Differential Scanning Calorimetry of Cephalexin-Dextrose and Cephalexin-Aspartame Mixtures

Abstract

The possible interaction of cephalexin with anhydrous dextrose and with aspartame, in the solid state, was investigaged by comparing the thermal behavior of physical mixtures of the respective original components in different molar ratios, using differential scanning calorimetry. Both anhydrous dextrose and aspartame were found to form complexes with cephalexin. The stoichiometries of these complexes were found to be 1:1 molar complexes between cephalexin and anhydrous dextrose and 4:1 and 1:1 molar complexes between cephalexin and aspartame. Complexed cephalexin was found to decompose at markedly lower temperatures than uncomplexed cephalexin.     

Compatibility Study of Propoxyphene HCL Solid Mixtures Using Differential Scanning Calorimetry

Abstract

Differential scanning calorimetry was used to investigate the compatibility of propoxyphene HCl-aspirin and propoxyphene HCl-acetaminophen solid mixtures. It was found that the interaction of propoxyphene HCl with aspirin and acetaminophen caused an eutectic mixture. Acetaminophen and propoxyphene HCl showed no degradation in the eutectic mixtures as detected by high performance liquid chromatography.     

Differential Scanning Calorimetry of Aspartame-Caffeine Mixture

The possible interaction between aspartame and caffeine was investigated by comparing the thermal behavior, using differential scanning calorimetry, of physical mixtures of aspartame and caffeine along with mixtures, in the same molar ratios, obtained as the co-precipitate. Caffeine was found to form several complexes with aspartame. These complexes were found to be dependent on the molar ratios of aspartame to caffeine. The stoichiometry of the aspartame-caffeine complexes were determined from the enthalpy change of the DSC transitions resulting from the complex formation.     

Differential Scanning Calorimetry of Ampicillin-Dextrose Mixture

The possible interaction of anhydrous ampicillin and ampicillin trihydrate with anhydrous dextrose, in the solid state, was investigated by comparing the thermal behavior, using differential scanning calorimetry, of physical mixtures of the respective original components in different molar ratios. Anhydrous dextrose was found to form complexes with anhydrous ampicillin and ampicillin trihydrate. These complexes were found to be dependent on the molar ratios of the mixture components. The stoichiometries of these complexes were determined from the enthalpy change of the DSC transitions of the mixtures and were found to be 1:1, 2:3 and 1:3 molar complexes between ampicillin, anhydrous and trihydrate, and anhydrous dextrose. Complexed ampicillin was found to decompose at markedly lower temperatures than uncomplexed ampicillin.     

Differential Scanning Calorimetry of Ampicillin-Dextrose Mixture

The possible interaction of anhydrous ampicillin and ampicillin trihydrate with anhydrous dextrose, in the solid state, was investigated by comparing the thermal behavior, using differential scanning calorimetry, of physical mixtures of the respective original components in different molar ratios. Anhydrous dextrose was found to form complexes with anhydrous ampicillin and ampicillin trihydrate. These complexes were found to be dependent on the molar ratios of the mixture components. The stoichiometries of these complexes were determined from the enthalpy change of the DSC transitions of the mixtures and were found to be 1:1, 2:3 and 1:3 molar complexes between ampicillin, anhydrous and trihydrate, and anhydrous dextrose. Complexed ampicillin was found to decompose at markedly lower temperatures than uncomplexed ampicillin.     

Differential Scanning Calorimetry of Ampicillin-Aspartame Mixture

The possible interaction of anhydrous and trihydrate ampicillin with aspartame, in the solid state, was investigated by comparing the thermal behavior of physical mixtures of the respective original components in different molar ratios, using differential scanning calorimetry. Aspartame was found to form complexes with anhydrous ampicillin and ampicillin trihydrate. These complexes were found to be dependent on the molar ratios of the mixture components. One of the complexes between anhydrous and trihydrate ampicillin and aspartame, as determined from the enthalpy change of the DSC transitions of the mixtures, was found to have a 2:1 molar ratio.     

