awk '{for (i=1 ;i<=NF;i++){ printf "\"" $i; if ( i==NF) {printf "\","} else {printf "\":"}}; printf "\n" }' awk_file.txt 

 

 cat awk_file.txt 

100001  AAA

100002  AAB

100003  ACA

100004  AdA

100005  AeA

 

awk '{for (i=1 ;i<=NF;i++){ printf "\"" $i; if ( i==NF) {printf "\","} else {printf "\":"}}; printf "\n" }' awk_file.txt 

"100001":"AAA",

"100002":"AAB",

"100003":"ACA",

"100004":"AdA",

"100005":"AeA",