Abstract
Problem statement: Polystyrene failed to provide any reactive functionality of surface hydrophilicity that is capable of binding proteins. It is known that polystyrene must be chemically modified to make its surface amenable to covalent crosslinking with protein. Approach: The aim of this study was to investigate the effects of UV/ozone treatment on gelatin coating. The surfaces of microsize polystyrene beads (150 µm) were modified by UV/ozone treatment system at different treatment time, ozone flow-rate and UV intensity was analyzed by Design expert software. The treated beads were characterized with ATR-FTIR analysis to determine the introduction of carbonyl (-C=O), carboxylic group (-COOH) and amide group (-CO-NH2) onto the polystyrene surface. Sample characterization was also carried out by SEM and densitometer. Gelatin immobilization was then preceded by incubating treated PS sample in gelatin solution and the total amount of gelatin coated on the modified surface was identified by Bradford assay. Results: The maximum amount of gelatin obtained was 63.75 µg mL-1 while the lowest amount obtained for untreated PS (9.947 µg mL-1). The introduction of carbonyl, hydroxyl and amide group on the polystyrene beads surface was confirmed by ATR-FTIR analysis and thus measures the importance of UV/ozone treatment. Conclusion: From the results, it has been found that time is the most significant factor to prepare samples for gelatin immobilization at reduced flow rate and at an increased Ultraviolet (UV) intensity in the ranges of study.
Highlights
Immobilized proteins are used in many biochemical applications and often the amount of protein attached to the surface must be determined (Orschel et al, 1998)
UV was irradiated from both sides with three 6 W low-pressure mercury lamps (UV lamps) at a wavelength of 254 nm and at a constant radiation of 22 m W cm−2 and maintaining a Quantifying immobilized gelatin: Immobilized gelatin was analyzed by the method suggested by Gosnell and Mottola (1988) and Lu et al (2007). 50 mg of covalently coated polystyrene was covered with 200 μL of the Coomasie blue dye solution and the sample was shaken for 30 min at room temperature and rinsed with the washing solution to remove the dye which was not bound to the immobilized proteins
The effects of time (A) ozone flowrate (B) and UV intensity (C) on the amount of immobilized gelatin were analyzed by statistical software Design Expert, giving the main effects, the variance and the interaction between the effects acting in the coating of bovine gelatin on UV/ozone modified PS particles
Summary
Immobilized proteins are used in many biochemical applications and often the amount of protein attached to the surface must be determined (Orschel et al, 1998). It is well known that adsorption of protein is affected by wet ability of surfaces on substrates. Polymer particles can be covalently binding with gelatin either directly or indirectly by the aid of cross linking agent. Polymers which make covalent bonding directly with gelatin include monomers with an active halogen atom, epoxies and compounds containing aldehyde group. Polymers are capable of making covalent bonding with gelatin through the use of a cross linking agent which includes carboxylic acid containing group, amine containing monomers and active methylene group containing monomers
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
