Determination of Parabens in Pharmaceutical Formulations by Solid-Phase Microextraction-Ion Mobility Spectrometry

Abstract

Solid-phase microextraction (SPME) coupled with ion mobility spectrometry (IMS) was used for the detection and quantitation of 4-hydroxybenzoate preservatives, methylparaben, ethylparaben, propylparaben, and butylparaben, in commercial pharmaceutical products. For the first time, SPME-IMS is described for the simultaneous detection, separation, and quantitation of multiple analytes in complex matrixes. The parabens are extracted from the samples using SPME, and the analytes on the fiber are heated by the IMS desorber unit and vaporized into the drift tube. The four preservatives differing only by a methyl group were separated in less than 18 ms. The analytical procedure was optimized for fiber coating selection, extraction time, sample pH, sample volume, ionic strength, and IMS conditions. Separation characteristics such as resolution, theoretical plates, and drift times of the parabens were also evaluated based on the direct interfacing of SPME to IMS. The conditions were tested using six over-the-counter topical products containing various combinations of preservatives. Analysis of the samples by SPME-IMS using benzyl paraben as an internal standard yields good comparison to an HPLC method, thereby reinforcing the applicability of this technique as a method for routine analysis. Limits of detection were 10 ng/mL for methylparaben and ethylparaben and 5 ng/mL for propylparaben and butylparaben. Good linearity range and reproducibility of less than 8% were obtained.

Gas chromatographic determination of parabens afterin-situderivatization and dispersive liquid-liquid microextraction

“…Since parabens have no perceptible odor or taste and have neutral pH, they are used as preservatives in cosmetics, in personal care products applied on the skin, hair, scalp, lips, mucosae and nails, in pharmaceutical products, and even in foods and beverages [1,2]. Because of the wide use, parabens are continuously released into the environment [3,4].…”

“…Until recently, it was believed that parabens are safe, at the most causing skin irritation and contact dermatitis in the persons with paraben allergies [1]. However, some years ago, it was determined that paraben preservatives are genotoxic [13], estrogenic, affect the human endocrine system, and probably cause breast cancer [2,14] and male reproductive disorders [15].…”

“…In recent years, a preconcentration method using microextraction techniques is gaining interest. Few articles have been reported on paraben preconcentration using solid-phase microextraction [1,20,22] and different liquid-phase microextraction techniques: single-drop microextraction [12,23], hollowfiber liquid-phase microextraction [24], and dispersive liquid-liquid microextraction (DLLME) [11,25].…”

Hollow fibre liquid phase microextraction of parabens

“…Due to their bactericidal and fungicidal properties they are used extensively as preservatives in pharmaceutical preparations, cosmetics and skin care products [1]. For example, in 1984 parabens were used in 13200 different cosmetic formulations.…”

“…It is its simple, solventless and environmentally friendly. Nevertheless, to our knowledge there have been few reports on paraben SPME [1,8,13].…”