Cannabis Analysis

Brian C. Smith
Brian C. Smith, PhD, is Founder, CEO, and Chief Technical Officer of Big Sur Scientific in Capitola, California. The “Cannabis Analysis” column introduces the cannabis industry to the basic concepts of analytical chemistry. Seasoned scientists will also benefit from reading this column because it provides a refresher on important basic topics, introduces instrumental techniques they might not be familiar with, and is a place to discover new applications.

Calibration Science, Part II: Systematic Error, Signal-to-Noise Ratios, and How to Reduce Random Error

February 24, 2024

Here, we will introduce systematic error, discuss how to measure signal-to-noise ratios, and more.

Calibration Science, Part I: Precision, Accuracy, and Random Error

December 13, 2023

Here, we begin a new column series on calibration science. The goal of these columns will be to teach you the foundational theory behind how to calibrate analytical instruments that are used for quantitative analysis in the cannabis analysis industry, such as potency and pesticide analyzers.

The Ongoing Myth of Potency Accuracy in Cannabis Analysis

October 17, 2023

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

Chromatography Theory, Part VIII: Pulling It All Together

September 27, 2023

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

Chromatographic Theory, Part VII: The Master Chromatographic Resolution Equation

August 24, 2023

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 VI: Peak Widths, Band Spreading, and Plate Number

June 20, 2023

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

Chromatographic Theory, Part V: Chromatographic Resolution

May 19, 2023

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 IV: Measuring Separation Quality with Capacity and Separation Factors

April 07, 2023

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.

Chromatography Theory, Part III: Calculating Elution Times and Capacity Factors

March 03, 2023

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.

Chromatography Theory, Part II: How Separations Occur Illustrated and Quantitated

February 01, 2023

Part II of this series looks at the mechanism via which molecules move through HPLC columns and leads us to a discussion on the equations used to characterize separations.