Efficient absorbance detection of a low-volume chromatography peak is a difficult task. In this work, an improved design of the fused silica capillary flow cell for absorbance detection in microcolumn liquid chromatography is described. The cell was fabricated from 0.15 mm I. D. fused silica capillary and silica optical fibres. Optical fibres were fully integrated into the cell design and enabled a convenient and effective connection of the cell with the light source and light detector (265 nm UV LED and photodiode in this work). Manufactured cells covered the range of physical lengths 3.1–9.9 mm (55–175 nL) and were used without any focusing optics and slits. Baseline noise was typically below 0.05 mAU and the effective optical path determined in the experiments was 83–97% of the cell's physical length. The level of stray (parasitic) light indicated by a 1% deviation from linearity at 1.7 AU was 0.08% only. The proposed cell design was found to be moderately susceptible to the refractive index change (20–35 mAU baseline change in 5–95% (v/v) gradient of acetonitrile or methanol in a mixture with water, G index up to 4 AU·s/RIU). Manufactured cells were finally applied for absorbance detection of components of test the mixture eluted off 0.3 mm I. D. microcolumn. 9.9 mm cell (175 nL) with an effective optical path of 8.9 mm exhibited contribution to the broadening of chromatography peak comparable with commercial 6 mm (80 nL) rectangular flow cell.

低体积色谱峰的有效吸光度检测是一项艰巨的任务。在这项工作中，描述了用于微柱液相色谱中吸光度检测的熔融石英毛细管流通池的改进设计。该电池由 0.15 毫米内径的熔融石英毛细管和石英光纤制成。光纤完全集成到电池设计中，使电池与光源和光检测器（本工作中的 265 nm UV LED 和光电二极管）能够方便有效地连接。制造的电池覆盖了 3.1-9.9 毫米（55-175 nL）的物理长度范围，并且在没有任何聚焦光学器件和狭缝的情况下使用。基线噪声通常低于 0.05 mAU，实验中确定的有效光程为电池物理长度的 83–97%。1.7 AU 处的线性偏差 1% 表明的杂散（寄生）光水平仅为 0.08%。发现拟议的电池设计对折射率变化有一定的敏感性（乙腈或甲醇与水的混合物中 5–95% (v/v) 梯度的 20–35 mAU 基线变化，G 指数高达 4 AU· s/RIU）。制造的细胞最终用于测试组分的吸光度检测，混合物从0.3mm ID微柱上洗脱。有效光程为 8.9 mm 的 9.9 mm 流通池 (175 nL) 表现出与商用 6 mm (80 nL) 矩形流通池相媲美的色谱峰展宽贡献。发现拟议的电池设计对折射率变化有一定的敏感性（乙腈或甲醇与水的混合物中 5–95% (v/v) 梯度的 20–35 mAU 基线变化，G 指数高达 4 AU· s/RIU）。制造的细胞最终用于测试组分的吸光度检测，混合物从0.3mm ID微柱上洗脱。有效光程为 8.9 mm 的 9.9 mm 流通池 (175 nL) 表现出与商用 6 mm (80 nL) 矩形流通池相媲美的色谱峰展宽贡献。发现所提出的电池设计对折射率变化适度敏感（乙腈或甲醇与水的混合物中 5–95% (v/v) 梯度的 20–35 mAU 基线变化，G 指数高达 4 AU· s/RIU）。制造的细胞最终用于测试组分的吸光度检测，混合物从0.3mm ID微柱上洗脱。有效光程为 8.9 mm 的 9.9 mm 流通池 (175 nL) 表现出与商用 6 mm (80 nL) 矩形流通池相媲美的色谱峰展宽贡献。