炽灼残渣操作指南
Operation Guidelines for the Determination of Residue on Ignition
1. 目的 PURPOSE
1.1. 本规程旨在指导炽灼残渣操作。
The operation guidelines are intended to guide the operation of residue on ignition (ROI) experiment.
2. 范围 SCOPE
2.1. 本规程适用于检查有机药物中混入的非挥发性无机杂质。
The guidelines apply to all ROI analysis conducted at Analytical Department.
3. 责任 RESPONSIBILITY
3.1. 分析部负责执行本规程。
Analytical staff: follow the procedures defined in the guidelines
Management: ensures that the guidelines are followed
4. 规程PROCEDURE
4.1. 参照USP34<281> Residue on Ignition
Reference: USP34<281> Residue on Ignition
4.1.1. 取干净、合适材质的坩埚（如二氧化硅、铂金、石英或者瓷质）置马弗炉内，经640 ℃炽灼（一般炽灼过夜）；取出坩埚置于干燥器（硅胶或其他合适干燥剂）中冷却约1.5小时；精密称定坩埚的重量W1。
Ignite a suitable crucible (for example, silica, platinum, quartz, or porcelain) at 640 ℃ (typically overnight) in a muffle furnace, cool for about 1.5 hours in a desiccator (silica gel or other suitable desiccant), weigh it accurately as W1.
注：如供试品分子中含有碱金属或氟元素，则应使用铂坩埚，含磷或含硅化合物建议采用其
他方法。
Note: A platinum crucible should be used for testing of alkali metals or fluorine substances. Determination of ROI of phosphorus or silicon compounds should be advised to use other methods.   
4.1.2. 精密称取1.0~2.0 g样品W2，或个别文献特定说明质量的样品，放在之前冷却后的坩埚中。
Weigh accurately 1.0 to 2.0 g of the substance as W2, or the amount specified in the individual monograph, in the crucible.
注：在称取样品时，应将样品置于称量纸上称量；如果样品引湿性较强，应以初次稳定的读数为准。
Note: weigh the substance on the weight paper, which is hygroscopic, should register the initial, steady value.
4.1.3. 用少量（通常1mL）硫酸润湿样品，然后在尽量低的温度下慢慢加热(加热样品至有微量烟冒出，恒定温度直至不冒烟, 随后，逐渐旋至高档位，缓慢加热至不再有白烟生成；避免供试品受热骤然膨胀或燃烧而溢出)，直至样品完全炭化；冷却；然后, 除了个别文献另有说明外，再加入少量（通常1mL）硫酸润湿样品，缓慢加热至不再有白烟生成。
Moisten the sample with a small amount (usually 1mL) of sulfuric acid, then heat gently at a temperature as low as practicable(adjust electric cooker knob to heat gently until smoke generated slightly, keep the temperature constant until there is no smoke. Then adjust electric cooker knob to high temperature gently until white fumes are no longer evolved; avoid the sample overflow because of expanding suddenly or burning.) until the sample is thoroughly charred, cool, then, unless otherwise directed in the individual monograph, moisten the residue with a small amount (usually 1mL) of sulfuric acid, heat gently until white fumes are no longer evolved.
4.1.4. 将上述坩埚置马弗炉内，坩埚盖斜盖于坩埚上，除非个别文献另有说明，在640 ℃炽灼(一般炽灼过夜)，直至样品完全灰化；取出坩埚置于干燥器（硅胶或其他合适干燥剂）中冷却约1.5小时；精密称定坩埚及残渣的重量W3。
Ignite the sample at 640 ℃（typically overnight）and the crucible may be loosely covered with a suitable lid during the igniting， unless another temperature is specified in the individual monograph, until the residue is completely incinerated, cool the crucible for about 1.5 hours in a desiccator (silica gel or other suitable desiccant), weigh it accurately as W3.
4.1.5. 按公式计算其炽灼残渣：ROI% = (W3-W1)/W2*100。
weigh weight 区别Calculate the percentage of residue as follows: ROI% = (W3-W1)/W2*100.
4.1.6. 如果算得的数值明显超过特定文献的限度，则需重复以上硫酸润湿、加热、炽灼的过程，直至连续两次测得的残渣的质量相差小于0.5 mg，或者算得的炽灼残渣在特定的文献限度内。
If the amount of the residue so obtained exceeds the limit specified in the individual monograph, repeat the moistening with sulfuric acid, heating and igniting as before, until two consecutive weightings of the residue do not differ by more than 0.5 mg or until the percentage of residue complies with the limit in the individual monograph.
   
4.2. 参照Ch.P 2010 ⅧN 炽灼残渣检查法
Reference: Ch.P 2010 ⅧN Residue on Ignition
4.2.1 取干净的坩埚（如供试品分子中含有碱金属或氟元素，则应使用铂坩埚）置马弗炉内，将坩埚盖斜盖于坩埚上，经700℃炽灼(一般炽灼过夜)；取出坩埚置于干燥器（硅胶或其他合适干燥剂）中，盖好坩埚盖，放冷至室温（约1.5h）；精密称定坩埚(去盖)的重量。再以同样条件重复操作，直至恒重W1 (连续两次质量相差小于0.3 mg)，备用。炽灼至恒重的第二次称重应在继续炽灼30 min后进行。
Ignite a suitable crucible (a platinum crucible should be used for testing of alkali metals or fluorine substances) at 700℃in a muffle furnace （typically overnight）and the crucible may be loosely covered with a suitable lid during the igniting, cool the crucible covered with the lid in a desiccators (silica gel or other suitable desiccant) about 1.5 hours, weigh the crucible (without lid) accurately. Repeat the procedure, until the crucible reach the constant
weight W1 （two consecutive weightings of the crucible do not differ by more than 0.3 mg）. The second weighing after reach the constant weight should be conducted in 30 minutes of continuous ignition.
注：含磷或含硅化合物建议采用其他方法。
Note: Determination of ROI of phosphorus or silicon compounds should be advised to use other methods.
4.2.2 取供试品1.0~2.0 g或各品种项下规定的重量，置已炽灼至恒重的坩埚内，精密称定其重量为W2。
Weigh accurately 1.0 to 2.0 g of the substance as W2, or the amount specified in the individual monograph, in the crucible.
4.2.3 将盛有供试品的坩埚置电炉上缓缓灼烧（应避免供试品受热骤然膨胀或燃烧而溢出），直至供试品全部炭化，并不再冒烟；放冷至室温；除另有规定外，滴加硫酸0.5~1.0 mL，使其全部润湿，浸润约10分钟后继续在电炉上缓慢加热至硫酸蒸气除尽。
Heat the crucible with the sample gently at a temperature as low as practicable (avoid the sample overflow because of expanding suddenly or burning) until the sample is thoroughly charred and white fumes are no longer evolved, cool, then, unless otherwise directed in the individual monograph, moisten the residue with 0.5~1.0 mL sulfuric acid for about 10 min, then heat gently until fumes are no longer evolved.