Chromatography Techniques

Brian C. Smith, PhD, is Founder, CEO, and Chief Technical Officer of Big Sur Scientific. He is the inventor of the BSS series of patented mid-infrared based cannabis analyzers. Dr. Smith has done pioneering research and published numerous peer-reviewed papers on the application of mid-infrared spectroscopy to cannabis analysis, and sits on the editorial board of Cannabis Science and Technology. He has worked as a laboratory director for a cannabis extractor, as an analytical chemist for Waters Associates and PerkinElmer, and as an analytical instrument salesperson. He has more than 30 years of experience in chemical analysis and has written three books on the subject. Dr. Smith earned his PhD on physical chemistry from Dartmouth College. Direct correspondence to: 

Articles

It is impossible to obtain potency accuracy in cannabis analysis. Here, we suggest some solutions to the problem.

The Ongoing Myth of Potency Accuracy in Cannabis Analysis

Here, we explore how the different parameters in the Master Resolution Equation relate to Fs, and what that means for chromatographic experiments.

Chromatography Theory, Part VIII:  Pulling It All Together

We finally present the Master Resolution Equation for chromatography, which combines all three measures of separation quality, and an understanding of these parameters will go a long way towards allowing you to rationally develop chromatographic methods.

Chromatographic Theory, Part VII:  The Master Chromatographic Resolution Equation

Here we discuss diffusion and see how a quantity called plate number is used to measure the amount of band spreading.

Chromatographic Theory, Part VI:  Peak Widths, Band Spreading, and Plate Number

A review of the concept of separation factors and a discussion on developing a method for measuring peak width including triangulation followed by the introduction of the concept of chromatographic resolution for a pair of peaks.

Chromatographic Theory, Part V: Chromatographic Resolution

The current challenges and future perspectives of the purification of cannabinoids from cannabis extracts are presented in this review article.

Purification and Isolation of Cannabinoids: Current Challenges and Perspectives

A novel liquid chromatography–tandem mass spectrometry (LC–MS/MS) method with a dual electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) source was developed for analyzing 102 pesticides and five mycotoxins that are regulated by the state of Colorado in hemp.

Study: Tandem Mass Spectrometry Method for Analysis of 102 Pesticides and Five Mycotoxins Regulated by the State of Colorado in Dried Hemp

Don't miss this Noid Factoid from Dr. Julie Kowalski of JA Kowalski Science Support LLC.

Noid Factoid from Episode 14

Part IV of this series discusses the capacity factor of chromatographic peaks to calculate separation factors, whose value tells us how well two peaks are or aren’t separated. We then introduce the reality of peak widths and how they impact separation quality.

Chromatographic Theory, Part IV:  Measuring Separation Quality with Capacity and Separation Factors

Part III of this series will delve into understanding how to optimize methods for chromatographic separations, Smith will also introduce the concepts of capacity factor and selectivity.
