Department of Chemistry and Physics, Nova Southeastern University, Fort Lauderdale, FL 33314, USA.
Phys Chem Chem Phys. 2021 Jan 21;23(2):1221-1233. doi: 10.1039/d0cp05543c.
Interactions of the analgesic medications dextropropoxyphene (DPP, opioid), paracetamol (PCL, nonnarcotic), tramadol (TDL, nonnarcotic), ibuprofen (IBN, nonsteroidal anti-inflammatory drug (NSAID)), and naproxen (NPX, NSAID) with pristine graphene (GN) and nitrogen-doped GN (NGN; containing only graphitic N atoms) nanosheets were explored using density functional theory (DFT) in the gas and aqueous phases. Calculations in the aqueous phase were performed using the integral equation formalism polarized continuum model (IEFPCM). Calculated geometry-optimized structures, partial atomic charges (determined using Natural Bond Orbital analysis), highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gaps, work functions (determined using time-dependent DFT), and molecular electrostatic potential plots showed that the adsorption process is physical in nature (viz. physisorption), primarily due to noncovalent π-π and van der Waals interactions. In addition, calculated adsorption energies (ΔEad) were exergonic, indicating that formation of the analgesic/GN and analgesic/NGN complexes is thermodynamically favorable in the gas (ΔEad values for analgesic/GN and analgesic/NGN were in the range of -66.56 kJ mol-1 to -106.78 kJ mol-1) and aqueous phases (ΔEad values for analgesic/GN and analgesic/NGN complexes were in the range of -58.75 kJ mol-1 to -100.46 kJ mol-1). Generally, for GN and NGN, adsorption was more endergonic in the aqueous phase by as much as +10.41 kJ mol-1. Calculated solvation energies (ΔEsolvation) were exergonic for all analgesic/GN complexes (ΔEsolvation values were in the range of -56.50 kJ mol-1 to -66.17 kJ mol-1) and analgesic/NGN complexes (ΔEsolvation values were in the range of -77.26 kJ mol-1 to -87.96 kJ mol-1), with analgesic/NGN complexes exhibiting greater stability in aqueous solutions (∼20 kJ mol-1 more stable). In summary, the results of this theoretical study demonstrate that the adsorption and solvation of analgesics on GN and NGN nanosheets is thermodynamically favorable. In addition, generally, analgesic/NGN complexes exhibit higher adsorption affinities and solvation energies in the gas and aqueous phases. Therefore, GN and NGN nanosheets are potential adsorbents for extracting analgesic contaminants from aqueous environments such as aquatic ecosystems.
使用密度泛函理论（DFT）在气相和水相条件下研究了镇痛药右丙氧芬（DPP，阿片类）、对乙酰氨基酚（PCL，非麻醉性）、曲马多（TDL，非麻醉性）、布洛芬（IBN，非甾体抗炎药（NSAID））和萘普生（NPX，NSAID）与原始石墨烯（GN）和氮掺杂石墨烯（NGN；仅含石墨 N 原子）纳米片之间的相互作用。水相中的计算使用积分方程形式极化连续模型（IEFPCM）进行。计算的几何优化结构、部分原子电荷（使用自然键轨道分析确定）、最高占据分子轨道（HOMO）-最低未占据分子轨道（LUMO）能隙、功函数（使用时间相关 DFT 确定）和分子静电势图表明，吸附过程本质上是物理的（即物理吸附），主要是由于非共价的π-π 和范德华相互作用。此外，计算的吸附能（ΔEad）为放热能，表明在气相（镇痛药/GN 和镇痛药/NGN 的 ΔEad 值在-66.56 kJ mol-1 到-106.78 kJ mol-1 范围内）和水相（镇痛药/GN 和镇痛药/NGN 复合物的 ΔEad 值在-58.75 kJ mol-1 到-100.46 kJ mol-1 范围内）中形成镇痛药/GN 和镇痛药/NGN 复合物是热力学有利的。一般来说，对于 GN 和 NGN，在水相中的吸附能最多高出 10.41 kJ mol-1。所有镇痛药/GN 复合物的溶剂化能（ΔEsolvation）均为放热能（ΔEsolvation 值在-56.50 kJ mol-1 到-66.17 kJ mol-1 范围内）和镇痛药/NGN 复合物（ΔEsolvation 值在-77.26 kJ mol-1 到-87.96 kJ mol-1 范围内），镇痛药/NGN 复合物在水溶液中更稳定（稳定约 20 kJ mol-1）。总之，这项理论研究的结果表明，镇痛药在 GN 和 NGN 纳米片上的吸附和溶剂化在热力学上是有利的。此外，一般来说，镇痛药/NGN 复合物在气相和水相中的吸附亲和力和溶剂化能更高。因此，GN 和 NGN 纳米片是从水生生态系统等水环境中提取镇痛药污染物的潜在吸附剂。
