What does HPLC stand for?

HPLC stands for High-Performance Liquid Chromatography. The technique was originally called High-Pressure Liquid Chromatography because it uses high pressure to push the mobile phase through the packed column.

Why is HPLC the standard for kratom alkaloid analysis?

HPLC reliably separates the principal kratom alkaloids - including mitragynine and 7-hydroxymitragynine - from each other and from matrix components, and it provides quantitative assay values that can be verified against certified reference standards. The technique is well established in the United States Pharmacopeia and ICH guidelines.

What detector is used for HPLC of kratom alkaloids?

The most common detector is ultraviolet-visible absorbance, often at a wavelength near 226 nm. Mass spectrometry (LC-MS/MS or LC-HRMS) is paired with HPLC to confirm peak identity.

Where do HPLC results appear in a 7-OH product workflow?

On the Certificate of Analysis. Every reputable 7-OH product batch is accompanied by a COA that lists the HPLC-measured percent-assay of mitragynine and 7-hydroxymitragynine.

What is the difference between HPLC and LC-MS?

HPLC is the separation technique. LC-MS is HPLC paired with a mass-spectrometer detector. LC-MS provides additional information about peak identity (mass-to-charge ratio and fragmentation pattern) that UV detection alone does not.

Lab Testing & Quality

HPLC (High-Performance Liquid Chromatography)

At-a-glance comparison

Spec	Value
Full name	High-Performance Liquid Chromatography
Earlier name	High-Pressure Liquid Chromatography
Common variant for kratom analysis	Reverse-phase HPLC with C18 column
Common detectors	UV-Vis (often at 226 nm for kratom alkaloids); mass spectrometry (LC-MS/MS or LC-HRMS) for confirmation
Quantitative output	Peak area at known retention time, calibrated against reference standards
Typical 7-OH and mitragynine retention times	Method-dependent; verified against certified reference standards
Standards reference	USP <621> Chromatography; ICH Q2(R1) for validation
Where it appears in your workflow	On every Certificate of Analysis for kratom and 7-OH products

What is HPLC?

High-Performance Liquid Chromatography is an analytical technique that separates the components of a liquid mixture by passing them through a packed column under high pressure. Different compounds in the mixture interact differently with the stationary phase inside the column and travel through it at different speeds, emerging at different retention times. A detector at the column outlet records when each compound emerges, producing a chromatogram in which each peak corresponds to one compound and the area under the peak corresponds to its concentration.

HPLC is the workhorse analytical method across pharmaceuticals, food chemistry, environmental analysis, and botanical products. For kratom and 7-OH products, it is the standard method for measuring percent-assay of mitragynine and 7-hydroxymitragynine.

How HPLC measures kratom alkaloids

For kratom and 7-OH analysis, the most common HPLC configuration is reverse-phase, in which the column packing is non-polar (typically a C18 silica) and the mobile phase is a polar solvent system such as acetonitrile or methanol mixed with aqueous buffer. The kratom alkaloids elute from the column at characteristic retention times that depend on the specific column, mobile phase, and gradient program used.

Detection is typically by ultraviolet absorbance, often at a wavelength near 226 nm where mitragynine and 7-OH absorb strongly. Quantification uses an external calibration curve built from certified reference standards of mitragynine and 7-hydroxymitragynine. The peak area for each alkaloid in the sample chromatogram is interpolated against the calibration curve to yield the percent-assay value reported on the Certificate of Analysis.

Why HPLC results are paired with mass spectrometry

HPLC with UV detection alone identifies a peak by retention time and quantifies it by absorbance. However, retention time is not unique - multiple compounds can elute at similar times, and a peak that looks like 7-OH could in principle be something else. To confirm peak identity, analysts pair HPLC with mass spectrometry detection (LC-MS/MS or LC-HRMS), which characterizes each peak by its mass-to-charge ratio and fragmentation pattern. 7-OH gives an [M+H]+ ion at m/z 415 with characteristic fragments.

A complete and credible analytical workflow for a 7-OH product therefore typically includes HPLC for quantification and mass spectrometry for identity confirmation. Both results are reported on the Certificate of Analysis.

Method validation

An analytical method used for product release must be validated. The International Council for Harmonisation Q2(R1) guideline defines the validation parameters: specificity (the method discriminates the analyte from all other components), linearity (the response is proportional to concentration over a defined range), accuracy, precision, range, detection limit, quantitation limit, robustness, and system suitability.

United States Pharmacopeia chapter provides the framework for chromatographic system suitability testing. Reputable laboratories will have validated the specific method they use for kratom alkaloid quantification, and the method validation summary is available on request from the lab.

Common questions about hplc (high-performance liquid chromatography)

What does HPLC stand for?: HPLC stands for High-Performance Liquid Chromatography. The technique was originally called High-Pressure Liquid Chromatography because it uses high pressure to push the mobile phase through the packed column.
Why is HPLC the standard for kratom alkaloid analysis?: HPLC reliably separates the principal kratom alkaloids - including mitragynine and 7-hydroxymitragynine - from each other and from matrix components, and it provides quantitative assay values that can be verified against certified reference standards. The technique is well established in the United States Pharmacopeia and ICH guidelines.
What detector is used for HPLC of kratom alkaloids?: The most common detector is ultraviolet-visible absorbance, often at a wavelength near 226 nm. Mass spectrometry (LC-MS/MS or LC-HRMS) is paired with HPLC to confirm peak identity.
Where do HPLC results appear in a 7-OH product workflow?: On the Certificate of Analysis. Every reputable 7-OH product batch is accompanied by a COA that lists the HPLC-measured percent-assay of mitragynine and 7-hydroxymitragynine.
What is the difference between HPLC and LC-MS?: HPLC is the separation technique. LC-MS is HPLC paired with a mass-spectrometer detector. LC-MS provides additional information about peak identity (mass-to-charge ratio and fragmentation pattern) that UV detection alone does not.
What is reverse-phase HPLC?: Reverse-phase is a chromatographic mode in which the column stationary phase is non-polar (typically C18 silica) and the mobile phase is a polar solvent system. It is the most widely used HPLC mode for small-molecule analysis, including kratom alkaloid analysis.

References

United States Pharmacopeia. (2024). General Chapter Chromatography.
International Council for Harmonisation. (2005). ICH Q2(R1) Validation of Analytical Procedures: Text and Methodology.
Brown PN, Lund JA, Murch SJ. (2017). A botanical, phytochemical and ethnomedicinal review of the genus Mitragyna korth. Journal of Ethnopharmacology.

Important safety information:

Products containing 7-hydroxymitragynine (7-OH) are sold for adult use only (21+). These statements have not been evaluated by the U.S. Food and Drug Administration. Products are not intended to diagnose, treat, cure, or prevent any disease. The FDA has raised safety concerns regarding concentrated 7-OH products; consult a qualified healthcare professional before use. Do not operate vehicles or machinery after use. Keep out of reach of children and pets. Laws vary by state, buyers are responsible for knowing applicable law.

Oops, your cart is still empty