By Louis Navellier of
InvestorPlace Penny stock investments in the biotech sector abound right now after the recent market turmoil this summer. Healthcare and biotech penny stocks can be volatile, particularly those drug manufacturers that are not yet profitable and are waiting on an important FDA approval notice. But these stocks can be very good investments if you buy at the right time. My quantitative screens show that a number of biotech penny stocks -- that is, cheap healthcare companies trading for less than $3 a share -- have big upside potential for September as volume picks up on Wall Street. Here are nine top penny stocks in the biotech sector to consider.