Functional near-infrared spectroscopy in non-invasive neuromodulation

Non-invasive cerebral neuromodulation technologies are essential for the reorganization of cerebral neural networks,which have been widely applied in the field of central neurological diseases,such as stroke,Parkinson’s disease,and mental disorders.Although significant advances have been made in neuromodulation technologies,the identification of optimal neurostimulation paramete rs including the co rtical target,duration,and inhibition or excitation pattern is still limited due to the lack of guidance for neural circuits.Moreove r,the neural mechanism unde rlying neuromodulation for improved behavioral performance remains poorly understood.Recently,advancements in neuroimaging have provided insight into neuromodulation techniques.Functional near-infrared spectroscopy,as a novel non-invasive optical brain imaging method,can detect brain activity by measuring cerebral hemodynamics with the advantages of portability,high motion tole rance,and anti-electromagnetic interference.Coupling functional near-infra red spectroscopy with neuromodulation technologies offe rs an opportunity to monitor the cortical response,provide realtime feedbac k,and establish a closed-loop strategy integrating evaluation,feedbac k,and intervention for neurostimulation,which provides a theoretical basis for development of individualized precise neuro rehabilitation.We aimed to summarize the advantages of functional near-infra red spectroscopy and provide an ove rview of the current research on functional near-infrared spectroscopy in transcranial magnetic stimulation,transcranial electrical stimulation,neurofeedback,and braincomputer interfaces.Furthermore,the future perspectives and directions for the application of functional near-infrared spectroscopy in neuromodulation are summarized.In conclusion,functional near-infrared spectroscopy combined with neuromodulation may promote the optimization of central pellral reorganization to achieve better functional recovery form central nervous system diseases.

Exploring non-invasive diagnostics for metabolic dysfunctionassociated fatty liver disease

The population with metabolic dysfunction-associated fatty liver disease(MAFLD)is increasingly common worldwide.Identification of people at risk of progression to advanced stages is necessary to timely offer interventions and appropriate care.Liver biopsy is currently considered the gold standard for the diagnosis and staging of MAFLD,but it has associated risks and limitations.This has spurred the exploration of non-invasive diagnostics for MAFLD,especially for steatohepatitis and fibrosis.These non-invasive approaches mostly include biomarkers and algorithms derived from anthropometric measurements,serum tests,imaging or stool metagenome profiling.However,they still need rigorous and widespread clinical validation for the diagnostic performance.

FibroScan-aspartate transaminase:A superior non-invasive model for diagnosing high-risk metabolic dysfunction-associated steatohepatitis

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)with hepatic histological NAFLD activity score≥4 and fibrosis stage F≥2 is regarded as“at risk”non-alcoholic steatohepatitis(NASH).Based on an international consensus,NAFLD and NASH were renamed as metabolic dysfunction-associated steatotic liver disease(MASLD)and metabolic dysfunction-associated steatohepatitis(MASH),respectively;hence,we introduced the term“high-risk MASH”.Diagnostic values of seven non-invasive models,including FibroScan-aspartate transaminase(FAST),fibrosis-4(FIB-4),aspartate transaminase to platelet ratio index(APRI),etc.for high-risk MASH have rarely been studied and compared in MASLD.AIM To assess the clinical value of seven non-invasive models as alternatives to liver biopsy for diagnosing high-risk MASH.METHODS A retrospective analysis was conducted on 309 patients diagnosed with NAFLD via liver biopsy at Beijing Ditan Hospital,between January 2012 and December 2020.After screening for MASLD and the exclusion criteria,279 patients wereincluded and categorized into high-risk and non-high-risk MASH groups.Utilizing threshold values of each model,sensitivity,specificity,positive predictive value(PPV),and negative predictive values(NPV),were calculated.Receiver operating characteristic curves were constructed to evaluate their diagnostic efficacy based on the area under the curve(AUROC).RESULTS MASLD diagnostic criteria were met by 99.4%patients with NAFLD.The MASLD population was analyzed in two cohorts:Overall population(279 patients)and the subgroup(117 patients)who underwent liver transient elastography(FibroScan).In the overall population,FIB-4 showed better diagnostic efficacy and higher PPV,with sensitivity,specificity,PPV,NPV,and AUROC of 26.9%,95.2%,73.5%,72.2%,and 0.75.APRI,Forns index,and aspartate transaminase to alanine transaminase ratio(ARR)showed moderate diagnostic efficacy,whereas S index and gamma-glutamyl transpeptidase to platelet ratio(GPR)were relatively weaker.In the subgroup,FAST had the highest diagnostic efficacy,its sensitivity,specificity,PPV,NPV,and AUROC were 44.2%,92.3%,82.1%,67.4%,and 0.82.The FIB-4 AUROC was 0.76.S index and GPR exhibited almost no diagnostic value for high-risk MASH.CONCLUSION FAST and FIB-4 could replace liver biopsy as more effectively diagnostic methods for high-risk MASH compared to APRI,Forns index,ARR,S index,and GPR;FAST is superior to FIB-4.

