SQL query to remove 'Â' from DB

New characters got injected into my wp-posts table. I was able to remove all except  who is quite adamant to stay. this is the query i used:
UPDATE wp_posts SET post_content = REPLACE(post_content, 'Â', '');
guess its a silly mistake. my sql skills are below novice levels.
please advice.

background:
just in case you need to know, i made changes to my old wp-config file for enabling multisite. i did NOT specify DB_CHARSET and DB_COLLATE in it, which wasnt present earlier either. but still the encoding got messed up somehow. i ran this bunch of code and all of the strange characters got removed, except  ofcourse:

UPDATE wp_posts SET post_content = REPLACE(post_content, '“', '“');
UPDATE wp_posts SET post_content = REPLACE(post_content, '”', '”');
UPDATE wp_posts SET post_content = REPLACE(post_content, '’', '’');
UPDATE wp_posts SET post_content = REPLACE(post_content, '‘', '‘');
UPDATE wp_posts SET post_content = REPLACE(post_content, '—', '–');
UPDATE wp_posts SET post_content = REPLACE(post_content, '–', '—');
UPDATE wp_posts SET post_content = REPLACE(post_content, '•', '-');
UPDATE wp_posts SET post_content = REPLACE(post_content, '…', '…');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '“', '“');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '”', '”');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '’', '’');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '‘', '‘');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '—', '–');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '–', '—');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '•', '-');
UPDATE wp_comments SET comment_content = REPLACE(comment_content, '…', '…');