The DART QDa System can provide a rapid screening technique for suspect supplements or over the counter medicines (OTCs). The DART QDa System was able to detect multiple, undeclared, active pharmaceutical ingredients within supplements purchased online, in multiple dosage forms (i.e., tablets, powders, and honey).
Dietary supplements are used by millions of consumers to improve health, maintain wellness, or support a more challenging lifestyle. Some of these supplements address conditions that many regard as shameful, awkward, or otherwise difficult to discuss with a physician. These conditions can include sexual dysfunction or excessive weight gain.1
Often, consumers choose supplements because they want a safe and natural alternative to drugs that are contraindicated for health reasons such as a heart condition. An example that illustrates this situation is that, almost exclusively, erectile dysfunction medication approved by the FDA are phosphodiesterase type 5 (PDE5) enzyme inhibitors,2 such as Sildenafil (Viagra, Pfizer), which can be fatal when taken with nitrate vasodilators (e.g., nitroglycerin).
DART (Direct Analysis in Real Time) by IonSense is an ambient ionization technique that allows for quick sampling of compounds without sample surface contact. This ionization technique, combined with the Waters ACQUITY QDa Mass Detector, enables a rapid, sample preparation-free technique for sample screening. The system further generates easy-to-interpret mass spectral information in seconds.
This application note shows the utilization of the DART QDa System for the direct analysis of a variety of online dietary supplements that are claimed to be 100% herbal treatments for a variety of conditions including impotence, obesity, and rheumatism. All but one of the examples were cited as containing undeclared pharmaceutical ingredients on the FDA website. Here we were able to show the detection of undeclared compounds in all cases. Further, we show that by inducing in-source fragmentation, we were able to produce additional specificity to aid in compound identification.
The following samples were analyzed:
Table 1. Analyzed herbal supplements and the suspected undeclared pharmaceutically active compounds with potential contraindications.
*Detailed on FDA website.
Sample introduction techniques employed:
Initially, direct analysis was attempted for the honey; however, the matrix complexity resulted in spectra dominated by compounds native to the honey.
A simple “solvent swap” sample preparation was devised by measuring approximately 2 mL of the honey and adding 2 mL of tertiary butyl ether. The container was shaken vigorously for a few seconds, and the supernatant was spotted onto the QuickStrip card for analysis (Figure 3).
The polar compounds, such as saccharides contained in honey, are immiscible with the highly hydrophobic ether removing the vast majority of matrix interference from the honey. Analysis of the supernatant at 450 °C using a 5 V cone voltage shows spectra consistent with the erectile dysfunction drug Tadalafil (m/z 390) when compared with Tadalafil standard (Figure 4). Increasing the cone voltage to 50 V induces similar fragmentation patterns for both the Tadalafil standard and the honey supernatant (m/z 135, 268).
A Nuvitra capsule was split and a small amount of the contents were applied to an OpenSpot card which was directly introduced to DART (Figure 5). The method was initially run using a DART temperature of 200 °C with a QDa cone voltage of 5 V. Increasing the temperature to 250 °C promoted the ionization of fluoxetine while inducing fragmentation of both fluoxitine and sibutramine (fragments at m/z 125 and 195, respectively [Figure 6]).
Ortiga joint remedy tablets are uncoated and therefore can be introduced directly to the DART source using the DART tablet holder and linear rail. Ten separate tablets were analyzed in Figure 7.
The FDA website states that Ortiga tablets are suspected to contain the NSAID (nonsteroidal anti-inflammatory drug) dicolfenac (m/z 296). Tablet analysis indicated that diclofenac was not present (Figure 8). The tablet analysis gave a base peak signal at m/z 152 which does correspond to the molecular ion of acetaminophen. When compared to the acetaminophen standard, both standards produced fragments at m/z 110 indicating the loss of the acetyl group of acetaminophens.
The DART QDa System can provide a rapid screening technique for suspect supplements or over the counter medicines (OTCs). This may be routinely performed using library matching or profile matching software.
The DART QDa System was able to detect multiple, undeclared, active, pharmaceutical ingredients within supplements purchased online, in multiple dosage forms (i.e., tablets, powders, and honey).
By utilizing in-source fragmentation with the QDa, and temperature manipulation of the DART helium gas stream, more information was derived from the sample in terms of specificity.
The discrepancy between the suspected, undeclared compound and the compounds detected in Ortiga joint remedy serves to highlight the lack of consistency and responsibility of the producers of these products, and the need to rapidly screen these products for consumer protection.
High resolution mass spectrometry (HRMS) would still be required for full spectral confirmation; however, the specificity provided by the single quadrupole detector will decrease the likelihood of false positives.
720006603, August 2019