Application Of Inductively Coupled Plasma Mass Spectrometry And Graphite Furnace Atomic Absorption Techniques In Drug Quality Evaluation

Inorganic element analysis is one of the important contents of drug quality evaluation.Inductively coupled plasma mass spectrometry(ICP-MS)and graphite furnace atomic absorption spectrometry(GFAAS)are two commonly used elemental analysis techniques,which are widely used in quality evaluation of traditional Chinese medicine and raw materials.In the present study,ICP-MS was used to analyze a variety of elements in the four medicinal parts of Poria cocos(Schw.)Wolf and ICP-MS and GFAAS were used to determine the residual palladium in terbutaline sulfate.Poria is the dry sclerotia of Poria cocos(Schw.)Wolf of fungus of a branch of multiaperture mushroom.Different medicinal parts have different functions and they are Poria cum Radix Pini,White Poria,Rubra Poria and Poriae Cutis.Up to date,there have been many studies on organic components and their pharmacological effects in Poria cocos(Schw.)Wolf.The researches on inorganic elements are limited to some elements in one or two kinds of medicinal parts.There were no studies on comparing a variety of elements in the four medicinal parts.In this study,an ICP-MS method were developed to firstly quantify 26 kinds of beneficial or harmful elements and then was used to compare different medicinal parts of Poria cocos(Schw.)Wolf,which provided a reference for the safe control of harmful heavy metals and the pharmacological effects of beneficial elements.Terbutaline sulfate is a β2 adrenergic receptor agonists.During its synthesis process,Palladium is often used as a catalyst.Excessive residual palladium metal can cause damage to the health.Therefore,it is necessary to strictly control the residual amount of palladium in raw materials.But there is no report on the determination of residual palladium in terbutaline sulfate.Inthis study,two methods,GFAAS and ICP-MS,were established for the determination of residual palladium in terbutaline sulfate,and the differences between the two methods were compared and the results of six batches of samples were analyzed by t test,which provided the basis for the quality control of terbutaline sulfate.Part one Application of ICP-MS in quality evaluation of differentmedicinal parts of Poria cocos(Schw.)WolfObjective: To establish an ICP-MS method for the simultaneous quantitation of 26 elements in Poria cocos(Schw.)Wolf and compare differences of elements in four medicinal parts including Poria cum Radix Pini,White Poria,Rubra Poria and Poriae Cutis.Methods:1 Preparation of sample solutions: Poria cum Radix Pini,White Poria,Rubra Poria and Poriae Cutis medicine were crushed.The powder(0.1 g,100mesh)was accurately weighed into a digestion tank,and then 6 m L nitric acid was added.The sample was set on the temperature control heating plate to pre-digestion,130℃ for 30 min,and then taken out.The lid was covered on digestion tank after the sample was coolled to room temperature.Microwave digestion program was set: from room temperature raised to 130℃ in 10 min,hold 5 min.And then raised from 130℃ to 170℃ in 5 min,hold 25 min.After completion of the digestion,set the temperature of the heating plate at130℃ to remove nitric acid until the solution volume was about 0.5 m L.The solution was transferred to the 25 m L volumetric flask,diluted with 2% nitric acid.2 Determination conditions:Simultaneous determination of 26 inorganic elements in different parts of Poria cocos(Schw.)Wolf by ICP-MS,including harmful elements(Cu,Pb,Cd,As,Hg and so on)and beneficial elements(Mn,Zn,Ca and so on).ICP-MS parameters RF power: 1500 W,reflected power: 2W,data acquisition: jump peak,calibration method: internal standard method,plasma flow rate: 15 L/min,carrier gas flow rate: 1.1 L/min,spray chamber temperature: 2℃,pump speed: 0.3 r/min.3 Method validation: In this study,the method validation was carried out on linearity,limit of detection,limit of quantification,instrument precision,repeatability,recovery and stability.4 Assay and classification of 26 elements:By drawing the line chart of 26 elements of the content,we could intuitively compare the content of the elements in samples.SPSS 13.0software was used to classify and compare the samples by hierarchical cluster analysis,principal component analysis,one-way ANOVA,K-independent samples nonparametric tests and relative standard deviation.The similarities and differences between different medicinal parts and between the same drug samples were analyzed.Results:The results showed that the linearity and concentration of 26 chemical elements were good in the range of the measured concentration,and the correlation coefficients were all more than 0.9927.The instrument precision RSD was less than 5%.The repeatability RSD of 26 chemical elements in Poria cum Radix Pini,White Poria,Rubra Poria and Poriae Cutis were less than 6.4%,5.8%,5.6% and 5.4%,respectively,and the recoveries range were94.0~115.4%,98.8~115.9%,99.2~114.0%,97.0~112.8%.The sample solutions were stable at room temperature for 24 h.In this study,the contents of 26 kinds of inorganic elements in four medicinal parts of Poria were quantified for the first time,and the method validation results were good.The line graph showed that most of the elements contents in Poriae Cutis were higher than those of other parts.Harmful elements,such as copper,lead,cadmium,arsenic,mercury,in 31 batches of samples,did not exceed the limit in Chinese Pharmacopoeia 2015 edition.The contents of Na,Mg,Al,P,K,Ca and Fe in the four medicinal parts were higher than that of the other elements,while the contents in Poriae Cutis were the highest and the contents of White Poria were relatively low.By the hierarchical cluster analysis method,four medicinal parts can be divided into two classes,class A included Poria cum Radix Pini,White