Elsevier

Talanta

Volume 74, Issue 5, 15 February 2008, Pages 1299-1312
Talanta

The effect of signal suppression and mobile phase composition on the simultaneous analysis of multiple classes of acidic/neutral pharmaceuticals and personal care products in surface water by solid-phase extraction and ultra performance liquid chromatography–negative electrospray tandem mass spectrometry

https://doi.org/10.1016/j.talanta.2007.08.037Get rights and content

Abstract

A new multi-residue method for the determination of 25 acidic/neutral pharmaceuticals (antibiotics, anti-inflammatory/analgesics, lipid regulating agents, diuretics, triazides, H2-receptor antagonists, cardiac glicozides and angiotensin II antagonists) and personal care products (sunscreen agents and preservatives) in surface water with the usage of a new technique: ultra performance liquid chromatography–negative electrospray tandem mass spectrometry (UPLC–MS/MS) was developed and validated. The novel UPLC system with 1.7 μm particle-packed column allowed for good resolution of analytes with the application of low mobile phase flow rates (0.05 mL min−1) and short retention times (from 4.7 min to 13.3 min) delivering a fast and cost-effective multi-residue method. SPE with the usage of Oasis MCX strong cation-exchange mixed-mode polymeric sorbent was chosen for sample clean-up and concentration. The influence of mobile-phase composition, matrix assisted ion suppression and SPE recovery on the sensitivity of the method was identified and quantified. The instrumental limits of quantification varied from 0.2 μg L−1 to 30 μg L−1. The method limits of quantification were at low nanogram per litre levels and ranged from 0.3 ng L−1 to 30 ng L−1. The instrumental and method intra-day and inter-day repeatabilities were on average less than 5%. The method was successfully applied for the determination of PPCPs in River Taff. Thirteen compounds were determined in river water at levels ranging from a single to a few hundred nanograms per litre. Among them were ten pharmaceuticals (aspirin, salicylic acid, ketoprofen, naproxen, diclofenac, ibuprofen, mefenamic acid, furosemide, sulfasalazine and valsartan) and three personal care products (methyl- and ethylparaben and 4-benzophenone).

Introduction

Pharmaceuticals and personal care products (PPCPs) are a group of emerging, potentially hazardous contaminants, which have, to date, received limited attention, although interest in this area is increasing considerably and the need for further investigation in this field is continuously emphasised by different research groups [1], [2], [3], [4], [5], [6]. PPCPs are found in surface water and wastewaters at levels of up to a few μg L−1 [1], [2], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [24], [25], [26], [27], [28], [29], [30]. They enter the aquatic environment mainly through treated (or raw) sewage from domestic households and hospitals, waste effluents from manufacturing processes and runoff. Domestic animals are the main direct source of the environmental disposal of many PPCPs such as veterinary pharmaceuticals. The other direct route from which PPCPs enter the environment is recreational activities. Many PPCPs are ubiquitous and persistent in the environment. Some are capable of bioconcentration and many of those investigated are biologically active compounds. Some are suspected, or are recognised to be, endocrine disruptors, which could potentially influence environmental and human health. Additionally, they are continuously introduced into the environment; therefore even compounds of a low persistence might cause adverse effects in human and aquatic life. The other issue is the synergic effect of different PPCPs on aquatic life, through their combined non-targeted action with many other biologically active compounds present in the environment [1], [2]. A few pharmaceuticals and personal care products have been determined in drinking water, which poses a direct risk to humans [2] and raises the issue of contaminated water sources and especially water reuse.

Due to growing concern regarding the presence, fate and effects on the environment and humans, there is an obvious need for fast and sensitive multi-residue methods for the determination of low levels of PPCPs in the environment. Traditional gas chromatography is of limited value in the case of polar (non-volatile) compounds as it requires time consuming derivatization procedures. Liquid chromatography–mass spectrometry (LC/MS) using mainly ESI (electrospray ionisation) is the method of choice for the analysis of polar compounds in complex matrices. So far, a few multi-residue analytical methods for the determination of PPCPs in the aqueous environment have been established [31], [32], [33], [34], [35], [36]. These methods utilise solid-phase extraction as a sample preparation method and almost exclusively liquid chromatography coupled with electrospray ionisation tandem mass spectrometry for separation and quantification of up to 30 compounds on C18 column with up to 50 min elution gradient time and average mobile phase flow rate of 0.2 mL min−1.

