Preparation of photo-patterned polymer–hydroxyapatite composites

A polymer–hydroxyapatite (HAp) composite is useful as hard tissue engineering scaffold materials for bone and teeth, particularly. It is necessary to control the form of the composites precisely, because form of bone and teeth is unique and specific. We demonstrated that the shape of a base polymer film was controlled by a photo-pattering technique. Hybridization of the photo-patterned polymer film and HAp was performed by alternative soaking of the film into calcium chloride aqueous solution and phosphate buffer solution. Poly(vinyl alcohol) bearing trans-cinnamate moieties as chromophoric groups (P(VA-VCI)) was spin-coated on various substrates, glass, metals such as titanium, aluminum, stainless steel. The spin-coated film was covered with a patterned photo-mask, exposed by using UV lamp and finally developed by dipping into mixed organic solvent. The patterned P(VA-VCI) film was processed by the alternate soaking process for preparation of P(VA-VCI)–HAp composites. We confirmed that formation of HAp in the P(VA-VCI) film by infrared spectroscopy and X-ray diffraction technique. Microscopic observations of the photo-patterned P(VA-VCI)–HAp composites were also performed. The border line between the polymer–HAp composite film and the substrate is clearly observed even after the alternative soaking process. This method is a method for being very useful for producing the polymer–HAp composite with the form of thought way.