Poria,Rubra Poria,and class B was Poriae Cutis.Two classes were significantly different,but the differences between the three parts of class A were small.The results obtained by principal component analysis was consistent with those obtained by hierarchical cluster analysis.SPSS software was used to conduct the one-way ANOVA and K-independent samples nonparametric tests.The results showed that: 1)there had no difference in the content of Sn(p=0.941),while the others were different(p were all lower than 0.05);2)Poria cum Radix Pini and White Poria were different in the elements Na,Cu,Sb,V 3)Poria cum Radix Pini and Rubra Poria had no difference in the elements of Na,P,Cr,Ni,Cu,Zn,Pb,Mo,Sb.4)Poria cum Radix Pini and Poriae Cutis had no difference in the elements of Na,Hg.5)White Poria and Rubra Poria had no difference in the elements of P,Ca,Cr,Ni,Zn,Sr,Pb,Mo,Sb.6)White Poria and White Poria had no difference in the elements of Sb,Hg.7)Rubra Poria and Poriae Cutis had no difference in the elements of Na,Sb,As 8)Four parts of the V content were different from each other,Poriae Cutis > Rubra Poria> Poria cum Radix Pini> White Poria.The results of relative standard deviation analysis showed that: 1)The similar elements in Poria cum Radix Pini were Na,Mg,Ca,Cr,Co,Ni,Zn,Sr,Mo,Sn and Sb.2)The similar elements in White Poria were Na,Mg,P,K,Ca,Cr,Co,Ni,Cu,Zn,Sr,Mo,Sb.3)The similar elements in the Rubra Poria were Na,Mg,Ca,Cr,Co,Ni,Zn,Sr,Mo.4)The different elements in Poriae Cutis were Cu,Zn,Sn,Sb,Hg,Ba.Conclusions: For the first time we established a method for simultaneous determination of 26 beneficial or harmful elements in Poria cum Radix Pini,White Poria,Rubra Poria,Poriae Cutis by ICP-MS after microwave digestion.The method has high sensitivity and low detection limit,wide linear range.It could be developed to rapidly detect a variety of elements in quantities of samples.Poria cocos(Schw.)Wolf different medicinal parts and the different samples from the same medicinal parts were different;the harmful elements of commercially available four medical parts of Poria cocos(Schw.)Wolf meetthe requirements.Part two Determination of residual palladium in terbutaline sulfate byICP-MS and GFAASObjective: To establish two methods for the determination of trace palladium in terbutaline sulfate by GFAAS and ICP-MS,and make comparation between between two methods.Methods:1 Preparation of sample solutions:Sample solutions were prepared by wet digestion by GFAAS.The powder(about 0.1 g)was accurately weighed into a beaker,and then 6 m L nitric acid was added.The beaker was covered a surface dish to digest until there was no longer yellow smoke.And then remove the surface dish,continue to heat the solution near dry,cool to room temperature.2% nitric acid was added to dissolve the residue.The solution was transferred to the 5 m L volumetric flask,diluted with 2% nitric acid.Sample solutions were prepared by microwave digestion by ICP-MS.The powder(about 0.1 g)was accurately weighed into a digestion tank,and then 6m L nitric acid was added.The sample was set on the temperature control heating plate to pre-digestion,130℃ for 30 min,and then taken out.The lid was covered on digestion tank after the sample was coolled to room temperature.Microwave digestion program was set: from room temperature raised to 130℃ in 10 min,hold 5 min.And then raised from 130℃ to 170℃in 5 min,hold 25 min.After completion of the digestion,set the temperature of the heating plate at 130℃ to remove nitric acid until the solution volume was about 0.5 m L.The solution was transferred to the 5 m L volumetric flask,diluted with 2% nitric acid.2 Determination conditions:GFAAS: Operating conditions light source: palladium hollow cathode lamp,wavelength: 247.6 nm,lamp current: 7.0 m A,slit width: 0.4 nm,injection volume: 20 μL,background correction: Zeeman effect,instantaneous signal type: peak height.Graphite furnace heating process: two-step dryingmethod,90℃-90℃,slope 10 s,hold 10 s.90℃-120℃,slope 20 s,hold 15 s.Ashing,900℃-900℃,slope 10 s,hold 0 s.Atomization,2300℃-2300℃,slope 0 s,hold 5 s.Cleaning,2500℃-2500℃,slope 0 s,hold 4 s.Cooling,0℃to 0℃,slope 0 s,hold 10 s.ICP-MS: 115 In was as the internal standard element.ICP-MS parameters RF power: 1500 W,reflected power: 2 W,data acquisition: jump peak,calibration method: internal standard method,plasma flow rate: 15 L/min,carrier gas flow rate: 1.1 L/min,spray chamber temperature: 2℃,pump speed:0.3 r/min.3 Method validation: The method validation was carried out on specificity,linearity,limit of detection,limit of quantification,instrument precision,repeatability,recovery and stability.4 Assay results: Six batches of samples were determined and compared.Wet digestion-GFAAS and microwave digestion-ICP-MS method were established for the determination of trace platinum in terbutaline.Independent samples t test were applied to analyze results.Results : The specificity of GFAAS and ICP-MS were good.The detection limits were 0.29 μg/L,0.03 μg/L respectively and linear relationship were good,r were 0.9996,0.9987.The RSD of instrument precision were6.9%,5.3% and the average recovery were 103.5%,101.2%,RSD were 7.6%,2.6%.The RSD of the solution stability was 5.1% and 6.5%,respectively.Both methods could meet the requirements of quality control.The results of samples by the two methods were less than 1 ppm,which was in accordance with the EMEA limit.The p value were larger than 0.05 by two independent samples t test.The results showed that there was no statistical difference between the two methods.Conclusions:Both methods could be used for determination of residual palladium in terbutaline sulfate.Compared with the GFAAS method,ICP-MS method has lower detection limit,better reproducibility,wider linear range,and suitable for the rapid determination of large quantities of samples.ICP-MS is worth promoting.