#Argen tandheelkundige legeringen software

In the presence of mechanical and thermal stress, all samples were readily soluble within two minutes, and degradation was observed immediately as indicated by the change in the light scattering signal. As shown in Figure 3, in the absence of mechanical stress (stirring), the polymer was soluble at all temperatures without any observed change in molecular weight and no indication of degradation. The polymer degradation curves were normalized to the initial mass of the polymer, and the normalized molecular weight was plotted versus time. The molecular weight was determined to be 5,500 g/mol. Figure 2: Debye analysis of a polystyrene sample with unknown molecular weight. The unknown PS sample was determined to have a molecular weight of 5,500 g/mol (Figure 2). Using this equation and a linear fit of the dilution data (Figure 1), the 16,500 g/mol and 18,500 g/mol standards were calculated to have molecular weights of 15,300 g/mol and 193,000 g/mol, respectively. When rearranged for single angle analysis at 90° and solving for weight average molecular weight, the equation becomes: If q 2(S 2) z << 1 (true for most polymers) and the sample is diluted such that, then the equation can be simplified to: Baseline scattering intensitiesĭebye analysis was used to determine the initial molecular weight of each sample, requiring several assumptions. The y-intercept yields the reciprocal of the molecular weight. The data is fit using a linear least squares regression. Figure 1: Debye analysis of a 16,500 g/mol polystyrene standard in THF. Each dilution was analyzed and monitored for at least three minutes to establish a stable baseline signal (Figure 1 – inset). Light scattering intensity was recorded for each dilution prior to data collection. Each sample was heated to 37☌ for five days using ARGEN’s temperature control feature. The pH of each solution was adjusted, providing a pH range = 1.54 – 5.85 (five data points) with a final = 1 mg/ml. Using Bovine Serum Albumin (BSA) as a model protein for aggregation and degradation, a = 2 mg/mL sample was prepared in 50 mM phosphate. Monitoring Biopolymer (Protein) Degradation Finally, three samples of PS-A were dissolved in toluene (Tol), butyl acetate (BAc), or THF and allowed to degrade at 55☌ with a stirring rate of 100 RPM for 10 hours. A subsequent experiment was performed with stirring (mechanical stress) at 100 RPM and thermally stressed from 30☌ – 55☌ for the entirety of the experiment.

These samples were then thermally stressed at a temperature range from 30☌ – 55☌ for 15 hours to monitor degradation. Samples of polystyrene (PS-A) were dissolved in THF at a = 10 mg/ml, placed into cuvettes, and loaded into ARGEN™ sample cells. Two Polystyrene (PS) standards, 16,500 g/mol and 185,000 g/mol, and an uncharacterized PS sample (PS-A) were serially diluted with tetrahydrofuran (THF) from 15.0 mg/mL to 0.166 mg/mL, generating an 8-point Debye plot for extrapolation of absolute molecular weight of each sample using the Debye equation:

#Argen tandheelkundige legeringen software

The ARGEN™ control software features an intuitive interface for all aspects of experimental design and independent control of each cell for parallel parameter adjustment and real-time data processing. This allows for a highly flexible approach to experimental design. The device is equipped with 16 independently controlled sample cells, permitting the user to establish thermal, chemical, and mechanical (stirring) stress parameters on each sample concurrently. These features enable teams to develop biologic formulations up to 16-fold faster.ĪRGEN™ utilizes fixed angle (90°), simultaneous multiple sample light scattering (SMSLS) technology which provides rapid, real-time, continuous data collection for characterizing qualitative and quantitative properties of target molecules. The instrument uses a multi-stressor testing platform powered by static light scattering detection and intuitive data processing. ARGEN™: Smart & Rapid Therapeutic Biopolymer DevelopmentĪRGEN™ is a high throughput tool for the rapid assessment of the stability and viability of therapeutic proteins, peptides, and biopolymers.