The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.

The peptide A9 has been reported in the literature to exhibit high affinity and specificity towards the HER2 receptor. In our previous report, we observed the retro variant of A9 peptide, rL-A9, to be a promising molecule for targeting HER2-expressing breast cancer cells. The present study, thus aimed at designing and synthesis of a peptide-drug conjugate by linking the rL-A9 peptide with DOX. A linker, N-succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) was utilized for conjugation of DOX at one end and the peptide at the other end. The N-hydroxysuccinimidyl ester group of SMCC was conjugated with the amine (-NH2) group of DOX resulting in the formation of amide bond. The thiol (-SH) functionality was introduced by coupling cysteine amino acid at the N-terminus of the rL-A9 peptide for covalent linkage with the maleimide group of SMCC. Successful synthesis of the conjugate was confirmed by MALDI-TOF mass spectrometry. Cytotoxicity, cellular uptake and internalization of the peptide, drug and peptide-drug conjugate were assessed in SKOV3 cells using flow cytometry and confocal fluorescence microscopy.