APOSTROPHE Insertion Error in DB2

Hi ,
I am getting error while inserting a comments.
My table description is :
CREATE TABLE TEST1.EMP
(
NAME VARCHAR(20),
COMMENT VARCHAR(255)
) IN TESTDB.TESTTSP;

Now iam trying to insert a record like below

INSERT INTO TEST1.EMP (NAME,COMMENT) VALUES ('JOHN','Validate  JOHN'S Details')
 
DB21034E  The command was processed as an SQL statement because it was not a
valid Command Line Processor command.  During SQL processing it returned:
SQL0104N  An unexpected token "S" was found following "".  Expected tokens may
include:  "MICROSECONDS MICROSECOND SECONDS SECOND MINUTES MINUTE HOURS".  
SQLSTATE=42601

kindly help me how to insert this record

I also tested like below

INSERT INTO TEST1.EMP (NAME,COMMENT) VALUES ('JOHN',"Validate  JOHN'S Details")

SQL0206N  "Validate  JOHN'S Details" is not valid in the context where it is used.