Minimising chemical hazards to improve biocompatibility of natural rubber latex products

This study examines the residual rubber chemicals commonly used in natural rubber (nr) latex formulation and their effects on the biocompatibility of finished products. several in-house compounds differing in chemical compositions were prepared and analysed for their physical properties,residual chemicals and biocompatibility. from this,an optimum formulation with low residual chemical content and acceptable physical properties was selected as a model design. in vitro cytotoxicity elution tests with l 929 fibroblasts showed all sample extracts to be poorly biocompatible. this however improved markedly when tested against extracts made from solid samples that had undergone a pre-wash in acetone. tensile strength and m300 values of the solid samples were within an acceptable range with minimal changes after the acetone wash. residual chemical content of the extracts was markedly reduced when analysed using high performance liquid chromatography based on the diethyldithiocarbamate (dec) derivative method. a further study on 12 commercial powder-free nr examination gloves showed a similar improvement after the acetone wash where cell viability of l 292 fibroblasts was substantially increased in tandem with reduced residual chemical content. a genotoxicity study on chang liver cells via the alkaline comet assay showed minimal dna damage. the physical properties of these gloves remained unaffected after the acetone wash.