Thermogravimetry/mass spectrometry is used to identify TG transitions corresponding to loss of residual moisture in freeze-dried biological products with complex TG curves. While TG weight losses were recorded, ion intensities of mass peaksm/e=18 (water) andm/e=44 (carbon dioxide) were monitored continuously for Typhoid Vaccine U.S.P., Meningococcal Polysaccharide Vaccine Groups A and C Combined and Honey Bee Venom Allergenic Extract. MS ion intensities indicated the difference between evolution of residual moisture and moisture associated with product thermal decomposition. Residual moisture values calculated from TG weight losses indicated by mass spectral data agreed with Karl Fischer moisture data.
Authors:J May, A Del Grosso, N Etz, R Wheeler, and L Rey
(TG), thermogravimetry/mass spectrometry (TG/MS), and loss-on-drying methodology
are used to provide residual moisture results for freeze-dried biological
products regulated by the US Food and Drug Administration. Residual moisture
specifications must be met in order to ensure freeze-dried biological product
potency and stability throughout the licensed product's shelf life.
TG, TG/MS, loss-on-drying and vapor pressure moisture measurements are compared
for a BCG Vaccine. Comparisons are made between residual moisture data for
the freeze-dried cake and vapor pressure moisture determinations in the space
above the freeze-dried cake in the final container. Vapor pressure moisture
precision data is presented for α-interferon and BCG vaccine. Impact
of residual moisture and vapor pressure moisture upon product stability is
Authors:J. May, A. Del Grosso, R. Wheeler, and N. Etz
A TA Instruments Thermal Analysis System (TG) has been interfaced to the Hewlett Packard 5972 quadrupole mass spectrometer.
An OSS-2 variable outlet splitter was plumbed between the TG and the mass spectrometer. This interface allows continuous monitoring
of the ion intensities of mass peaksm/e=18 (water) andm/e=44 (carbon dioxide) used to elucidate the TG transitions attributable to residual moisture in freeze-dried biological products.
Moisture specifications must be met in order to insure product stability throughout the approved shelf life. TG/MS results
are discussed for BCG Vaccine, BCG Live (Intravesical) and U. S. Standard Antihemophilic Factor. Karl Fischer and TG/MS moisture
results are compared.
Y-Ba-Cu oxalate powder with a presumed Y:Ba:Cu molar ratio of 1:2:4 was prepared by a modified co-precipitation method and
its solid-phase thermal decomposition was studied from 25 to 1000C, the major evolved gases being H2O and CO2. The air-dried powder contained residual moisture. It required isothermal heat treatment for elimination of the evolved gases.
The melting point of the co-precipitation Y-Ba-Cu oxalate powder, determined by DSC at a heating rate of 10C min−1 was approximately 882C in N2, 949C in air and about 979C in O2. The dependence of the sintering properties of this material upon the atmosphere and the temperature is considered.
The stabilities of protein based products in the freeze-dried state depend critically on the formulation and process variables temperature, pressure, time and moisture content. The principal determinants of biological stability are the glass/rubber transitions of the freeze concentrate and of the dried product and its residual moisture content. This paper describes the role of DSC in the investigation of the component processes which together form the basis of effective freeze-drying: a maximisation of yield, an optimum shelf life and a cost-effective process.
Authors:Shuang Hu, Yuan Hu, Lei Song, and Hongdian Lu
aspirated for 10 min to eliminate residualmoisture. AMEO (5.0 g) was added slowly at 0 °C for about 2 h, and the reaction mixture was stirred for another 2–3 h at room temperature. Then DOPO (10.80 g), triethylamine (0.2 g), and another dichloromethane (50
Authors:Dhruthiman R. Mantheni, M. P. K. Maheswaram, Hany F. Sobhi, Naullage Indika Perera, Alan T. Riga, M. Ellen Matthews, and K. Alexander
the determination of the amorphous and crystalline content in a solid dosage form.
The premelt behavior is significant in understanding solid state stability and reactivity. Premelt temperature range can identify residualmoisture. A
Authors:Peter S. Shuttleworth, Vitaly Budarin, and James H. Clark
K which also corresponds to a large, broad endothermic transition in the DSC trace. This loss is probably due to residualmoisture attached to the material coming off as the temperature of the environment is raised. The next event is an endothermic
Authors:M. L. S. De Melo, N. A. Santos, R. Rosenhaim, A. G. Souza, and P. F. Athayde Filho
extracted from dry seeds until residualmoisture of about 8% in a Soxhlet system with n -hexane as a solvent extractor. The percentage of lipid content was determined by gravimetric calculation methodology according to the Institute Adolfo Lutz [ 7
Authors:Agata Górska, Ewa Ostrowska-Ligęza, Karolina Szulc, and Magdalena Wirkowska
. Powders were further dried in a vacuum oven at 50 °C for 24 h before experiments were carried out to remove residualmoisture. The processes and analyses were carried out in triplicate.
DSC and MDSC studies