Hi Sanju, is the abc data frame created in the below line before using ggplot?
for(ms in names(abc[,-c(1:6)])) 
{ 
  abc <- data.frame(Concentration = abc[,ms], Time = abc$Time, Type = abc$Sample) 
  hello <- ggplot(data = abc, aes(x = Time, y = Concentration, color = Type)) + geom_line(size=1)+ 
}
Convert Concentration = abc[,ms] to Concentration = abc$ms and try.