diff --git a/lib/hd/mnemonic.js b/lib/hd/mnemonic.js
index 165a223c..b8325093 100644
--- a/lib/hd/mnemonic.js
+++ b/lib/hd/mnemonic.js
@@ -121,7 +121,7 @@ Mnemonic.prototype.destroy = function destroy() {
   this.bits = constants.hd.MIN_ENTROPY;
   this.language = 'english';
   if (this.entropy) {
-    this.entropy.fill(0);
+    crypto.cleanse(this.entropy);
     this.entropy = null;
   }
   this.phrase = null;
diff --git a/lib/hd/private.js b/lib/hd/private.js
index 20524cf4..d95a525a 100644
--- a/lib/hd/private.js
+++ b/lib/hd/private.js
@@ -155,14 +155,15 @@ HDPrivateKey.prototype.__defineGetter__('xpubkey', function() {
 
 HDPrivateKey.prototype.destroy = function destroy(pub) {
   this.depth = 0;
-  this.parentFingerPrint.fill(0);
   this.childIndex = 0;
-  this.chainCode.fill(0);
-  this.privateKey.fill(0);
-  this.publicKey.fill(0);
+
+  crypto.cleanse(this.parentFingerPrint);
+  crypto.cleanse(this.chainCode);
+  crypto.cleanse(this.privateKey);
+  crypto.cleanse(this.publicKey);
 
   if (this.fingerPrint) {
-    this.fingerPrint.fill(0);
+    crypto.cleanse(this.fingerPrint);
     this.fingerPrint = null;
   }
 
diff --git a/lib/hd/public.js b/lib/hd/public.js
index b849632a..ac5ef742 100644
--- a/lib/hd/public.js
+++ b/lib/hd/public.js
@@ -118,13 +118,14 @@ HDPublicKey.prototype.__defineGetter__('xpubkey', function() {
 
 HDPublicKey.prototype.destroy = function destroy() {
   this.depth = 0;
-  this.parentFingerPrint.fill(0);
   this.childIndex = 0;
-  this.chainCode.fill(0);
-  this.publicKey.fill(0);
+
+  crypto.cleanse(this.parentFingerPrint);
+  crypto.cleanse(this.chainCode);
+  crypto.cleanse(this.publicKey);
 
   if (this.fingerPrint) {
-    this.fingerPrint.fill(0);
+    crypto.cleanse(this.fingerPrint);
     this.fingerPrint = null;
   }
 
diff --git a/lib/wallet/masterkey.js b/lib/wallet/masterkey.js
index 2157ae25..0ff4c8b6 100644
--- a/lib/wallet/masterkey.js
+++ b/lib/wallet/masterkey.js
@@ -315,7 +315,7 @@ MasterKey.prototype._lock = function lock() {
   }
 
   if (this.aesKey) {
-    this.aesKey.fill(0);
+    crypto.cleanse(this.aesKey);
     this.aesKey = null;
   }
 };
@@ -371,7 +371,7 @@ MasterKey.prototype._decrypt = co(function* decrypt(passphrase, aes) {
   this.ciphertext = null;
 
   if (!aes) {
-    key.fill(0);
+    crypto.cleanse(key);
     return;
   }
 
@@ -423,7 +423,7 @@ MasterKey.prototype._encrypt = co(function* encrypt(passphrase, aes) {
   this.ciphertext = data;
 
   if (!aes) {
-    key.fill(0);
+    crypto.cleanse(key);
     return;
   }
 
diff --git a/lib/wallet/wallet.js b/lib/wallet/wallet.js
index 2b3a857b..f7fb140a 100644
--- a/lib/wallet/wallet.js
+++ b/lib/wallet/wallet.js
@@ -405,12 +405,12 @@ Wallet.prototype._encrypt = co(function* encrypt(passphrase) {
   try {
     yield this.db.encryptKeys(this, key);
   } catch (e) {
-    key.fill(0);
+    crypto.cleanse(key);
     this.drop();
     throw e;
   }
 
-  key.fill(0);
+  crypto.cleanse(key);
 
   this.save();
 
@@ -447,12 +447,12 @@ Wallet.prototype._decrypt = co(function* decrypt(passphrase) {
   try {
     yield this.db.decryptKeys(this, key);
   } catch (e) {
-    key.fill(0);
+    crypto.cleanse(key);
     this.drop();
     throw e;
   }
 
-  key.fill(0);
+  crypto.cleanse(key);
 
   this.save();