Development and in vitro evaluation of polyurethane microparticles as carrier for bevacizumab: an alternative treatment for retinopathy of prematurity

Abstract

Retinopathy of prematurity (ROP) is known as an abnormal development of the blood capillaries from the eyes’ retina, and it is met to those infants that were born too early (premature) as its name suggests. Bevacizumab or Avastin belongs to the class of monoclonal antibodies and it is a possible treatment for those patients who have been diagnosed with a recurrent malignant glioma or other cancers due to its behavior to bind selectively to vascular endothelial growth factor (VEGF). In this study, eye drops based on a polyurethane carrier used for bevacizumab were obtained and the degradation of this carrier was studied for three weeks in two different media: simulated body fluid (SBF) and phosphate buffered saline (PBS); the influence of ultrasounds on the degradation of polyurethane carrier was also evaluated. The obtained results suggest that the polyurethane carrier presents a very slow degradation which is beneficial for drugs which require low release rates and on the other hand, the concentrations of the degradation products remain at a low level.DOI: http://dx.doi.org/10.3329/icpj.v3i6.18759 International Current Pharmaceutical Journal, May 2014, 3(6): 275-279

Synthesis and characterization of a polyurethane carrier used for a prolonged transmembrane transfer of a chili pepper extract

“…The evaluation of the release rate of CAPs from the PU microparticles was performed using a procedure previously described in the literature by Albulescu et al 26 It is known that luteolin-rutinoside, luteolin-glucoside, myricetin, and kaempferol derivatives from chili pepper extracts are detected at 350 nm. 27 An UVi Line 9400 Spectrophotometer (SI Analytics, Germany) and Beer-Lambert law were used to determine the free CAPs content at every third day for 2 weeks while PU microparticles with chili pepper extract were maintained in a degradation medium; a calibration curve (R 2 =0.983) was first drawn (Figure 1).…”

“…Based on this result, the content of extract released in the degradation medium was evaluated every third day for 15 days ( Figure 6B) according to the procedure described in the literature. 26 No important peaks were obtained by DSC analysis in the studied temperature range (Figure 7), which is explained by the stability of PU below 300°C; because of the low Tg values of PU materials, around 5°C, which is explained by the decomposition of urethane and ether bonds, which results in a lower rigidity of chains. 32 Skin is an organ that responds very quickly to the exposure to an external aggressive agent such as sun radiation and chemical substances.…”

A Study on the Behavior of a Polyurethane Drug Carrier in Various pH Media

“…According to Albulescu et al, the size evolution in time of structures used as drug delivery systems can be used as a prediction parameter for the drug release rate [ 11 ], which is presumably the main parameter in the assessment of a drug carrier. It is known that a controlled release system allows the introduction of a drug into the body with improved effectiveness and safety by controlling the rate, the time interval, and the place of drug release inside the body [ 12 ].…”

Formulation and Characterization of Polyurethane Microstructures with Propolis Extract

“…The PU microstructures were synthesized following a multi-step process according to Albulescu et al (2014) with some modifications [15]. In brief, an organic phase (1.5 mL isophorone diisocyanate -IPDI mixed with 15 mL acetone) was treated with an aqueous phase (0.5 mL PEG 200, 1.5 mL EG, 3 mL Span ® 85 and 15 mL distilled water) at a temperature of 50 o C, under magnetic stirring (400-600 rpm) for 4 h. The two phases were prepared at 50!…”