Recent developments in non-invasive methods for assessing metabolic dysfunction-associated fatty liver disease

The prevalence of metabolic dysfunction-associated fatty liver disease(MAFLD)is increasing,affecting over one-third of the global population and contributing to significant morbidity and mortality.Diagnosing MAFLD,especially with advan-ced fibrosis,remains challenging due to the limitations of liver biopsy,the current gold standard.Non-invasive tests are crucial for early detection and management.Among these,the fibrosis-4 index(Fib-4)is widely recommended as a first-line test for screening for liver fibrosis.Advanced imaging techniques,including ultrasound-based elastography and magnetic resonance elastography,offer high accuracy but are limited by cost and availability.Combining biomarkers,such as in the enhanced liver fibrosis score and FibroScan-AST score,enhances diagnostic precision and is recommended to further stratify patients who are considered to be intermediate or high risk from the Fib-4 score.We believe that the future lies in the combined use of biomarkers to improve diagnostic accuracy.

Non-invasively differentiate non-alcoholic steatohepatitis by visualizing hepatic integrinαvβ3 expression with a targeted molecular imaging modality

BACKGROUND Non-invasive methods to diagnose non-alcoholic steatohepatitis(NASH),an inflammatory subtype of non-alcoholic fatty liver disease(NAFLD),are currently unavailable.AIM To develop an integrinαvβ3-targeted molecular imaging modality to differentiate NASH.METHODS Integrinαvβ3 expression was assessed in Human LO2 hepatocytes Scultured with palmitic and oleic acids(FFA).Hepatic integrinαvβ3 expression was analyzed in rabbits fed a high-fat diet(HFD)and in rats fed a high-fat,high-carbohydrate diet(HFCD).After synthesis,cyclic arginine-glycine-aspartic acid peptide(cRGD)was labeled with gadolinium(Gd)and used as a contrast agent in magnetic resonance imaging(MRI)performed on mice fed with HFCD.RESULTS Integrinαvβ3 was markedly expressed on FFA-cultured hepatocytes,unlike the control hepatocytes.Hepatic integrinαvβ3 expression significantly increased in both HFD-fed rabbits and HFCD-fed rats as simple fatty liver(FL)progressed to steatohepatitis.The distribution of integrinαvβ3 in the liver of NASH cases largely overlapped with albumin-positive staining areas.In comparison to mice with simple FL,the relative liver MRI-T1 signal value at 60 minutes post-injection of Gd-labeled cRGD was significantly increased in mice with steatohepatitis(P<0.05),showing a positive correlation with the NAFLD activity score(r=0.945;P<0.01).Hepatic integrinαvβ3 expression was significantly upregulated during NASH development,with hepatocytes being the primary cells expressing integrinαvβ3.CONCLUSION After using Gd-labeled cRGD as a tracer,NASH was successfully distinguished by visualizing hepatic integrinαvβ3 expression with MRI.

Advances in the Research Application of Ultrasound Non-Invasive Stress-Strain Loop Technology in Cardiovascular Diseases

The ultrasound pressure-strain loop (PSL) technique is a non-invasive method of examining myocardial work, which takes into account the effect of cardiac afterload on deformation and combines the overall longitudinal strain force of the left ventricle with the changes in the left ventricular pressure, allowing earlier detection of possible subclinical cardiac damage in patients, and a more accurate and non-invasive assessment of the patient’s myocardial work performance. In this article, we will discuss the progress of PSL applications in cardiovascular diseases.

