A hydrophilic polymer comprising pendent groups of the formula I:Formula IWherein:W is independently selected from –OH, -COOH,-SO3H, -OPO3H, -O-(C1-4alkyl), -O-(C1-4alkyl)OH, -O-(C1-4alkyl)R2, -O-(C2H5O)qR1–(C=O)-O-C1-4alkyl and –O-(C=O)C1-4alkyl； or a group –BZ； wherein –OH, COOH, O-PO3H and SO3H maybe in the form of a pharmaceutically acceptable salt；wherein:B is a bond, or a straight branched alkanediyl, oxyalkylene, alkylene oxaalkylene, or alkylene (oligooxalkylene) group, optionally containing one or more fluorine substituents； andZ is an ammonium, phosphonium, or sulphonium phosphate or phosphonate ester zwitterionic group；X is either a bond or a linking group having 1 to 8 carbons and optionally 1 to 4 heteroatoms selected from O, N and S；G is a coupling group through which the group of the formula I is coupled to the polymer and is selected from ether, ester, amide, carbonate, carbamate, 1,3 dioxolone, and 1,3 dioxane；R1is H or C1-4alkyl；R2is –COOH, -SO3H, or –OPO3H2q is an integer from 1 to 4；n is an integer from 1 to 4；p is an integer from 1 to 3； andn + p is from 2 to 5； andwherein -COOH, -OPO3H2and -SO3H as well as phenolic –OH maybe in the form of a pharmaceutically acceptable salt.一種親水性聚合物，其包含式I之側基：式I其中：W係獨立地選自-OH、-COOH、-SO3H、-OPO3H、-O-(C1-4烷基)、-O-(C1-4烷基)OH、-O-(C1-4烷基)R2、-O-(C2H5O)qR1、-(C=O)-O-C1-4烷基及-O-(C=O)C1-4烷基；或基團-BZ；其中-OH、COOH、O-PO3H及SO3H可呈醫藥學上可接受之鹽形式；其中：B為一鍵，或直鏈分支烷二基、氧基伸烷基、伸烷基氧雜伸烷基或伸烷基(寡氧雜伸烷基)，視情況含有一或多個氟取代基；且Z為銨、鏻或鋶之磷酸酯或膦酸酯兩性離子基團；X為一鍵或具有1至8個碳及視情況1至4個選自O、N及S之雜原子的連接基團；G為該式I之基團與該聚合物偶合所經由之偶合基團且係選自醚、酯、醯胺、碳酸酯、胺基甲酸酯、1,3-二氧雜環戊烯酮及1,3-二噁烷；R1為H或C1-4烷基；R2為-COOH、-SO3H或-OPO3H2；q為整數1至4；n為整數1至4；p為整數1至3；且n + p為2至5；且其中-COOH、-OPO3H2及-SO3H以及酚-OH可呈醫藥學上可接受之鹽形式。
