Yaul Mayur, Bhatti Raj, Lawrence Stephen
Medway School of Engineering, University of Greenwich, Kent ME4 4TB, UK.
Biomed Microdevices. 2008 Feb;10(1):123-8. doi: 10.1007/s10544-007-9117-8.
In this paper we investigate a number of gas flames for fire polishing borosilicate glass capillaries used in the manufacturing of IVF micro-pipettes. Hydrofluoric acid (HF) was also used as an alternative to finish the pipette end. Glass micro tools in the IVF industry are drawn from hollow glass capillaries of diameter 1 mm. These capillaries are cut manually to a length of 100 mm from hollow glass rods resulting in sharp and chipped edges. These capillaries are held in a customised holder having padding of soft silicone or rubber. Sharp and uneven edges of these capillaries pick up particles of rubber or soft silicone shavings, rendering them ineffective for IVF treatments. The working range of borosilicate glass is 800-1,200 degrees C. The experiments involved analysis of fire polishing process for borosilicate glass capillaries using candle, butane, propane, 2350 butane propane, oxyacetylene gas flames, finding the optimum distance of the capillary relative to the flame, optimum time for which the capillary should be held in the flame and optimum region of the flame which gives the required temperature range. The results show that 2350 butane propane gas mix is optimum for fire polishing of borosilicate glass capillaries. The paper is concluded by comparing the results of fire polishing with the results of acid polishing, in which HF of 1.6% concentration is used to etch the ends of the borosilicate glass pipettes.
在本文中，我们研究了多种用于对体外受精（IVF）微量移液器制造中使用的硼硅酸盐玻璃毛细管进行火焰抛光的气体火焰。氢氟酸（HF）也被用作完成移液器末端处理的替代方法。IVF行业中的玻璃微工具由直径1毫米的中空玻璃毛细管拉制而成。这些毛细管从空心玻璃棒上手动切割成100毫米的长度，导致边缘锋利且有缺口。这些毛细管被放置在一个带有软硅胶或橡胶衬垫的定制夹具中。这些毛细管锋利且参差不齐的边缘会沾上橡胶或软硅胶碎屑颗粒，使其在IVF治疗中无法使用。硼硅酸盐玻璃的工作温度范围是800 - 1200摄氏度。实验涉及使用蜡烛、丁烷、丙烷、2350丁烷丙烷、氧乙炔气体火焰对硼硅酸盐玻璃毛细管的火焰抛光过程进行分析，找出毛细管相对于火焰的最佳距离、毛细管应在火焰中保持的最佳时间以及能提供所需温度范围的火焰最佳区域。结果表明，2350丁烷丙烷气体混合物对于硼硅酸盐玻璃毛细管的火焰抛光是最佳的。本文通过将火焰抛光的结果与酸抛光的结果进行比较来得出结论，在酸抛光中使用浓度为1.6%的HF蚀刻硼硅酸盐玻璃移液器的末端。
