pH is a measurable parameter with implications in biology, chemistry, agriculture, and food science. In fact, pH initiates the color change in hydrangeas, where lower pH (around 5.2) allows aluminum intake, making the flowers appear blue. An increase in pH (around 6.0) prevents aluminum intake, thus turning the flowers pink.pH is measured on a scale from 0-14, where solutions with a pH < 7 is considered acidic, pH = 7 is neutral, and pH > 7 is basic. Specifically, pH is the relationship between hydrogen ions (H+) and hydroxide ions (OH-). Acidic solutions have more H+ than OH-, while neutral solutions have equal concentrations of H+ and OH- , and basic solutions have less H+ than OH-.
Given the importance of pH in the laboratory, it is important to choose a pH meter that is reliable and accurate. There are multiple aspects to consider with all the different types of pH meters available when choosing the best benchtop pH meter for your laboratory’s applications.
How Exactly Do pH Meters Work?
A digital pH meter for laboratory use is an electronic device consisting of a probe and visual display. The probe contains two electrodes: the reference electrode and sensor electrode that work in conjunction like a battery.
When the probe is placed in a solution, H+ ions displace metal ions on the probe, generating an electric flow. The pH meter detects this flow and converts it into a corresponding pH value by comparing the generated voltage from the reference electrode.
Due to the sensitivity of these instruments, it is critical to properly clean them every time they are removed from a solution, store them in proper buffer solutions, and calibrate them routinely.
Types of Digital pH Meters
There are multiple ways to measure pH, with digital pH meters being the most common in modern-day labs for data collection and solution-making.
There are three different types of digital pH meters:
- including pen pH meters
- handheld pH meters
- benchtop pH meters.
Pen pH meters are the smallest and most portable option, but can range in accuracy, where it is not always possible to replace electrodes when needed. Thus, pen pH meters have limited lifespans. Handheld pH meters are slightly more accurate but are better suited for field experiments where larger pH meters are impractical. The best lab pH meter is a benchtop pH meter, which is a highly accurate instrument that can be easily serviced by suppliers to increase lifespan.
While there are many different types of benchtop pH meters, automated pH meters, in particular, outweigh manual pH meters for multiple reasons. These include reducing human error, increasing consistency, minimizing hands-on time, improving safety, and being overall simpler to manage. An auto pH meter can analyze samples much faster than a human technician, where some models, such as the Rapid_pH, can quickly read the pH across 96- well microplates.
Features to Consider for the Best Benchtop pH Meter
When browsing laboratory pH meters, there are multiple aspects to consider. These include:
- Electrode Type
- Special Features
Ensuring a pH meter is accurate and contains electrodes compatible with your samples is critical for producing reliable and consistent results. Furthermore, some pH meters offer wider calibration ranges, which further improves accuracy.
The best benchtop pH meters typically store calibration settings and data results, where some can connect to hardware also to achieve this memory, thus supporting good laboratory practices (GLP).
Many labs can benefit from general pH meters. Some labs would greatly value pH meters accommodating specialized features, such as having a pH meter for viscous liquids or temperature sensitive samples.
What Is the Best Benchtop pH Meter for Your Lab?
Ensuring you have the best benchtop pH meter for your applications is critical for increasing laboratory efficiency and improving results.
Hudson Robotics offers multiple benchtop pH meters and add- ons for practical and specialized uses to help simplify your workload. To find out which is the best benchtop pH meter for your lab, speak to a representative today!