The word keratinizes is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 25
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (40 words)
aeriest, airiest, antsier, arenite, earnest, eastern, entries, inertia, inkiest, intakes, irisate, kainite, karites, keratin, kernite, nastier, nearest, rankest, reknits, restain, restake, retains, retaken, retakes, retinas, seriate, snakier, sneaker, stainer, sterane, stinker, tankers, tinkers, trainee, triaene, trienes, zaniest, zeatins, zestier, zinkier