Convert String of JSON format to JSON Object to PHP

I got this i think a string of data

{ "_id" : ObjectId( "54c527176c69ae1029000029" ), "id" : "5289d4f33cc66", "gid" : "rm_ascorbic_acid_10", "global_id" : "rm_ascorbic_acid_10-5289d4f33cc66", "title" : "Ascorbic Acid", "short_description" : "", "description" : "It is used to prevent and treat deficiencies of vitamins B1, B6 and B12; as an adjunct in the management of neuromuscular pain responsive to vitamins B1, B6", "category" : [ { "category_id" : "1", "category_name" : "appetite stimulants" } ], "prescription" : "0", "status" : "1", "shipping_id" : "5289d4ce76dac", "inventory" : "530f4a1e8f179", "images" : [ { "name" : "1384764589-0-0-RM_Ascorbic_Acid_10", "mime" : "image/jpeg", "size" : 27556, "uuid" : "270a174ca8d76405e096575bc23cf420", "extension" : "jpg", "date" : Date( 1384764659000 ) } ], "qty" : 100, "wholesale_price" : 100, "srp" : 110, "qty_label" : "", "dimension" : { "weight" : "    kg", "height" : "", "length" : "", "width" : "" }, "attribute" : [], "created" : Date( 1384764659000 ), "updated" : Date( 1385001875000 ) }

and i want this to convert on a array or json format.. When i use explode, i dont get the data that i want cause it also splits the other data.

thanks in advance...