Ensemble for evaluating diagnostic efficacy of non-invasive indices in predicting liver fibrosis in untreated hepatitis C virus population

BACKGROUND Hepatitis C virus(HCV)infection progresses through various phases,starting with inflammation and ending with hepatocellular carcinoma.There are several invasive and non-invasive methods to diagnose chronic HCV infection.The invasive methods have their benefits but are linked to morbidity and complications.Thus,it is important to analyze the potential of non-invasive methods as an alternative.Shear wave elastography(SWE)is a non-invasive imaging tool widely validated in clinical and research studies as a surrogate marker of liver fibrosis.Liver fibrosis determination by invasive liver biopsy and non-invasive SWE agree closely in clinical studies and therefore both are gold standards.AIM To analyzed the diagnostic efficacy of non-invasive indices[serum fibronectin,aspartate aminotransferase to platelet ratio index(APRI),alanine aminotransferase ratio(AAR),and fibrosis-4(FIB-4)]in relation to SWE.We have used an Artificial Intelligence method to predict the severity of liver fibrosis and uncover the complex relationship between non-invasive indices and fibrosis severity.METHODS We have conducted a hospital-based study considering 100 untreated patients detected as HCV positive using a quantitative Real-Time Polymerase Chain Reaction assay.We performed statistical and probabilistic analyses to determine the relationship between non-invasive indices and the severity of fibrosis.We also used standard diagnostic methods to measure the diagnostic accuracy for all the subjects.RESULTS The results of our study showed that fibronectin is a highly accurate diagnostic tool for predicting fibrosis stages(mild,moderate,and severe).This was based on its sensitivity(100%,92.2%,96.2%),specificity(96%,100%,98.6%),Youden’s index(0.960,0.922,0.948),area under receiver operating characteristic curve(0.999,0.993,0.922),and Likelihood test(LR+>10 and LR-<0.1).Additionally,our Bayesian Network analysis revealed that fibronectin(>200),AAR(>1),APRI(>3),and FIB-4(>4)were all strongly associated with patients who had severe fibrosis,with a 100% probability.CONCLUSION We have found a strong correlation between fibronectin and liver fibrosis progression in HCV patients.Additionally,we observed that the severity of liver fibrosis increases with an increase in the non-invasive indices that we investigated.

A Study on Near-Infrared Non-Invasive Blood Glucose Concentration Regression Prediction Based on PSO-MKL-SVR

To improve the accuracy of predicting non-invasive blood glucose concentration in the near-infrared spectrum, we utilized the Particle Swarm Optimization (PSO) algorithm to optimize hyperparameters for the Multi-Kernel Learning Support Vector Machine (MKL-SVR). With these optimized hyperparameters, we established a non-invasive blood glucose regression model, referred to as the PSO-MKL-SVR model. Subsequently, we conducted a comparative analysis between the PSO-MKL-SVR model and the PSO-SVR model. In a dataset comprising ten volunteers, the PSO-MKL-SVR model exhibited significant precision improvements, including a 16.03% reduction in Mean Square Error and a 0.29% increase in the Squared Correlation Coefficient. Moreover, there was a 0.14% higher probability of the Clark’s Error Grid Analysis falling within Zone A. Additionally, the PSO-MKL-SVR model demonstrated a faster operational speed compared to the PSO-SVR model.

