophotometer is an excellent tool for these use cases and similar applications, but others may need different equipment. To make the right choice, review these benefits and compare them to your lab’s needs.

Overall, if you need to analyze concentrations in a liquid accurately and quickly, and your samples do not include suspended solids, UV-Vis spectrophotometry may be the ideal approach for your lab. Understanding these technologies and their unique advantages and disadvantages will help you make the most informed decisions.