An off-white polymer was obtained after drying the product overni

An off-white polymer was obtained after drying the product overnight in vacuo (111.8g, yield = 93%). 1H NMR (d6-DMSO) δ 12.2 (10H), 9.1 (10H), 8.51–7.71 (50H), 6.96 (40H), 6.59 (40H), 4.69–3.96 (60H), 3.81–3.25 (1500H), 3.06–2.65 (60H), 1.0–0.43 (180). 1H NMR (d6-DMSO) δ 171.9, 171, 170.5, 170.3, 155.9, 130.6, 129.6, 127.9, 115.3, 114.3, 70.7, 69.8, 54.5, 51.5, 50, 49.8, 49.4, 36.9, 36, 24.3, 23.3, 22.3, 21.2. IR (ATR) 3290, 2882, 1733, 1658, 1342, 1102, 962cm−1. The

final composition of the polymer is N3-PEG12K-b-poly(Asp)10-b-poly(Tyr20-co-D-Leu20)-Ac, Inhibitors,research,lifescience,medical which is also referred to as poly(ethylene glycol)-b-poly(aspartic acid)-b-poly(D-leucine-co-tyrosine). 2.3. Micelle Production All formulations were prepared using oil-in-water emulsion techniques involving Inhibitors,research,lifescience,medical dissolving the polymer in water and the drug in an organic solvent. An exemplary formulation technique for daunorubicin follows. The IVECT triblock copolymer (3g) was dissolved in water (500mL). Daunorubicin (301mg) was dissolved in dichloromethane (48mL) and methanol (12mL). Just prior to use, triethylamine (0.28mL) was added to the organic solution to complete the dissolution of the daunorubicin. The aqueous Inhibitors,research,lifescience,medical solution was mixed with a Silverson LRT-4 shear mixer (fine emulsor screen, 10,000RPM). Daunorubicin was added to the mixed solution in a single portion over ~10s. The solution was mixed

for an additional minute and then stirred at room temperature overnight. The resulting solution was then filtered through a 0.22μm PES filter (Millipore Stericup). Iron (II) chloride solution was added to the concentrated micelle Inhibitors,research,lifescience,medical solution at a concentration of 10mM, and the pH was adjusted to 8.0 and stirred overnight. This solution was frozen on a shell freezer at −40°C and then lyophilized on a Labconco 6L Plus manifold lyophilization system operating at a pressure of 0.050Torr and a collector temperature of −85°C. After 48h, crosslinked, Inhibitors,research,lifescience,medical daunorubicin-loaded micelles were recovered as a purple powder (3.22g, 93% yield). 2.4. Drug Weight Loading by HPLC The mass percentage

of active drug within the formulation was determined by HPLC. An exemplary procedure for daunorubicin follows. The daunorubicin-loaded micelle was analyzed by a Waters Alliance separations module (W2695) equipped with Waters Novapak C18, 4μm column (no. WAT086344) coupled with a Waters Photodiode Array Detector (W2998). Daunorubicin was detected at an absorbance of 480nm. Mobile phase consisted of a 10:70:20 ratio of methanol:10mM Cilengitide phosphate buffer pH 2.0:acetonitrile over a 10-minute gradient. Known standards of free daunorubicin were used to determine the percentage by weight of daunorubicin in the formulation (wt/wt%). 2.5. Particle Size Analysis Particle sizes were determined using dynamic light Belinostat side effects scattering on a Wyatt DynaPro (Santa Barbara, CA). Following lyophilization, micelles were dissolved at 1mg/mL in 150mM NaCl and were centrifuged at 2,000 RPM prior to analysis to remove dust. 2.6.

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