A water soluble conjugated polymer having the structure of Formula (Ia): wherein: (i) each R is independently a non-ionic side group selected from (CH 2) x (OCH 2 CH 2) y OCH 3 where each x is independently an integer from 0-20, each y is independently an integer from 0 to 50, or a benzyl optionally substituted with one or more halogen, hydroxyl, C 1 -C 12 alkoxy, or (OCH 2 CH 2) z OCH 3 where each z is independently an integer from 0 to 50, capable of imparting solubility in water in excess of 10 mg/mL; (ii) MU is a polymer modifying unit or band gap modifying unit that is selected from the group consisting of a'-k' having the structure: * = site for covalent attachment to unsaturated backbone wherein R is a non-ionic side group capable of imparting solubility in water in excess of 10 mg/mL; (iii) each optional linker L 1 and L 2 are aryl or hetroaryl groups evenly or randomly distributed along the polymer main chain and are substituted with one or more pendant chains terminated with a functional group selected from amine, carbamate, carboxylic acid, carboxylate, maleimide, activated esters, N-hydroxysuccinimidyl, hydrazines, hydrazids, hydrazones, azide, alkyne, aldehydes, thiols, and protected groups thereof for conjugation to another substrate, molecule or biomolecule; (iv) G 1 and G 2 are each independently selected from hydrogen, halogen,alkyne, optionally substituted aryl, optionally substituted heteroaryl, halogen substituted aryl, boronic acid substituted aryl, boronic ester substituted aryl, boronic esters, boronic acids, optionally substituted fluorene and aryl or hetreoaryl substituted with one or more pendant chains terminated with a functional group, molecule or biomolecule selected from amine, carbamate, carboxylic acid, carboxylate, maleimide, activated esters, N-hydroxysuccinimidyl, hydrazines, hydrazids, hydrazones, azide, alkyne, aldehydes, thiols, and protected groups thereof for conjugation to another substrate, molecule or biomolecule; and wherein at least one of G 1 or G 2 comprises a functional conjugation site for said conjugation; (v) the polymer comprises at least 1 functional group selected from amine, carbamate, carboxylic acid, carboxylate, maleimide, activated esters, N-hydroxysuccinimidyl, hydrazines, hydrazids, hydrazones, azide, alkyne, aldehydes, and thiols within G 1, G 2, L 1 or L 2 that allows, for functional conjugation to another molecule, substrate or biomolecule; (vi) n is an integer from 1 to about 10,000; (vii) a, b, c and d define the mol % of each unit within the structure which each can be evenly or randomly repeated and where a is a mol % from 10 to 100%, b is a mol % from 0 to 90%, and each c and d are mol % from 0 to 25%; and (viii) the G 2, G 1, L 1, L 2, MU and fluorene sub-units, when adjacent, are separated from each other by single bonds. (i) each R is independently a non-ionic side group selected from (CH 2) x (OCH 2 CH 2) y OCH 3 where each x is independently an integer from 0-20, each y is independently an integer from 0 to 50, or a benzyl optionally substituted with one or more halogen, hydroxyl, C 1 -C 12 alkoxy, or (OCH 2 CH 2) z OCH 3 where each z is independently an integer from 0 to 50, capable of imparting solubility in water in excess of 10 mg/mL; (ii) MU is a polymer modifying unit or band gap modifying unit that is selected from the group consisting of a'-k' having the structure: * = site for covalent attachment to unsaturated backbone wherein R is a non-ionic side group capable of imparting solubility in water in excess of 10 mg/mL; (iii) each optional linker L 1 and L 2 are aryl or hetroaryl groups evenly or randomly distributed along the polymer main chain and are substituted with one or more pendant chains terminated with a functional group selected from amine, carbamate, carboxylic acid, carboxylate, maleimide, activated esters, N-hydroxysuccinimidyl, hydrazines, hydrazids, hydrazones, azide, alkyne, aldehydes, thiols, and protected groups thereof for conjugation to another substrate, molecule or biomolecule; (iv) G 1 and G 2 are each independently selected from hydrogen, halogen,alkyne, optionally substituted aryl, optionally substituted heteroaryl, halogen substituted aryl, boronic acid substituted aryl, boronic ester substituted aryl, boronic esters, boronic acids, optionally substituted fluorene and aryl or hetreoaryl substituted with one or more pendant chains terminated with a functional group, molecule or biomolecule selected from amine, carbamate, carboxylic acid, carboxylate, maleimide, activated esters, N-hydroxysuccinimidyl, hydrazines, hydrazids, hydrazones, azide, alkyne, aldehydes, thiols, and protected groups thereof for conjugation to another substrate, molecule or biomolecule; and wherein at least one of G 1 or G 2 comprises a functional conjugation site for said conjugation; (v) the polymer comprises at least 1 functional group selected from amine, carbamate, carboxylic acid, carboxylate, maleimide, activated esters, N-hydroxysuccinimidyl, hydrazines, hydrazids, hydrazones, azide, alkyne, aldehydes, and thiols within G 1, G 2, L 1 or L 2 that allows, for functional conjugation to another molecule, substrate or biomolecule; (vi) n is an integer from 1 to about 10,000; (vii) a, b, c and d define the mol % of each unit within the structure which each can be evenly or randomly repeated and where a is a mol % from 10 to 100%, b is a mol % from 0 to 90%, and each c and d are mol % from 0 to 25%; and (viii) the G 2, G 1, L 1, L 2, MU and fluorene sub-units, when adjacent, are separated from each other by single bonds.