Observation on the Effect of Non-Invasive Ventilator Combined with Conventional Therapy in the Treatment of Chronic Obstructive Pulmonary Disease Complicated with Respiratory Failure

Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:68 patients with COPD combined with respiratory failure treated in our hospital from September 2021 to October 2023 were selected as the research subjects.Using the random number table method,they were divided into a control group and an experimental group of 34 cases each.The control group received conventional symptomatic treatment,and the experimental group received non-invasive ventilator treatment based on the control group.The clinical effects,blood gas indicators(partial pressure of carbon dioxide(PaCO_(2)),partial pressure of oxygen(PaO_(2)),arterial oxygen saturation(SaO_(2))),lung function(forced expiratory volume in 1 second(FEV1),forced vital capacity(FVC),6 min walking distance),complications,and inflammatory factor levels(c-reactive protein(CRP),interleukin-6(IL-6),neutrophil-to-lymphocyte ratio(NLR))of the two groups of patients were observed.Results:(1)The clinical efficacy of the patients in the experimental group(33/97.06%)was more significant as compared with the control group(25/73.53%)(P<0.05);(2)After treatment,the clinical efficacy of the two groups of patients in terms of FEV1,FEV1/FVC,6-minute walking distance,PaO_(2)and SaO_(2)all increased in the experimental group as compared to that of the control group(P<0.05);(3)After treatment,the PaCO_(2),CRP,IL-6,and NLR of the two groups of patients decreased,and the decrease in the experimental group was higher than that of the control group(P<0.05);(4)The patients’complication rate in the experimental group(2/5.88%)was lower as compared to that of the control group(9/26.46%)(P<0.05).Conclusion:Non-invasive ventilators combined with conventional therapy achieved good clinical results in treating patients with COPD and respiratory failure.

Analysis of the Effect of Non-Invasive Positive Pressure Ventilation in Emergency Treatment of Severe Bronchial Asthma with Respiratory Failure

Objective:This study aims to evaluate the clinical efficacy of non-invasive positive pressure ventilation(NIPPV)in patients with severe bronchial asthma combined with respiratory failure.Methods:90 patients with severe bronchial asthma combined with respiratory failure between September 2022 and December 2023 were selected for the study and randomly divided into the experimental group(NIPPV-assisted treatment)and the control group.The differences between the two groups were compared in terms of total effective rate of treatment,days of clinical symptom disappearance,days of hospitalization,lung function indexes,incidence of adverse reactions,and quality of life.Results:Patients in the experimental group had a significantly higher total effective rate of treatment(97.78%)than the control group(75.56%).In terms of pulmonary function indexes,patients in the experimental group showed significant improvement after treatment,especially the increase in forced expiratory volume and forced vital capacity,while these improvements were not as obvious in the control group.In addition,the incidence of adverse reactions was significantly lower in the experimental group than in the control group,suggesting that the application of NIPPV is relatively safe.Quality of life assessment also showed that patients in the experimental group had significantly better quality of life than the control group after treatment.Conclusion:This study demonstrated the effectiveness of NIPPV as an adjunctive treatment for severe bronchial asthma combined with respiratory failure.NIPPV can improve lung function,reduce the incidence of adverse effects,increase the overall effectiveness of the treatment,and contribute to the improvement of patients'quality of life.Therefore,NIPPV should be regarded as an effective and safe treatment in clinical management,especially in patients with severe bronchial asthma combined with respiratory failure,where its application has potential clinical significance.

Relationship Between Gene-Phenotype and Clinical Manifestations of Chromosomal Copy Number Variations Indicated by Non-Invasive Prenatal Testing

Objective:To analyze the clinical value of non-invasive prenatal testing(NIPT)in detecting chromosomal copy number variations(CNVs)and to explore the relationship between gene expression and clinical manifestations of chromosomal copy number variations.Methods:3551 naturally conceived singleton pregnant women who underwent NIPT were included in this study.The NIPT revealed abnormalities other than sex chromosome abnormalities and trisomy 13,18,and 21.Pregnant women with chromosome copy number variations underwent genetic counseling and prenatal ultrasound examination.Interventional prenatal diagnosis and chromosome microarray analysis(CMA)were performed.The clinical phenotypes and pregnancy outcomes of different prenatal diagnoses were analyzed.Additionally,a follow-up was conducted by telephone to track fetal development after birth,at six months,and one year post-birth.Results:A total of 53 cases among 3551 cases showed chromosomal copy number variation.Interventional prenatal diagnosis was performed in 36 cases:27 cases were negative and 8 were consistent with the NIPT test results.This indicates that NIPT’s positive predictive value(PPV)in CNVs is 22.22%.Conclusion:NIPT has certain clinical significance in screening chromosome copy number variations and is expected to become a routine screening for chromosomal microdeletions and microduplications.However,further interventional prenatal diagnosis is still needed to identify fetal CNVs.