Differential Scanning Calorimetry of Aspartame-Mannitol Mixture

Abstract

Differential scanning calorimetry was used to study both the qualitative and quantitative thermal properties of mixtures of aspartame with both mannitol and granular mannitol. Aspartame was found to be compatible with both forms of mannitol. No aspartame decomposition was observed in the preparation of a fused aspartame-mannitol mixture prepared at 161-165°C. L-(-)-leucine can be recommended as soluble lubricant for formulations containing aspartame and mannitol.     

Differential Scanning Calorimetry of Aspartame-Mannitol Mixture

Differential scanning calorimetry was used to study both the qualitative and quantitative thermal properties of mixtures of aspartame with both mannitol and granular mannitol. Aspartame was found to be compatible with both forms of mannitol. No aspartame decomposition was observed in the preparation of a fused aspartame-mannitol mixture prepared at 161-165°C. L-(-)-leucine can be recommended as soluble lubricant for formulations containing aspartame and mannitol.     

Differential Scanning Calorimetry of Ampicillin-Aspartame Mixture

Abstract

The possible interaction of anhydrous and trihydrate ampicillin with aspartame, in the solid state, was investigated by comparing the thermal behavior of physical mixtures of the respective original components in different molar ratios, using differential scanning calorimetry. Aspartame was found to form complexes with anhydrous ampicillin and ampicillin trihydrate. These complexes were found to be dependent on the molar ratios of the mixture components. One of the complexes between anhydrous and trihydrate ampicillin and aspartame, as determined from the enthalpy change of the DSC transitions of the mixtures, was found to have a 2:1 molar ratio.     

Studies of Ergotamine Tartrate-Caffeine Interactions by Differential Scanning Calorimetry

Differential scanning calorimetry was used to evaluate the interactions between ergotamine tartrate and caffeine. Physical mixtures of ergotamine tartrate and caffeine, as well as mixtures formed by evaporation of ergotamine tartrate and caffeine from a methanol solution, were evaluated. The preparation and characterization of eleven different molar ratios of ergotamine tartrate-caffeine complexes is described. The drug was found to interact with caffeine in the solid state with the formation of complexes. The mixture obtained from the methanol solution showed complexes with ergotamine tartrate-caffeine molar ratios of 2:3 and 2:15, with possible complexes having 1:10, 1:15 and 1:20 molar ratios. A phase diagram was constructed. Physical mixtures of the same molar ratios showed possible complex formation at molar ratios of 1:1, 1:1 and 1:3.     

Studies of Ergotamine Tartrate-Caffeine Interactions by Differential Scanning Calorimetry

Abstract

Differential scanning calorimetry was used to evaluate the interactions between ergotamine tartrate and caffeine. Physical mixtures of ergotamine tartrate and caffeine, as well as mixtures formed by evaporation of ergotamine tartrate and caffeine from a methanol solution, were evaluated. The preparation and characterization of eleven different molar ratios of ergotamine tartrate-caffeine complexes is described. The drug was found to interact with caffeine in the solid state with the formation of complexes. The mixture obtained from the methanol solution showed complexes with ergotamine tartrate-caffeine molar ratios of 2:3 and 2:15, with possible complexes having 1:10, 1:15 and 1:20 molar ratios. A phase diagram was constructed. Physical mixtures of the same molar ratios showed possible complex formation at molar ratios of 1:1, 1:1 and 1:3.     

差示扫描量热法在金属材料中的应用

综述了差示扫描量热法(DSC)在金属材料热物理性能测试及工艺制度制定方面的应用,包括熔融温度范围、熔化和结晶焓、钛合金相转变温度、铝合金均匀化温度以及比热容的测定,详细介绍了各种性能参数测试的方法和要点,并指出了DSC技术未来的发展趋势。     

Compatibility Study Between Naproxen and Tablet Excipients Using Differential Scanning Calorimetry

Differential scanning calorimetry (DSC) was used to investigate the physico-chemical compatibility between naproxen and a number of commonly used tablet excipients.

