下一步，20片药片称重并磨粉。取100mg的动力重量放入100ml烧瓶中，加入15ml甲醇。之后，加入85毫升的水，使体积调整到100毫升。然后，取1毫升溶液，放入100毫升的容量闪光灯中。实验采用紫外可见双光束分光光度计，配以长度为1 cm的石英细胞。选择合适的波长在很大程度上取决于样品的性质和溶解度。为了开发一种坚固和合适的方法，重要的是在测试了稀释剂、缓冲液、缓冲液浓度和色谱条件等不同参数后选择分析条件(Brown et al.， 2009)。当使用甲醇-水稀释剂时，得到了最佳的效果，并将其脱气入超声波浴。定量分析可以通过准确度测试来确定。这是在标准加法方法的帮助下完成的，该方法在三个不同的级别上实现。标准数量应在50%左右。样品中应添加100%和125%。
这一结果还表明，在每一种添加的浓缩物中都能得到最佳的加药回收率。这决定了方法的准确性。利用线性度进一步验证了定量分析的正确性。对乙酰氨基酚的浓度范围在0- 150ppm之间。实验发现该药物的反应完全线性，线性回归方程为y = 0.004x+0.007，相关系数为0.998。当设备设计中出现故障时，就会对物质吸收光谱测量的准确性产生影响。这是因为杂散光会在线性范围内减少(Forster, 2004)。这将导致被测物质的吸收率降低。另一个缺点是使用了电路设计和检测器电路质量，这将对测量信号时观察到的噪声量产生影响。这将导致仪器灵敏度的降低。这种方法非常复杂，需要大量的专业知识才能成功地完成它。实验中使用的样品容易燃烧和降解。
In the next step, 20 tablets are weighed and powdered. The powered weight of 100 mg is taken into an 100 ml flask and 15 ml of methanol is added. After this, 85 ml of water is added in order to adjust the volume to 100 ml. Following this, 1 ml of solution is withdrawn and is taken to the 100 ml volumetric flash. In order to do the experiment, UV Visible double beam spectrophotometer is used along with the matched quartz cells of 1 cm length.The selection of the proper wavelength is largely dependent on the nature of the sample and the solubility of the same. For the purpose of developing a rugged and a suitable method it is important to select a analytic condition after testing of the different parameters such as diluents, buffer, concentration of the buffer and the chromatographic conditions (Brown et al., 2009). When the diluents of methanol-water are used, the best results have been obtained and are degassed into an ultrasonic bath. Quantitative analysis can be confirmed with the help of the accuracy test. This is done with the help of the standard addition method which is implemented at three different levels. Standard quantity equivalent should be around 50 %. 100 % and 125 % should be added to the sample.
This result also states that the best recoveries of the spiked drugs can be obtained at each and every added concentrate. This determines the accuracy of the method. Quantitative analysis can be further validated with the help of linearity. The concentration range used is between 0-150 ppm for paracetamol. From the experiment, the response of the drug had been found to be completely linear and the linear regression equation was y = 0.004x+0.007 with the value of correlation coefficient as 0.998.Whenever there is a fault in the design of the equipment, there can be an impact on the accuracy of the spectra measurement of absorption of the substance. This is because there will be a decrease in the stray light by a linear range (Förster, 2004). This would lead to the reduction in the absorbency of the substance which is to be measured. Another disadvantage is the use of the electric circuit design and the detector circuit quality which would have an impact on the amount of noise that would be observed in the measurement of the signal. This will lead to the reduction of the sensitivity of the instrument. This method is sophisticated and it requires a lot of expertise in order to complete it in a successful manner. The samples used in the experiment are prone to burning and degradation.