改进ICP算法的激光雷达点云配准

针对传统ICP算法在激光雷达目标点云配准中存在匹配时间长,以及受初值影响导致该算法应用在无人车SLAM技术中容易存在定位精度不高和稳健性较差的问题,本文提出了一种结合KD-tree算法的NDT-ICP算法。首先,通过Voxel Grid滤波对激光雷达获取的点云数据进行预处理,利用平面拟合参数的方法去除地面点云;然后,利用NDT算法进行点云粗匹配,缩短目标点云与待匹配点云距离;最后,通过KD-tree邻近搜索法提高对应点查找速度,并通过优化收敛阈值,完成ICP算法的精匹配。试验结果表明,本文提出的改进算法相比于NDT算法和ICP算法,在点云配准速度和精度上有明显提高,且在地图构建上精度和稳健性更好。

ICP参数在闭合性颅脑创伤患者预后评估中的应用价值

目的探究颅内压(ICP)参数在闭合性颅脑创伤患者预后评估中的应用价值。方法脑外伤患者100例入组后均接受ICP监测,依据类型分为闭合性脑创伤组(n=48)、开放性脑创伤组(n=52),依据闭合性脑创伤患者预后分为预后良好组(n=17)、预后不良组(n=31)。比较各组ICP参数,分析闭合性颅脑创伤患者预后影响因素和ICP参数预测患者预后的价值。结果闭合性脑创伤组ICP、RAP、AMP较开放性脑创伤组明显高,CPP较开放性脑创伤组明显低(P<0.05)。ROC曲线分析提示ICP、CPP、RAP、AMP联合检测诊断闭合性脑创伤不良预后的敏感度为86.1%,曲线下面积为0.833。结论闭合性颅脑创伤患者颅内压明显高于开放性颅脑创伤者,ICP参数联合检测对闭合性颅脑创伤患者预后有较高预测价值。

电感耦合等离子体质谱(ICP-MS)法测定闪长岩中的高场强元素

闪长岩中高场强元素主要赋存在难溶的矿物(角闪石、锆石等)中。采用常规的密闭酸溶法导致高场强元素特别是锆、铪元素溶出率偏低。针对这一问题,根据高场强元素的赋存状态,首先增加预消解过程,其次对溶解样品所需试剂添加量(氢氟酸、硝酸)以及消解时间设计了3因素3水平的正交实验,从而得到最佳试剂添加量为2 mL氢氟酸和1 mL的硝酸,消解时间为36 h,影响高场强元素溶出率的最主要因素是氢氟酸。以在最佳前处理实验方案下溶样,在所溶解完全的溶液介质中添加浓度为0.1%的盐酸(体积比),以保证高场强元素在溶液里的稳定性。建立的方法用于北山地区闪长岩样品分析,并与碱熔、X射线荧光光谱法测定值对比,分析结果具有良好的一致性,方法检出限0.004~2.5μg/g,相对标准偏差1.5%~8.4%,加标回收率93.0%~108%。实现了闪长岩中高场强元素的准确分析。

电感耦合等离子体发射光谱(ICP-OES)法测定陕西眉县猕猴桃矿物质含量及相关营养评价

为探究陕西眉县所产猕猴桃中矿物质含量及评价其相关营养价值。利用电感耦合等离子体发射光谱(ICP-OES)法对陕西眉县主产的徐香、翠香、红心、黄心四个品种猕猴桃中9种矿物质含量进行测定,并采用营养质量指数法(Index of nutritional quality,INQ)对矿物质元素进行营养评价,同时应用SPSS软件对9种矿物质和能量进行相关性分析。陕西眉县四个品种猕猴桃矿物质均以钾、磷、钙、镁四种元素为主,约占总矿物质的99.8%,四个品种中INQ均大于1的矿物质有钙、钾、镁、铜,其中钾的INQ最高在3.89~5.19。矿物总量最高的品种为翠香328 mg/100g,但营养质量指数最高的为徐香16.78(INQ_(总))。通过相关性分析表明各元素间存在着不同程度的相关性,其中钾与能量的相关系数最高为0.982。猕猴桃是一种高钾低钠的优质食品,不同品种猕猴桃矿物质元素的营养价值差异明显,矿物质营养密度最高的为翠香,其次为红心、黄心、徐香,但从营养价值指数方面来看,徐香最高,翠香次之,红心和黄心猕猴桃矿物营养水平稍逊。

