Pharmaceutical and personal care products (PPCPs) such as household cleaning products, cosmetics and human and veterinary medicines are utilized for personal health or cosmetic reasons. The health impact on humans and the environment caused by PPCPs present in the environmental and potable water is a major concern (Figure 1). Hence, stringent monitoring of PPCPs is carried out by environmental regulatory bodies such as the US EPA.
Figure 1. The presence of PPCPs in environmental water and nearby soil is a widespread concern.
Detection of PPCPs is conventionally a complex process because of the potential presence of a range of substances. This article presents the results of a case study involving the use of a Bruker EVOQ triple quadrupole liquid chromatography mass spectrometer (LC-MS/MS) to show a more convenient yet robust method.
PPCP Detection
Traditional PPCP detection techniques have followed the US EPA 1694 method for analysis, which involves the pre-concentration of large volume water samples and laborious solid phase extraction (SPE) clean-up and the subsequent liquid chromatography mass spectrometry analysis to realize the low ng/L (ppt) level detection required for compliance with regulations.
In this study, Bruker devised a new technique involving the use of the Bruker Advance Ultra-high Performance Liquid Chromatography (UHPLC) system equipped with highly sensitive EVOQ LC-MS technology. PPCPs were detected at a level down to 1-2ppt with a linear response of up to 200 or 500ppt. Remarkable system robustness was achieved across the extended method development and sample analysis.
Case Study
The study was performed utilizing UHPLC with an integrated on-line extraction option integrated to the EVOQ. The integration of OLE facilitates method-driven on-line sample clean-up or sample pre-concentration. The study involved the analysis of several water samples for a range of PPCP species, including tap water samples, bottled and creek water. The sample analysis targeted a broad range of PPCP species that represented compounds exhibiting different concentrations and properties. The instrument calibrations used are summarized in Tables 1a and 1b.
Table 1a and 1b. Instrument set up for analysis of PPCPs in clean water.
Mass spectrometer parameters (EVOQ Elite) |
HV |
4000V |
Cone gas flow |
15 units |
Cone gas temperature |
300°C |
Heated probe gas flow |
40 units |
Heated probe temperature |
450°C |
Nebulizer gas flow |
50 units |
Exhaust gas |
On |
Q2 pressure |
1.5mTorr (Argon) |
Chromatography parameters (Advance UHPLC) |
Trap column |
YMC-Pack ODS-AQ, 3µm, 35mm x 2.0mm I.D. |
Column temperature |
40°C |
Injection volume |
400µL |
Flow rate |
400µL/min |
Solvent A |
2mM ammonium formate, 0.1% FA in water |
Solvent B |
2mM ammonium formate, 0.1% FA in MeOH |
Solvent C |
2mM ammonium formate, 0.1% FA in water |
Gradient conditions |
0.0 min, 10% B
0.2 min, 10% B
0.8 min, 25% B
8.0 min, 95% B
9.0 min, 95% B
9.1 min, 10% B
12.0 min, 10% B |
All of the PPCPs analyzed were detected at a level of 2ppt or better with an injection of 0.4mL water samples. The linear response range is up to 200 or 500ppt with r2 > 0.994. The injections replicated with 5ppt level spiked in tap water also showed robustness of the new method. Table 2 summarizes the results for the analysis of tap, creek and bottled water samples.
Table 2. Test results for selected PPCPs in real water samples.
Compound Name |
Tap Water 1 |
Tap Water 2 |
Creek Water |
Bottle Water |
Trimethoprim |
<2 |
<2 |
5 |
<2 |
Hydroxy Atrazine |
4 |
<2 |
7 |
<2 |
Thiabendazole |
ND |
<2 |
<2 |
<2 |
Ciproxacin |
ND |
ND |
ND |
ND |
Caffeine |
ND |
<2 |
<2 |
10 |
Sildenafil |
ND |
ND |
ND |
<2 |
Sulfamethoxazole |
<2 |
<2 |
ND |
<2 |
Cyanazine |
ND |
ND |
ND |
<2 |
Simazine |
3 |
<2 |
5 |
ND |
Metribuzin |
ND |
ND |
ND |
ND |
Hexazinone |
17 |
3 |
3 |
ND |
Dapoxetine |
ND |
ND |
ND |
ND |
Bentazone |
ND |
ND |
ND |
ND |
Ametryn |
ND |
ND |
<2 |
ND |
Carboxine |
ND |
ND |
ND |
ND |
Carbamazepine |
<2 |
<2 |
<2 |
ND |
Atrazine |
<2 |
ND |
ND |
ND |
Alpazolam |
ND |
ND |
ND |
ND |
Diuron |
9 |
<2 |
6.2 |
ND |
Prometryn |
ND |
ND |
ND |
<2 |
2,4-D |
9 |
<2 |
13 |
<2 |
MCPA |
<2 |
<2 |
<2 |
ND |
Mecoprop |
<2 |
<2 |
11 |
2 |
Metolachlor |
22 |
<2 |
<2 |
<2 |
Pyriproxifen |
ND |
<2 |
ND |
<2 |
Conclusion
Bruker’s EVOQ showed unprecedented detection limits and repeatability for all PPCPs analyzed, revealing numerous hardware innovations in the ion source like the Active Exhaust. This is complemented by unique PACER software, which provides reliable results in the quickest sample-to-report time possible.
The Bruker Advance UHPLC with OLE integrated to EVOQ LC-MS/MS enabled PPCP detection at 2ppt or better within 0.4mL samples. The technique provides a more convenient yet still robust PPCP analysis method when compared to traditional SPE-based techniques. The study also demonstrated the suitability of the EVOQ for analyzing multiple complex samples in high throughput laboratories, such as those performing environmental monitoring.
This information has been sourced, reviewed and adapted from materials provided by Bruker Life Sciences Mass Spectrometry.
For more information on this source, please visit Bruker Life Sciences Mass Spectrometry.