BCIT Citations Collection | BCIT Institutional Repository

BCIT Citations Collection

AOAC SMPR® 2016.013
AOAC SMPR® 2016.013 Standard Method Performance Requirements (SMPRs) for Identification and Quantitation of Animal-Derived Proteins in Dietary Supplements. The article presents a study that determines the standard method performance requirements (SMPRs) for identifying and quantifying animal-derived proteins in dietary supplements. It offers overview of the purpose, applicability, and definitions involved in the study. It also outlines the result of the system suitability, validation guidance and potential reference of the study., Peer-reviewed article, Published.
AOAC SMPR® 2016.014
AOAC SMPR® 2016.014 Standard Method Performance Requirements (SMPRs) for Identification and Quantitation of Non-Animal-Derived Proteins in Dietary Supplements. The article presents a study that determines the standard method performance requirements (SMPRs) for determining and quantifying non-animal-derived proteins in dietary supplements. It offers overview of the purpose, applicability of the methods, and definitions involved in the study. The also outlines the system suitability tests, validation guidance, and potential references of the study., Peer-reviewed article, Published.
AOAC SMPR® 2016.015
The article presents a study that determines the standard method performance requirements (SMPRs) in identifying animal-derived proteins in dietary supplements. It offers overview of the purpose, applicability, and method performance requirements used in the study. It also outlines the system suitability, potential reference materials, and validation guidance of the study., Peer-reviewed article, Published.
AOAC SMPR® 2016.016
The article presents a study that determines the standard method performance requirements (SMPRs) for determining non-animal-derived proteins in dietary supplements. It offers overview of the purpose, applicability of the methods, and definitions involved in the study. The also outlines the system suitability tests, validation guidance, and potential references of the study., Peer-reviewed article, Published.
Curcuminoids in turmeric roots and supplements
Curcuma longa L. rhizomes are used extensively as a spice in food preparations and dietary supplements for their anti-inflammatory and antioxidant properties. An expert review panel (ERP) evaluated analytical methods for the quantitation of individual curcuminoids for the purpose of identifying a method for official method status. It was requested that several modifications be undertaken to improve method performance prior to subjecting the chosen method to a single-laboratory validation. Two separate Plackett-Burman factorial studies were used to identify factors that contributed to the chromatographic separation and extraction of curcuminoids. Significant factors were further optimized to produce the improved HPLC method for curcuminoid separation. This method was then subjected to a single-laboratory validation according to the AOAC International guidelines for linearity, detection limits, precision, and accuracy. The two most significant factors impacting the quantitation of curcuminoids were column temperature and extraction solvent, which were optimized to 55 °C and 100 % methanol, respectively. The validation was performed on 12 raw materials and finished products containing turmeric roots. The method precision was reported using HorRat values which were within recommended ranges of the AOAC guidelines. Overall accuracy of the method was accessed at three separate levels for each analyte and ranged from 99.3–100.9 %. The validated method is suitable for quantitation of individual curcuminoids in turmeric raw materials and finished products and is recommended for consideration as an official method by the AOAC International., Peer-reviewed article, Published. Received 13 July 2015; Accepted 21 September 2015; Published online 29 September 2015.
Current initiatives for the validation of analytical methods for botanicals
The demand for validated analytical methods for botanicals has grown in response to the increasing consumer market for botanical supplements. Government initiatives to increase the availability of validated analytical methods and botanical reference material have led to the publication of numerous validation studies in scientific journals. Single laboratory validation and collaborative validation studies are structured to confirm a method's ruggedness and fit for purpose. The performance characteristics and statistical protocols followed throughout a validation study vary with the source of guidelines. Analytical techniques and priority methods are influenced by the need for fast-screening techniques, the limited availability of reference material, market value, and the prevalence of contaminants in botanical supplements., Peer-reviewed article, Published.
Determination of hydrastine and berberine in goldenseal raw materials, extracts, and dietary supplements by high-performance liquid chromatography with UV
A multilaboratory collaborative study was conducted on a high-performance liquid chromatographic (HPLC) method utilizing UV detection, previously validated using AOAC single-laboratory validation guidelines for determination of hydrastine and berberine in goldenseal (Hydrastis canadensis L.) raw materials, extracts, and dietary supplements at levels ranging from 0.4 to 6% (w/w). Nine collaborating laboratories determined the hydrastine and berberine content in 8 blind samples. Sample materials included powdered botanical raw materials, whole root material, and 4 finished product dietary supplements containing either goldenseal powdered root material or extract. The materials were extracted with an acidified water and acetonitrile solution. HPLC analyses of the extracts were performed on a C18 column using UV detection at 230 nm. Results for powdered root material and capsule products ranged from about 0.2% (w/w) for each alkaloid to about 4% (w/w) for each alkaloid. Liquid tincture results were approximately 4000-5000 microg/mL for each alkaloid. Reproducibility relative standard deviations (RSDR) for hydrastine ranged from 2.68 to 6.65%, with HorRat values ranging from 0.77 to 1.89. RSDR for berberine ranged from 5.66 to 7.68%, with HorRat values ranging from 1.32 to 2.12. All finished products containing goldenseal extract yielded HorRat values <2.0. Based on these results, the method is recommended for Official First Action for determination of hydrastine and berberine in goldenseal raw materials and dietary supplement finished products containing powdered goldenseal and goldenseal extract., Peer-reviewed article, Published.