孕期发生ICP的风险因素分析

目的分析妊娠期发生ICP的相关风险因素,对妊娠期发生ICP的风险进行早期预测。方法收集2018年5月至2023年5月上海市公共卫生临床中心收治的300例妊娠期肝内胆汁淤积症病例为ICP组,同期收治的300正常孕妇为对照组,临床病例资料完整,进行回顾性分析。结果ICP组孕妇的临床特征中年龄大于30岁、既往ICP病史、皮肤瘙痒、孕前BMI>24、妊娠期高血糖、甲状腺疾病、辅助生殖及多胎发生率明显高于对照组,差异有统计学意义(P<0.05),以上临床特征指标是孕期发生ICP的风险因素。临床特征构建的列线图可以预测发生ICP的风险。Lasso-Logistic回归分析结果显示化验指标肝功能(ALT、TBIL)、血脂(TG)、凝血功能(FIB)是孕期发生ICP的风险因素(P<0.05)。以上化验指标绘制的ROC曲线对发生ICP的风险有较好的预测价值。结论孕妇的部分临床特征及化验指标(ALT、TBIL、TG及FIB)是孕期发生ICP的风险因素。

基于破乳诱导萃取和ICP-MS/MS分析渣油中的微量金属元素

基于破乳诱导萃取提出利用电感耦合等离子体串联质谱(ICP-MS/MS)测定渣油中多种金属元素的新策略。渣油样品经二甲苯稀释降低黏度后采用质量分数6%的Triton X-114乳化,超声水浴破乳25 min,利用体积分数40%的盐酸萃取渣油中金属元素至水相,采用ICP-MS/MS测定其中10种金属元素Na、Mg、Al、Ca、V、Cr、Fe、Ni、Cu、Zn的含量。详细评估了破乳诱导萃取条件对渣油中金属元素萃取效率的影响,在串联质谱(MS/MS)模式下,利用氦碰撞气或不同反应气消除了金属元素的质谱干扰,采用标准参考物质NIST SRM 1634c(燃油中的微量元素)验证了方法的准确性,以微波消解技术处理渣油样品并采用扇形磁场电感耦合等离子体质谱(SF-ICP-MS)进行对比分析验证了方法的可靠性。结果显示,金属元素在各自的含量范围内呈现良好的线性关系(线性相关系数≥0.9997),检出限(LOD)为2.05~31.4 ng/L,NIST SRM 1634c的测定结果与标准参考物质提供的认证值及文献报道的参考值基本一致,置信度水平达到95%,ICP-MS/MS方法与SF-ICP-MS的对比分析结果无显著性差异。所建立的ICP-MS/MS方法操作简单,分析速率快,准确可靠性好,已用于渣油中多种金属元素的质量评价。

