At present, just 40% of labs utilize automated titration. It is possible that it may be difficult to convince people within businesses that there are many benefits, even though automation has continuously been proven to be the superior method.
Image Credit: YSI
How Do Titrations Work?
Titrimetry is volumetric analysis, and more commonly known as titration and is a chemical analysis method. It was established in the 18th century at the start of industrialization, followed by the first usage of glass burettes in 1890. Over time, scientists have been able to develop several types of titrations that are used for thousands of applications.
Regardless of whether it is a manual or automated titration, the fundamentals for a titration remain the same.
- Titration consists of a collection of analytical methods that focus on determining the quantity of a reagent of a known concentration. This is needed to react completely with the analyte. The reagent may be a standard chemical solution or an electric current of identified magnitude.
- A standard solution, or a standard titrant, is a reagent of known concentration that is utilized to perform a titrimetric analysis.
- A titration is complete when a clearly recognizable endpoint or equivalence point is reached.
Within the industry, manual titrations have continued to be popular because of the apparent relative low cost and simplicity. To perform a manual titration, the equipment required is a Class A glass burette, standardized titrant, sample, color indicator, and a person to perform the task.
Nevertheless, it is only possible to yield accurate and reproducible results through this method when completed by a skilled technician. Gaining these skills requires advanced academic training and/or on the job training.
The main benefit of manual titrations, and the reason why 60% of labs rely on this method, is mainly due to low initial costs. If an application is basic and accuracy and reliability is not a noteworthy concern, manual titration is likely to be the best solution.
Phenolphthalein is a common indicator and it changes numerous shades of pink as there is an increase in pH. An individual might call the endpoint depending on how they perceive the “pink” color. This form of simple titration is often used in high school and college chemistry courses. It highlights that the operator is one of the main issues with manual titration.
To guarantee accurate and consistent results, manual titration relies on many human factors. Transcription, maintaining/cleaning, and sample preparation directly contribute to the quality of the analysis. A hidden cost of manual titration is the overuse of analyte, or over titration.
Regardless of the higher initial expense, there are numerous key considerations that would direct a user towards an automated solution. Manual titration is used approximately 60% of the time, but automated titration is increasing in popularity due to many main benefits, one of which explains that a completely automated system provides improved accuracy, safety, repeatability, traceability, and it meets regulatory requirements whilst giving employees more free time to spend in other valuable ways.
Enhanced Accuracy and Repeatability
Automated titration uses an extremely precise, motor-driven piston burette to dose titrant in tremendously small increments, for example, 0.001 mL. The piston burettes are tested to the ISO 8655 to confirm accuracy and reproducibility during manufacturing.
Table 1. Maximum permissible errors for motor-driven piston burettes. Source: YSI
Data-Based Detection of End-Equivalence Point
The results of automated titration are based on electrochemical measurements from a nominated electrode, rather than relying on a technician to identify a color change from a color indicator.
Inflection Point and Equivalence Point with a Suitable Indicator. Image Credit: YSI
Reliable Traceability of Results
Traceability of all titration leads to internal memory or connection with PC software. This means the data is easily transferable via a USB or the software connection. Capabilities give the opportunity to have full audit trails with optional CFR compliant Titrosoft software.
Image Credit: YSI
This burette needs minimal contact with potentially corrosive and harmful titrants and practically removes broken glassware.
Image Credit: YSI
Valuable Time is Gained
Automated titration gives technicians the opportunity to complete more tasks in one day by giving them more freedom from routine and time-consuming manual titrations. The addition of autosamplers for high throughput facilities can automate more than 40 samples at one time. Operating manual titrations and becoming an expert in this field can take several years, whereas automated titration requires employees of any skill level because they can be trained easily to perform a titration.
The improved efficiency and accuracy of automated instrumentation leads to more progressively obsolete manual titrations. In addition, as there is an increase in regulatory requirements and audits become more routine, the expense of continuing to complete manual titrations will outweigh the cost of upgrading a lab to an automated system.
This information has been sourced, reviewed and adapted from materials provided by YSI.
For more information on this source, please visit YSI.