Effect of temperature programming and compound chemistry in.pptx

TEMPERATURE PROGRAMMING ON GAS CHROMATOGRAPHY

1. Effect of temperature programming and compound chemistry in Gas Chromatography NAME: MOLOY ROY COURSE: M.PHARM(1 ST YEAR) ROLL NO:2214063 PHARMACEUTICAL ANALYSIS DR.B.C ROY COLLEGE OF PHARMACY AND ALLIED HEALTH SCIENCE, DURGAPUR, WESTBENGAL 1

2. CONTENT What is Gas Chromatography(GC)? Instrumentation of GC and relevant problem arise with the constant temperature : What is temperature programming in Gas Chromatography?? And why it is needed.. Graphical representation of PTGC Reference 2 TOPIC SLIDE NUMBER 3-3 4-4 5-5 6-6 8-8

3. What is Gas Chromatography(GC)? Separation techniques used as analytical purpose in pharmaceutical industries. Used for the separation of volatiles substances and can easily transformed in to gaseous form Two types –(based on stationary phase) 1. Gas-liquid (GLC) stationary phase – liquid, mobile phase-gas. 2. Gas -solid (GSC) stationary phase- solid, mobile phase- gas Principle ADSORPTION PARTITION BASED ON INTERMOLECULAR FORCES BETWEEN adsorbate (sample to be analyzed) AND adsorbent(stationary phase) Ex: chlorophyll and xanthophyll separation is the first experiment of chromatography A SOLUTE WILL DISTRIBUTE ITSELF BETWEEN TWO IMMISCIBLE LIQUIDS ACCORDING TO ITS PARTITION COEFFICIENT. Ex: lower fatty acid experiment was the first GC experiment 3

4. Instrumentation of GC and Relevant problem arise with constant temperature : Image Source:  Bitesize Bio https://microbenotes.com/gas-chromatography/ Column thermostatically controlled oven (Mobile phase) Liquid/gas (in gaseous phase Incase of constant temperature problems are :- HIGHER TEMP: Poor resolution / Peaks are closely space (earlier elution ) LOWER TEMP: Peaks are broad ,widely spaced,excessive resolution Compound having high-boiling point are undetected due to immobility/ or stickiness to stationary phase .( late elution ) 4 Low boiling point compound or small sized particle eluted first and then highly boiling point or respectively larger sized particle compound was eluted

5. What is temperature programming in Gas Chromatography?? And why it temperature programming needed Temperature programming is the series of changing of temperature in column through out the analysis. It maintain the temperature through out the process of analysis. The programmed temperature process commonly consists of an initial isothermal period then liner temperature rise segment , then final isothermal period . But temperature programming may varies according to our need – high resolution of peak (slow rate ) or cut down the analysis time (rapid change). In temperature programming, those effects are overcome by maintaining a low temperature for a short period of time, and increasing the temperature to help force out the longer-‘sticking’ compounds.  This changes the retention time compared to a isothermal run. 5 Temperature programming is basically necessary to get the better result along with the specific time of analysis

6. EXAMPLE OF PTGC- SEPERATION OF CAFFEINE 6 http://svmsl.chem.cmu.edu/vmsl/Caffeine/caffeine_temperature.htm

7. Graphical represention of PTGC 7 30ºC/Min ; 40ºC 5ºC/Min ; 40ºC 75ºC ; CONSTANT TEMPERATURE

8. 8 REFERENCE https://chem.libretexts.org/Courses/BethuneCookman_University/B-CU%3A_CH-345_Quantitative_Analysis/Book%3A_Analytical_Chemistry_2.1_(Harvey)/12%3A_Chromatographic_and_Electrophoretic_Methods/12.04%3A_Gas_Chromatography (accessed on 06/11/2022 11:19 am) http://svmsl.chem.cmu.edu/vmsl/Caffeine/caffeine_temperature.htm (accessed on 05/11/2022 08:20pm) VOGEL’S TEXT BOOK OF QUANTITATIVE CHEMICAL ANALYSIS, 6 TH EDITION; CHAPTER 9; 272-291