基于ICP-MS研究转炉钢渣微粉吸附镍和铅的动力学机理

随着工业化的发展,水体和土壤中的重金属污染日益严重。其中,重金属镍是一种常见的致敏性金属,会引起人体过敏发炎,甚至会引发癌症;血液中铅浓度的超标会危害人的神经系统、心血管系统和生殖系统,造成终身性的危害。因此,治理镍和铅重金属污染具有十分重要的意义。钢渣是炼钢过程中产生的一种副产物,其存在难以利用与附加值低的问题。同时加之管理制度的不健全,导致大量钢渣露天堆放,对土地资源、地下水源,以及空气质量造成严重影响。钢渣微粉具有比表面积大、多孔、化学活性高等特性,被广泛利用,可以成为吸附材料。本文以转炉钢渣微粉为研究对象,利用激光粒度仪、电感耦合等离子体质谱仪、比表面积与孔隙度吸附仪、X射线荧光光谱仪等测试转炉钢渣微粉的基本性质,重点研究转炉钢渣微粉添加量、重金属初始浓度、溶液pH和吸附时间对转炉钢渣微粉吸附Ni^(2+)、Pb^(2+)的效果,结合吸附动力学与吸附等温线理论揭示转炉钢渣微粉对Ni^(2+)、Pb^(2+)的吸附作用机理,为处理镍、铅重金属污染和工业废水处理提供技术支持与理论依据。结果表明:当转炉钢渣微粉添加量大于12.5 g·L^(-1)、重金属初始浓度小于100 mg·L^(-1)、溶液pH大于3和吸附时间大于120 min时,转炉钢渣微粉对Ni^(2+)、Pb^(2+)的吸附效果良好,即基本达到90%。转炉钢渣微粉对Ni^(2+)、Pb^(2+)的吸附符合准二级动力学模型,吸附速率由边界扩散和颗粒内扩散共同控制,吸附过程以化学吸附为主。转炉钢渣微粉的结构具有多孔性为物理吸附Ni^(2+)、Pb^(2+)提供吸附空间,转炉钢渣微粉的化学成分不仅具有碱性与Ni^(2+)、Pb^(2+)形成络合产物,而且水化过程中CaO与SiO_(2)生成C—S—H凝胶,对Ni^(2+)、Pb^(2+)形成络合吸附与硅酸盐体系包裹。转炉钢渣微粉对Ni^(2+)、Pb^(2+)吸附可能存在多层吸附。吸附Ni^(2+)、Pb^(2+)的过程为优惠吸附,吸附容易进行,其理论最大吸附量分别为18.785和17.002 mg·g^(-1)。

ICP-MS与ICP-OES法测定疫苗中铝含量的比较

目的:比较电感耦合等离子体质谱法(ICP-MS)与电感耦合等离子体发射光谱法(ICP-OES)和《中国药典》2020年版滴定法用于含铝佐剂疫苗中铝含量的测定。方法:通过方法学验证和样品测定,对比分析两种方法的前处理方法、线性、重复性、准确度、定量限、检测限和样品测定结果,同时采用现行版《中国药典》收载的滴定法对典型样品进行检测,并对三种方法的分析条件和结果进行了对比。结果:ICP-OES的铝离子浓度在1~20μg·mL^(-1)线性关系良好,r为0.9999,6种疫苗中铝含量回收率在99%~104.6%范围内,RSD均低于3%(n=9);ICP-MS测得的铝离子浓度在2.5~80 ng·mL^(-1)线性关系良好,r为0.999,6种疫苗中铝含量回收率在99.4%~108.9%范围内,RSD均低于8%(n=9)。三种方法测得的铝含量结果略有差异,但未发现显著规律,相对偏差均小于10%,ICP-MS法、ICP-OES法及滴定法对疫苗中铝含量的检测结果基本一致。结论:ICP-MS和ICP-OES 2种方法均可用于含铝佐剂疫苗中铝离子含量的测定,两种检测方法简便、快速、准确。ICP-OES仪器成本较低,更易于实验室推广。

基于ICP-MS技术的六神曲中无机元素分析及其风险评估

对六神曲中无机元素进行分析并结合风险评估,为发酵类中药中有益元素的揭示、有害元素限量标准的制定提供依据。基于电感耦合等离子体质谱(ICP-MS)技术,对不同来源六神曲中无机元素进行含量测定,结合多元统计分析,对无机元素的特征进行表征,并对其进行初步风险评估。结果表明:六神曲中无机元素整体趋势一致,对比相关标准产六神曲生品发现,Zn、Ba、Cu为主要差异元素;按部颁标准产六神曲生品与麸炒品差异明显,Zn、Tl、Cu为特征差异元素;Cu、Cr、As为按《浙江省中药炮制规范》产六神曲生品与炒焦品中主要差异元素。风险评估结果提示,六神曲中有害元素的风险较低。方法稳定可靠,不同制法、不同炮制品六神曲中元素分布特征呈现出一定的规律性与差异性,其中重金属及有害元素的风险基本可控。研究结果可为六神曲质量控制体系的完善及安全性评价提供参考。