Abstract: Chlorotoxin derivatives containing amino acid sequence X0X1CMPCXS1XS2XS3DHXS4XS5ARRCX2X3CCGGYGX4CFGYQC LCX5X6X7X8 wherein (i) the N-terminal X0X1 cluster is AM, 0M, or 00; (ii) the solubility XS1XS2XS3XS4XS5 cluster is FTTQT, FTTES, SSSQT, SSSES, FSSQT, FSSES, or FSSQS; (iii) the internal X2X3X4 cluster is DKR, RDK, KDR, IKY, HKW, DRK, LKQ, KKK; and (iv) the C-terminal X5X6X7X8 cluster is N000, R000, NR00, NRG0, NRGY, NRRR, or RRRR; 0 denotes a position where no amino acid is present; the chlorotoxin derivative has a relative human MMP-2 binding that is at least 1.62 times higher than the wild-type chlorotoxin of SEQ ID NO: 1.