差示扫描量热法在脂质体研究中的应用

差示扫描量热法(differential scanning calorimetry，DSC)是在差示热分析(DTA)基础上发展起来的一种热分析方法，本文对近年来有代表性的DSC在脂质体研究中应用的文献进行分析归纳，综述了DSC考察脂质体制备方法过程中结构的变化、药物与脂质体的相互作用、高分子聚合物对脂质体渗透性的影响、表面活性剂对脂质体柔性的影响等研究中的应用，为脂质体的深入研究提供有价值的参考资料。     

差示扫描量热法在药剂学研究中的应用

综述了近年来差示扫描量热法在药剂学研究中的应用，包括在制剂开发前了解药物和辅料的物理性质、考察辅料与主药间或料间是否有相互作用、制剂工艺优化及处方筛选、制剂质量评价以及研究药物对皮肤的透过机理等方面的应用。     

差示扫描量热法在药物多晶型定量分析中的应用

药物多晶型直接影响药物的安全性和质量可控性。因此仅对药物进行晶型的定性研究已不能满足要求。为了确保药品的疗效及安全性,测定原料药或制剂中有效晶型含量需要采用适当的方法对多晶型进行定量分析。本文具体综述了近年来传统差式扫描量热法、调制式差示扫描量热法及超高效差示扫描量热法在药物多晶型定量分析方面的应用,并对其优缺点进行了总结,展望了其应用前景。     

差示扫描量热法测定7种药物纯度

目的 用差示扫描量热（DSS）法测定药物纯度及探讨影响测定结果的因素。方法用DSC法测定吲哚美辛等7种不同类别药物的纯度，并与《中国药典》规定方法结果进行对照。结果DSC法测定药物纯度的准确性好；试药的用量、纯度、升温速度对测定结果产生影响。结论本法测定高纯度药物简便、结果准确。     

差示扫描量热法测定药物纯度

目的 研究用差示扫描量热（DSC）法测定药物纯度的可靠性及影响测定的因素。方法 用DSC法测定吲哚美辛等7种不同类别的药物纯度，并与药典规定方法结果进行对照。结果 DSC法测定药物纯度的准确性好；试样的用量、纯度、升温速度对测定结果产生影响。结论 本法测定高纯度药物简便、结果准确。     

差示扫描量热法测定7种药物纯度

目的用差示扫描量热(DSC)法测定药物纯度及探讨影响测定结果的因素。方法用DSC法测定吲哚美辛等7种不同类别药物的纯度,并与《中国药典》规定方法结果进行对照。结果DSC法测定药物纯度的准确性好;试药的用量、纯度、升温速度对测定结果产生影响。结论本法测定高纯度药物简便、结果准确。     

差示扫描量热法测定肌醇纯度

目的:使用差示扫描量热法(DSC)对肌醇纯度进行测定。方法:使用密封式铝坩埚封装样品,测定的最佳条件为升温速率约1℃·min~(-1) ,样品量约2.5 mg,氮气流速为20～40 mL·min~(-1)。结果:纯度测定的PSD为0.02％,通过F检验及t检验,该方法与药典法无显著差异。结论:该方法简便、快速、准确,适合肌醇产品的定量测定。     

差示扫描量热法测定磺胺类化学对照品的纯度

目的 采用差示扫描量热法(differential scanning calorimetry,DSC)测定磺胺类化学对照品纯度。方法 采用优化DSC实验参数,载气流速50 mL·min^-1,升温速率3 ℃·min^-1,称样量1.3~2.0 mg,对7种磺胺类化学对照品进行纯度分析。结果 DSC测得磺胺噻唑纯度为99.9%,磺胺甲二唑为99.9%,磺胺甲氧嗪为99.8%,磺胺嘧啶为99.8%,磺胺甲噁唑为99.9%,磺胺多辛为99.5%和磺胺二甲嘧啶为99.9%,其结果与质量平衡法测定结果基本一致。结论 DSC简便、快捷、无需标准物质,为磺胺类化学对照品纯度测定提供了新的检测方法。     

差示扫描量热法在药品检验中的研究进展

差示扫描量热分析（DSC）具有简便快速、重现性好、且避免繁杂的样品制备过程等优点。本文着重综述了近年来DSC在包括纯度测定、晶型表征、熔点检测、热稳定性检查和中药定性定量分析等药品质量控制研究中的多方面应用进展情况,并展望了其未来发展前景。     

采用差示扫描量热技术建立苦参碱纯度测定新分析方法

目的研究采用差示扫描量热技术（DSC）,建立中药活性成分苦参碱化学样品纯度的新检测分析方法。方法针对苦参碱化学样品,考察了溶剂残留、炉体气氛、升温速率、称样量四个因素对差示扫描量热法检测结果的影响;优化并确定了最佳检测条件,测定了苦参碱化学样品的纯度值;利用高效液相色谱法（HPLC）对建立的方法及检测结果进行了验证。结果本研究建立的差示扫描量热法进行苦参碱样品纯度检测具有较高的科学性和可行性,最佳实验条件为升温速率4.0K/min,称样量为2.5mg～3.7mg,炉内气体为静态空气,经检测获得苦参碱样品的化学纯度值为99.818%;高效液相色谱法测得苦参碱样品化学纯度值为99.825%。结论利用建立的差热扫描量热分析方法可以快速、准确地测定苦参碱化学纯度,论文研究为苦参碱纯度测定提供了一种新分析技术和方法。     

Raman detected differential scanning calorimetry of polymorphic transformations in acetaminophen

