Sexual Drug Adulterations Testing

As many of our customers have been aware, Amazon recently requires that all nutrition

supplements with an indication of sexual enhancement (or male drive) on its labels and

promotion marketing material are required to test for three erectile dysfunction (ED) drugs,

Sildenafil, Tadalafil and Vardenafil, and two analogs of the ED drugs: Sulfoaildenafil, and

Desmethyl carbodenafil in its testing program. A similar requirement for testing weight loss

drugs has also been in place.

MS Bioanalytical has been providing testing certificates to our customers for dietary

supplements since the Amazon program started early this year. We now provide certificates of

analysis for testing ED and weight-loss drugs. To meet the requirement of the Amazon program,

we use LC/MS/MS methods. Typical MS chromatograms are shown Figure 1. As can be seen the

standards of five ED drugs were separated with strong signals. The spikes of these drugs into the

sample were recovered well. None of the five drugs investigated was detected in the test sample.

Based on the test results, a Certificate of Analysis with “ND” (not detected) of these five drugs

along with all necessarily required elements, which includes our ISO-17025 accreditation

number and contact information is issued to our customers.

Figure 1. Typical LC-MS-MS graphs showing three chromatograms of each of the five drugs:

standard of the drug, sample, and sample with spike of the drug.

If we can be service to you to meet the requirement of the program or you have any question or

require additional information, please feel free to contact us.

New Requirements for Nutrition Products at Amazon

As Amazon is getting bigger and attacking more and more sellers of dietary supplements to its platform, new requirements will be implemented by February 2021. Once it is fully implemented, any dietary supplements sold on its platform that do not meet the new requirements shall be either removed from its site, and Amazon may suspend the seller from marketing products on Amazon, withhold payments to the seller, or even pursue legal action. These new requirements are:

• A Certificate of Analysis (CoA), from an ISO/IEC 17025 accredited laboratory. Each CoA must have been issued within the previous six months, be for product that is within its expiration date, and include the product’s name, batch/lot number, or date code of the product, name and address of the manufacturer or distributor, the name of each ingredient noted on the Supplement Facts Panel (SFP) along with quantitative analysis confirming that the product contains the amount of ingredients as noted in the SPF, and the units on the CoA matching the units as found in the SFP.

• Product images that must show all sides of the product label that include the name of the product, the name and address of the company, batch, lot number, or date code of the product and the SFP.

• A letter of guarantee from the manufacturer, on their letterhead the complete name of the product as it is represented in the product label and labeling; an assurance that the product has been properly manufactured under the Good Manufacturing Practices of 21 C.F.R. 111, an assurance that the product is not adulterated under Section 402(f) of the Federal Food, Drug, and Cosmetic Act and the assurance that the amount of ingredients in the product reflects what is represented in the SFP and is safe for consumption.

MS Bioanalytical is an FDA-registered and ISO-17025 accredited laboratory. Our service scope covers all areas of testing dietary supplements. Upon request, our CoA may be tailored to meet Amazon’s requirements with minimal cost for such CoA.

If you have any question or have additional requirements, please feel free to contact us at info@msbioanalytical.com, (217) 689-2969.

NADH Analysis by UPLC-UV

Nicotinamide adenine dinucleotide (NAD) is a coenzyme found in all living cells. The compound is a dinucleotide, because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine base and the other nicotinamide. NADH exists in two forms: an oxidized form and reduced form (NAD+ and NADH), respectively. This pair of coenzyme is involved in redox reactions, carrying electrons from one reaction to another (Figure 1). NAD+ accepts electrons from other molecules to become reduced form NADH. NADH passes its protons to an acceptor to become an oxidized from NAD+. This pairs of compounds plus another pair compounds NADP+ and NADPH by accepting and donating their electrons in an electron transport chains play important roles in energy formation, storage and usage during cellular biological process of cells.

The analysis of NADH and NAD+ may be carried out by a number of different methods. The first method is to use UV-VIS spectrophotometric method. In this method, the Absorbance of the assay solution is read at 340 nm. Because NADH has a maximum absorbance at 340 nm and little and no absorbance for NAD+. Based on the reading, we can calculate NADH concentration. By adding a reducing agent to the assay to reduce NAD+ to NADH, followed reading at 340 nm again, one can determine the difference of the two readings, which is considered as NAD+. This method does not require expensive equipment and simple and fast. However, when the sample contains compounds with absorbance at 340 nm, it would over estimate NADH concentration. If the system contains redox compounds, the conversion of NAD+ to NADH will also be interfered.

The second method is using fluorescence spectrophotometric method. This is similar to the UV—VIS Spectrophotometric method but using fluorescence detection. NADH has an excitation wavelength at 340 nm and emission at 460 nm. Setting the fluorescence allows us to reduce the interference of compounds that does not have such fluorescence characteristics. The method is also relatively simple, but it is often interfered by other compounds in the sample.

The third method is to use enzyme coupled assay using dehydrogenase. In this method, a system was set-up containing sufficient dehydrogenase (i.e., alcohol dehydrogenase and substrate (i.e., alcohols): Alcohols + NAD+ ⇌ Aldehydes + NADH + H+ . By monitoring the changes at 340 nm, one can determine the abundance (concentration) of NAD+/NADH in the reaction by comparing to a reference solution with known amount of references NAD+/NADH. This method is sensitive, but it is challenging to produce consistent results.

The fourth method is HPLC (UPLC)-UV method which we used in our recent assay. If the concentration is low or matrix is complex, UPLC/MS/MS method may be used. In the dietary supplement industry, the NADH products are mostly formulated with mg of NADH per dosage. A typical UPLC-UV chromatogram is shown in Figure 2. As can be seen, it is easy to determine NADH content when compared to reference standard NADH. Our validation of this method has indicated that the UPLC-UV method is accurate with average recovery of 100%, and precise with a relative deviation of 2.6% . The method is also specific with little and no interference.