TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal is chosen from silver and nanosilver formulations, zinc, copper, cobalt and nickel. The hyaluronic acid derivative is added with water in the form of bidistilled water, sodium hydroxide solution with a concentration of 0.075-0.75 M/l, or physiological solution. Preferred Method: The antibacterial agent is applied on prosthesis by immersing the prosthesis in hydrogel, or by spraying, spreading or brushing process.    TECHNOLOGY FOCUS - PHARMACEUTICALS - Preferred Components: The hyaluronic acid or its salt has a molecular weight of 100000-1500000 Da, preferably 200000-300000 Da. The antibiotic is chosen from tigecycline, daptomycin, telavancin, chloramphenicol, fusidic acid, bacitracin, rifampin, ethambutol, streptomycin, isoniazid, glycopeptides (including but not limited to teicoplanin and vancomycin), aminoglycosides (including but not limited to gentamicin, tobramycin, netilmicin and amikacin), cephalosporins (including but not limited to cefazolin, cefoxitin, cefotaxime, cefuroxime and moxalactam), macrolides (including but not limited to erythromycin), oxazolidinones (including but not limited to linezolid), quinolones, polymyxins, sulfonamides, tetracyclines and penicillins, and antifungal agent chosen from polyene antifungals, imidazole and triazole antifungals, allylamines, echinocandins and griseofulvin. The composition comprising antibacterial agent is solution or suspension. Preferred Composition: The concentration of hyaluronic acid derivative or its salt is 2-10 weight/volume%. The ratio of D-glucuronic acid units (grafted with polyethylene glycol chain) to the total number of such units present in the hyaluronic acid chain is 5-20%.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The polyester is chosen from polylactic acid having molecular weight of 3000-150000 Da, polyglycolic acid having molecular weight of 1000-900000 Da, polycaprolactone having molecular weight of 3000-900000 Da, and their mixtures and copolymers. The chains of polyethylene glycol are grafted on hyaluronic acid or its salt. The polyethylene glycol has a molecular weight of 400-20000 Da. ACTIVITY - Antibacterial. No biological data given.    MECHANISM OF ACTION - None given.    ADMINISTRATION - The antibacterial hydrogel is administered by injection. No dosage details given.    EXAMPLE - No suitable example given.