Acetaminophen is known to crystallize in three polymorphic forms. Thermally induced transformations between the crystalline forms and the super-cooled liquid have been observed by differential scanning calorimetry (DSC), but the assignment of calorimetric transitions to specific polymorphic transformations remains challenging, because the transition temperatures for several transformations are close to one another, and the characteristics of the observed transitions depend on experimental variables that are often poorly controlled. This paper demonstrates the simultaneous application of DSC and Raman microscopy for the observation of thermally driven transitions between polymorphs of pharmaceutical materials. Raman detected differential scanning calorimetry (RD-DSC) has been used to monitor the DSC thermograms of super-cooled liquid acetaminophen and confirms the assignment of two exothermic transitions to specific polymorphic transformations. Principal component analysis of the Raman spectra have been used to determine the number of independent components that participate in the phase transformations, and multivariate regression has been used to determine transition temperatures from the spectral data. The influence of the laser excitation source on measured DSC thermograms has also been investigated, and it has been demonstrated that a baseline shift occurs in RD-DSC when a polymorphic transformation occurs between crystalline and amorphous forms. RD-DSC has been used to examine the influence of sample aging and sample pan configuration on the observed polymorphic transformations, and both of these variables were found to influence the thermal behavior of the sample. The results demonstrate the advantage of simultaneous Raman spectroscopy and differential scanning calorimetry for the unambiguous assignment of thermally driven polymorphic transformations.     

Quantitative crystallinity determination for E1010, a novel carbapenem antibiotic, using differential scanning calorimetry

Objectives The objective of this study was to develop a quantitative crystallinity analysis method for the bulk drug of E1010 ((+)‐(4R,5S,6S)‐6‐[(R)‐1‐hydroxyethyl]‐3‐[(2S,4S)‐2‐[(R)‐1‐hydroxy‐1‐[(R)‐pyrrolidin‐3 ‐yl]methyl]pyrrolidin‐4‐yl]thio‐4‐methyl‐7‐oxo‐1‐azabicyclo[3.2.0]hept‐2‐ene‐2‐carboxylic acid monohydrochloride), a novel carbapenem antibiotic. Methods X‐ray analyses, thermal analyses and hygroscopicity measurements were used to elucidate the crystal structure and the solid state properties. To develop a quantitative method for the crystallinity of E1010 bulk drug, the relationship between enthalpy change obtained by differential scanning calorimetry (DSC) and crystalline form ratio was investigated. Key findings E1010 bulk drug was found to exist in a crystalline trihydrate formed in two layers, i.e. a layer of E1010 free form, and a layer consisting of chloride ions and water molecules. The thermal analysis showed an endothermic peak derived from dehydration with the loss of crystal lattices at around 100°C as an onset. The enthalpy change value for the endothermic peak correlated well with crystalline content in binary physical mixtures of the crystalline trihydrate and the amorphous form. In addition, for nine lots of the bulk drug, a positive correlation between the enthalpy change and chemical stability in the solid state was observed. Conclusions This quantitative analysis of crystallinity using DSC could be applicable for the quality control of the bulk drug to detect variability among manufacturing batches and to estimate the chemical stability of partially amorphous samples.     

用差热“三点法”考查水溶性维生素药物间的相互作用

根据物理化学原理,结合相图对相互作用分类,提出用差效“三点法”考查药物的相互作用。并用此考查了水溶性维生素药物VB₁,VB₂,VC和烟酰胺之间的相互作用,结果表明,VC与烟酰胺有较强的相互作用,且与VB₁有一定相互作用,在复合维生素BC片中,VC不宜与其它维生素配伍。用差热“三点法”考查相互作用,信息多、范围宽、准确性高,具有实用价值。本文还提出了“三点法”的简易判别法则。     

Applications of thermal analysis in the pharmaceutical industry

Thermal analysis includes all methods measuring some parameter during the heating of a sample. Differential scanning calorimetry (or differential thermal analysis) where the parameter is heat flow into and out of the sample and thermogravimetry where the parameter is the weight change of the sample are of great value for the pharmaceutical industry.

Characterisation of drug substance, excipients, and packaging material: identification, purity, polymorphism, solvation, stability, , may be routinely done. Further examples demonstrating the use of these methods for the development of the dosage form are given: choice of the salt form, phase-diagrams, drug substance—excipient interactions, physical changes on processing or during storage, and even analysis of the dosage form.     

Thermal conductivity measurements for small molecule organic solid materials using modulated differential scanning calorimetry (MDSC) and data corrections for sample porosity

A method for measuring the thermal conductivity (k) of small molecule organic solid materials using modulated differential scanning calorimetry (MDSC) is demonstrated. Sample preparation required powder consolidation, unavoidably introducing air voids into compacts. Supporting equations for the technique were modified to include a porosity term (?), and the theoretical quadratic relationship between k and ? was confirmed by experimental measurements for 18 representative materials. Zero-porosity extrapolation was used to approximate values of “true” thermal conductivity for non-porous solids (k_?=0). Zero-porosity-extrapolated values ranged from 0.1273 W/(K m) to 0.3472 W/(K m) for all materials, consistent with expected values of k for non-porous organic polymers.     

Interaction of the chlorinated hydrocarbon insecticide lindane or DDT with lipids--a differential scanning calorimetry study

The interaction of DDT and lindane with glycosphingolipids and phospholipids was investigated by employing differential scanning calorimetry. The degree of perturbation produced by lindane is stronger than that of DDT and depends also on the lipid.