Here a new fast and sensitive method for the determination of a broad range of pharmaceuticals and personal care products is presented. The method uses a single SPE method and single LC/MS/MS method utilising UPLC™ (ultra performance liquid chromatography) coupled with triple quadruple tandem mass spectrometry. UPLC is a novel technology providing significant improvements in resolution, speed and sensitivity due to the exploitation of a 1.7 μm particle-packed column.

This paper presents a novel method for the analysis of 25 acidic/neutral pharmaceuticals and personal care products in surface water with the utilisation of SPE/UPLC/ESI-(negative ionisation)-MS-MS and demonstrates its application in the Welsh environment. The group of PPCPs of interest have never previously been studied in the Welsh aqueous environment, to the best knowledge of the authors. A previous paper published by the authors [37], presented another novel multi-residue method for the analysis of a further 28 basic/neutral pharmaceuticals and illicit drugs in surface water by means of SPE/UPLC/ESI+(positive ionisation)-MS-MS. The overall methodology published in the form of the two papers allows for the analysis of almost 50 PPCPs in surface water. The rationale for the preparation of two separate methods for the analysis of all PPCPs resulted from their different structures and physicochemical properties influencing both the composition of mobile phase used for analytes separation in LC and ionisation mode used in ESI-MS. Additionally, the paper identifies and quantifies the influence of matrix components on the performance of the analytical methods and presents possible ways to solve it.

Section snippets

Chemicals and materials

Reference standards (>95% purity) were purchased from Sigma–Aldrich (Gillingham, UK) and Sequoia Products Research Limited (Pangbourne, UK). All solvents used as mobile phases and their additives were of LC/MS quality. Surrogate/internal standards (IS): clofibric-d4 acid (4-chlorophenyl-d4), 3,4-dichlorobenzoic (2,5,6-d3) acid, bisphenol A-d16 and 4-chlorophenol (2,3,5,6-d4) were purchased from QMX Laboratories Limited (Essex, UK). All standards used as both surrogate and internal standards

Results and discussion

Seventeen pharmaceuticals and eight personal care products were the subject of the research (Table 1). The choice of pharmaceuticals was mainly based on the prescription data in Wales and England [39], [40] and the metabolism routes of pharmaceuticals, mainly excretion as parent compounds and active main metabolites. The choice of PCPs was based on their high annual usage in wide range of household products and concern over their possible effect on human and aquatic organisms [41].

Conclusions

This paper concerns the development and validation of a novel, fast and cost-effective multi-residue method for environmental monitoring of 25 acidic/neutral pharmaceuticals (antibiotics, anti-inflammatory/analgesics, lipid regulating agents, diuretics, triazides, H2-receptor antagonists, cardiac glicozides and angiotensin II antagonists) and personal care products (susnscreen agents and preservatives) in the low nanogram per litre range. The method involved single solid-phase extraction with

Acknowledgment

This work was undertaken as a part of the EU Marie Curie Host Fellowship for the Transfer of Knowledge (contract number MTKD-CT-2004-509821).

References (43)

  • K. Fent et al.

    Aquat. Toxicol.

    (2006)
  • C. Carlsson et al.

    Sci. Total Environ.

    (2006)
  • S.D. Costanzo et al.

    Mar. Pollut. Bull.

    (2005)
  • J.B. Ellis

    Environ. Pollut.

    (2006)
  • T.A. Ternes

    Trends Anal. Chem.

    (2001)
  • D. Bendz et al.

    J. Hazard. Mater.

    (2005)
  • D.W. Kolpin et al.

    Sci. Total Environ.

    (2004)
  • N. Lindqvist et al.

    Water Res.

    (2005)
  • D. Ashton et al.

    Sci. Total Environ.

    (2004)
  • P. Roberts et al.

    Sci. Total Environ.

    (2006)
  • S.S. Verenitch et al.

    J. Chromatogr. A

    (2006)
  • Z. Moldovan

    Chemosphere

    (2006)
  • D.A. Lambropoulou et al.

    J. Chromatogr. A

    (2002)
  • D.L. Giokas et al.

    J. Chromatogr. A

    (2004)
  • T. Poiger et al.

    Chemosphere

    (2004)
  • H.-B. Lee et al.

    J. Chromatogr. A

    (2005)
  • J.L. Santos et al.

    Anal. Chim. Acta

    (2005)
  • J.L. Santos et al.

    Environ. Int.

    (2007)
  • R. Hirsch et al.

    Sci. Total Environ.

    (1999)
  • J.D. Cahill et al.

    J. Chromatogr. A

    (2004)
  • S. Castiglioni et al.

    J. Chromatogr. A

    (2005)
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