Automation in chemical analysis-need,objectives,instrumentation and process control analysis
- 1. 10-12-2021 1 Automation In Chemical Analysis One of the major developments in analytical chemistry during the last few decades has been the appearance of commercial automated analytical systems, which provide analytical and control information with a minimum of operator intervention. Automated systems first appeared in clinical laboratories, where thirty or more species are routinely determined for diagnostic and screening purposes. Laboratory automation soon spread to industrial process control and later to pharmaceutical, environmental, forensic, governmental, and university research laboratories. Today, many routine determinations as well as many of the most demanding analyses are made with totally or partially automated systems. Definition of Automation “IUPAC defines automation as the use of combination of mechanical and instrumental devices to replace, refine, extend or supplement human effort and facilities in the performance of a given process, which at least one major operation is controlled without human intervention by a feedback mechanism.”
- 2. 10-12-2021 2 Need for Automation • One of the most important reasons for automation is reproducibility, since mechanisms are operated by computers all processes can be repeated over and over without mistakes. • Speed of analysis –automated step can analysis up to 120 samples an hour which is far greater number than any human can achieve. • Due to this speed and number efficiency of analysis increases which reduces the cost of processes. • Since machines have more precise control smaller amount of sample is required along with less amount of reagents. • This reduced amount of sample and reagents reduces the cost even more and shifts analysis towards principles of green chemistry. • Automation also reduces the chances of contamination since there is minimum intervention. • All the data is automatically recorded and processes which reduces errors during transfer and give final result. • Automation also helps to meet the increasingly stricter demands of labs ,pharmaceuticals and government norms.
- 3. 10-12-2021 3 • Following chart chows most common steps in analysis and their possible automation by robotics.
- 4. 10-12-2021 4 Objectives of Automation • Facilitating an analytical technique or method. • Processing of large number of samples • Determination of several components in the same sample. • Reduction of human participation to- 1)Reduce or completely avoid errors. 2)Cut losses. • Increase sample throughput. • Process Control. • Lowering consumption of samples and reagents. • Deal with samples which are large in number or very valuable. • Analyse samples which sometimes are in low concentrations or dissimilar concentrations in sample .
- 5. 10-12-2021 5 Types of Automatic Analysis Technique. • Basically there are two types of automatic analysis techniques or instrumentations • Discrete sampling instrument • In discrete sampling, each sample undergoes reaction and measurement in separate cuvet or chamber. • These samples may be analysed sequentially or parallelly. • Continuous sampling instrument • In continuous flow sampling, the samples flow sequentially and continuously in tube perhaps being separated by air bubble. • They are each sequentially mixed with reagent in the same time at the sample point down stream and then flow sequentially into detector.
- 6. 10-12-2021 6 Flow Injection Analysis • Flow injection methods were first described by Ruzicka and Hansen in Denmark and Stewart and coworkers in the United States in the mid-1970s. • FIA is like a HPLC without a column.it is low pressure and without separation. The injected sample mixes and reacts with the flowing stream. • The sample and reagents are pumped with help of peristaltic pump. • First the sample is pumped out from source then the sample moves though flexible rubber tubing towards mixing coil 1. • Here the sample reagent is pumped from reservoir and sample and reagent mix with each other • Then this moisture moves towards next mixing coil where second reagent is pumped. • Here again the mixture reacts with second reagent and moves towards spectrometer. • Once analyte is passed through spectrometer reading is generated which is recorded via software. • After spectrometer the analyte removed through waste piping and spectrometer is ready for next sample.
- 7. 10-12-2021 7 • FIA can analyse up to 300 samples per hour giving tremendous speed and efficiency.
- 8. 10-12-2021 8 Discrete Automated Systems • These devices are designed to perform one or more of the unit operations given in others are capable of carrying out an entire analysis. • Some discrete systems are intended for a specific analysis only—for example, the determination of nitrogen in organic compounds or the determination of glucose in blood. • While Others can perform a variety of analyses of a given general type. For example, several automatic titrators can perform neutralization, precipitation, complex formation, and oxidation-reduction titrations as directed by a user- programmed computer. • Auto triter is an example of discrete system.