Interactions of naproxen with PVP, cross-linked PVP, Emcompress and the lubricants stearic acid, magnesium stearate and Precirol Ato 5 were found. Naproxen was found to be compatible with starch, Sta-Rx 1500, Primojel, Explotab, Avicel PH 101, Elcema G250, Ac-Di-Sol and Sterotex.     

Differential Scanning Calorimetry as a Quick Scanning Technique for Solid State Stability Studies

The potential compatabilities of various commonly used excipients with Indomethacin (IMC) were compared using differential scanning calorimetry (DSC). Some agents were found to have no solid state interaction whereas others showed major changes in the thermograms signifying possible interactions in the solid state. The results show that DSC can be employed in preliminary preformulation studies for the evaluation of solid state interactions as an aid to excipient selection.     

Compatibility Study Between Ketoprofen and Tablet Excipients Using Differential Scanning Calorimetry

Differential scanning calorimetry was used to investigate the interactions between the drug ketoprofen and a number of commonly used tablet excipients. Ketoprofen was found to interact with Precirol Ato 5, magnesium stearate, Emcompress, PVP, cross-linked PVP and lactose.     

Compatibility Study Between Naproxen and Tablet Excipients Using Differential Scanning Calorimetry

Abstract

Differential scanning calorimetry (DSC) was used to investigate the physico-chemical compatibility between naproxen and a number of commonly used tablet excipients.

Interactions of naproxen with PVP, cross-linked PVP, Emcompress and the lubricants stearic acid, magnesium stearate and Precirol Ato 5 were found. Naproxen was found to be compatible with starch, Sta-Rx 1500, Primojel, Explotab, Avicel PH 101, Elcema G250, Ac-Di-Sol and Sterotex.     

Compatibility Study Between Clenbuterol and Tablet Excipients Using Differential Scanning Calorimetry

Abstract

In order to improve the formulation of clenbuterol, the physico-chemical compatibility between this drug and various excipients commonly used in manufacturing of tablets, was studied by Differential Scanning Calorimetry (DSC).

Using this method, clenbuterol was found to be compatible with talc, stearic acid, magnesium stearate and titanium dioxide, whereas an incompatibility was shown with maize starch, pregelatinized starch, sodium starch glicollate, polyvinylpyrrolidone, avicel PH 101 and lactose.     

Compatibility Study Between Famotidine and Some Excipients Using Differential Scanning Calorimetry

Abstract

Based on DSC thermograms, famotidine interacted with kollidon, primojel, crospovidone, emcompress or lactose. There were no interaction between famotidine and talc, Mg stearate or avicel PH 101. HPLC analysis confirmed these interactions between famotidine with emcompress and crospovidone.     

Compatibility Study Between Atenolol and Tablet Excipients Using Differential Scanning Calorimetry

In order to improve the formulation of atenolol the physico-chemical compatibility between the drug and various excipients, commonly used in tablet manufacturing, was studied with the aid of Differential Scanning Calorimetry (DSC).

Using this method, it was found that atenolol is compatible with starch, Sta-Rx®, Primojel®, Avicel PH®, Ac-Di-Sol®, cross-linked PVP, magnesium stearate, calcium sulphate dihydrate, dicalcium phosphate and icing sugar. Interactions of atenolol with PVP, lactose and the lubricant stearic acid were found, although it cannot be conlusively stated that interaction incompatibilities will occur during storage at room temperature.     

Compatibility Study Between Clenbuterol and Tablet Excipients Using Differential Scanning Calorimetry

In order to improve the formulation of clenbuterol, the physico-chemical compatibility between this drug and various excipients commonly used in manufacturing of tablets, was studied by Differential Scanning Calorimetry (DSC).

Using this method, clenbuterol was found to be compatible with talc, stearic acid, magnesium stearate and titanium dioxide, whereas an incompatibility was shown with maize starch, pregelatinized starch, sodium starch glicollate, polyvinylpyrrolidone, avicel PH 101 and lactose.