A simple, cost-effective analysis combining solventless extraction, thermal desorption, and determination of volatile organic compounds (VOCs) was developed and validated. A needle trap device (NTD) packed with the sorbent Carboxen1000 was used as a time-weighted average (TWA) diffusive sampler to collect target compounds by molecular diffusion and adsorption to the packed sorbent. This process can be described with derivations of Fick's first law of diffusion, which expresses the relation between the TWA concentrations to which the passive sampler is exposed and the mass of analytes adsorbed to the packed sorbent in the sampler. The effects of experimental factors such as temperature, pressure, humidity, and face velocity were taken into account in applying diffusive sampling under nonideal conditions. This study demonstrates that NTD is effective for air analysis of benzene, toluene, ethylbenzene, and o-xylene (BTEX), due to the good adsorption/desorption quality of Carboxen 1000 and to the special geometric shape of the needle with a small cross section avoiding the need for calibration. Storage tests showed good storage stability for BTEX. Verification of the theoretical model showed good agreement between theoretical and experimental sampling rates. Method validation done against NIOSH method 1501, SPME, and NTD active sampling revealed good agreement between those methods. Automated NTD sample introduction to a gas chromatograph facilitates the use of this technology for industrial hygiene applications.

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Gastric cancer (GC) is the 3rd leading cause of tumor‑associated mortality worldwide. The efficacy of paclitaxel, a frequently used GC chemotherapeutic agent, is hindered due to drug resistance, dose‑induced toxicity and adverse side effects. Silibinin, an active compound of a widely consumed dietary supplement, milk thistle extract, has recently been demonstrated to have strong antitumor efficacy in a human GC cell model. Thus, to enhance the efficacy of GC treatment, the present study evaluated whether silibinin exerted a synergistic therapeutic effect with paclitaxel. It was observed that the combination of silibinin‑paclitaxel was able to trigger cell cycle arrest and apoptosis. The cell cycle arrest assay indicated that silibinin and paclitaxel alone induced a G2/M phase arrest, and the silibinin‑paclitaxel combination strongly inhibited G2/M cells from entering the S phase. The apoptosis assay and western blot analysis of poly‑ADP‑ribose polymerase, pro‑caspase 3 and pro‑caspase 8 demonstrated that silibinin synergized with paclitaxel in promoting SGC‑7901 GC cell apoptosis. Furthermore, upregulation of the ratio of apoptosis regulator Bcl‑2/apoptosis regulator BAX and tumor necrosis factor receptor superfamily member 6 (Fas)/Fas ligand indicated that the silibinin‑paclitaxel combination activated the death receptor‑mediated pathway in SGC‑7901 cells. The results of the present study suggested that silibinin enhanced the therapeutic potential of paclitaxel against human GC SGC‑7901 cells.