Daniel Harris of BYK Additives & Instruments discusses the current landscape of spectrophotometry, and considers how portable devices are widening access to this colourful field…
One measure of a good tool is how often it is implemented by professionals in a wide range of demographics and a perfect example of this is the spectrophotometer. This device measures light intensity, which can tell a surprising amount based on how you use the information. Common uses include colour measuring or matching, solution identification and quality control, but the device is only limited by the imagination of the user. Traditionally, spectrophotometers are found on lab desks with people first being introduced to them in undergraduate chemistry or biology courses. However, as technology has become more refined, portable spectrophotometers are becoming more common in industry and production where they assist with quality control.
[These devices] have their own light sources that vary based on use, which means the environmental light does not factor into the readings. For example, a company producing plastic door handles for a particular automobile manufacturer will be able to confirm that the colour exactly matches the interior of the rest of the car.
Spectrophotometers are invaluable tools for many researchers, especially those working within the fields of medicine, forensics, biology and chemistry. Medical professionals are able to use the devices to test blood samples for carbon monoxide poisoning, pigment concentration and percentages of foreign bodies. Indeed, blood is just one of many solutions commonly tested by clinicians using spectrophotometry. When a sample is unknown, forensic scientists can use spectrophotometers to identify the substance. The devices can be used to measure a solution’s absorption of different wavelengths, and these can be compared with other known solution wavelengths until a match is found. Spectrophotometry can also be used in conjunction with reverse engineering to identify specific components of – and the percentages that comprise – particular solutions. In a similar manner, biologists use spectrophotometers to conduct measurements within different areas of their discipline. The tool can be used to calculate the constituent percentages of DNA and RNA, and can also facilitate observations of growth or decay within a culture. Within the field of chemistry, spectrophotometers have proved particularly useful because chemical reactions often cause a solution to change its colour. Because the devices measure wavelengths, they are capable of detecting even the tiniest change in a substance’s colour.
As one might expect, historically, spectrophotometers have been most widely utilised within the scientific community. However, industry is catching up quickly. The tools are most often used for quality control when it comes to colour
. In today’s globalised society, a finished product can have parts made all over the globe and all of these parts can be made up of different materials under different lighting that can make colours look different.
Spectrophotometers have their own light sources that vary based on use, which means the environmental light does not factor into the readings. For example, a company producing plastic door handles for a particular automobile manufacturer will be able to confirm that the colour exactly matches the interior of the rest of the car.
Spectrophotometers vary based on the niche they’re being used in and there are many different types of models that can be customised accordingly. For example, NanoDrop spectrophotometers measure very small sample sizes which keeps forensic scientists from wasting too much of their sample, and there are models that offer temperature control for the sample so chemists can control their catalysts. Most of the spectrophotometers used in labs are desk mounted, but technological advances have led to portable spectrophotometers which are largely used in production. Based on what needs measuring, different models offer wide or specific ranges of wavelengths from the visible spectrum to ultraviolet and infrared.
Spectrophotometers are an example of a technology traditionally thought of as a lab tool that has become sufficiently accessible to expand into the private sector. Whilst the tools are still costly for small companies and laboratories, it is only a matter of time before they become as commonplace as the carpenter's measuring tape or the doctor’s stethoscope. In the meantime, let’s just hope that somebody thinks of a shorter name for the tools.