Determination of phenolic constituents in echinacea raw materials and dietary supplements by HPLC-UV
A collaborative study was conducted to evaluate an HPLC method for determining phenolic compounds in Echinacea spp. raw materials, powdered extracts, and tinctures. Eleven collaborating laboratories received three practice samples representing each matrix type, phenolic reference standards, eight test samples as blind duplicates, the validated analytical method, and instructions. Test samples included two raw materials, four extracts (including one in combination with astragalus and reishi), one ethanolic tincture in combination with goldenseal, and one glycerite tincture. Each material was extracted with a 60% methanol aqueous solution, separated on a C18 column, and detected at 330 nm. Results reported by laboratories for total phenolics in Echinacea roots, aerial parts, and extracts ranged from 9.5 to 62.9 mg/g with RSDR ranging from 3.64 and 7.95% and Horwitz ratio (HorRat) values ranging from 1.06 to 2.01. Total phenolics in the ethanolic tincture ranged from 4837 to 5962 μg/mL, with an RSDR of 6.35% and a HorRat value of 1.45. The glycerite tincture showed poor interlaboratory precision with a HorRat value of 3.32, an RSDR of 21.8%, and reported total phenolic values ranging from 257 to 539 μg/mL., Peer-reviewed article, Published. Received May 4, 2016; Accepted by AP May 25, 2016.
The importance of method selection in determining product integrity for nutrition research
The American Herbal Products Association estimates that there as many as 3000 plant species in commerce. The FDA estimates that there are about 85,000 dietary supplement products in the marketplace. The pace of product innovation far exceeds that of analytical methods development and validation, with new ingredients, matrixes, and combinations resulting in an analytical community that has been unable to keep up. This has led to a lack of validated analytical methods for dietary supplements and to inappropriate method selection where methods do exist. Only after rigorous validation procedures to ensure that methods are fit for purpose should they be used in a routine setting to verify product authenticity and quality. By following systematic procedures and establishing performance requirements for analytical methods before method development and validation, methods can be developed that are both valid and fit for purpose. This review summarizes advances in method selection, development, and validation regarding herbal supplement analysis and provides several documented examples of inappropriate method selection and application., Peer-reviewed article, Published.
Optimization and single-laboratory validation of a method for the determination of flavonolignans in milk thistle seeds by high-performance liquid chromatography with ultraviolet detection
Seeds of milk thistle, Silybum marianum (L.) Gaertn., are used for treatment and prevention of liver disorders and were identified as a high priority ingredient requiring a validated analytical method. An AOAC International expert panel reviewed existing methods and made recommendations concerning method optimization prior to validation. A series of extraction and separation studies were undertaken on the selected method for determining flavonolignans from milk thistle seeds and finished products to address the review panel recommendations. Once optimized, a single-laboratory validation study was conducted. The method was assessed for repeatability, accuracy, selectivity, LOD, LOQ, analyte stability, and linearity. Flavonolignan content ranged from 1.40 to 52.86 % in raw materials and dry finished products and ranged from 36.16 to 1570.7 μg/mL in liquid tinctures. Repeatability for the individual flavonolignans in raw materials and finished products ranged from 1.03 to 9.88 % RSD, with HorRat values between 0.21 and 1.55. Calibration curves for all flavonolignan concentrations had correlation coefficients of >99.8 %. The LODs for the flavonolignans ranged from 0.20 to 0.48 μg/mL at 288 nm. Based on the results of this single-laboratory validation, this method is suitable for the quantitation of the six major flavonolignans in milk thistle raw materials and finished products, as well as multicomponent products containing dandelion, schizandra berry, and artichoke extracts. It is recommended that this method be adopted as First Action Official Method status by AOAC International., Peer-reviewed article, Published. Received 1 June 2015; Revised 14 July 2015; Accepted 16 July 2015; Published online 31 July 2015.