Malaysian Journal of Analytical Sciences Vol 20 No 4 (2016): 735 - 740

DOI: http://dx.doi.org/10.17576/mjas-2016-2004-05

 

 

 

SPECTROSCOPIC CHARACTERIZATION OF COPPER(II)-BASED TETRAPEPTIDES

 

(Pencirian Spektroskopik Kuprum(II) Tetrapeptida)

 

Mohd. Basyaruddin Abdul Rahman^1,2*, Sharifa Zaithun Begum¹, Mohamed Ibrahim Mohamed Tahir²,

Haslina Ahmad^1,2, Emilia Abdul Malek^1,2

 

¹Enzyme and Microbial Technology Research

²Department of Chemistry, Faculty of Science

Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia

 

*Corresponding author: basya@upm.edu.my

 

 

Received: 17 August 2015; Accepted: 7 May 2016

 

 

Abstract

Five different histidine and aspartic acid based tetrapeptides were designed using LOMETS and PyMol. They were chemically synthesized following the solid phase Fmoc-peptide synthesis protocols and were analysed using the reverse-phase High Performance Liquid Chromatography (HPLC) C₁₈ analytical column for the purity. The peptides were further analysed by Liquid Chromatography Mass Spectrometry (LCMS) to see if the desired peptides were synthesized systematically. Copper(II) acetate monohydrate was bound to the peptides and the best molar ratio for the binding of these metal salts to peptides was 2:1. These observations were monitored through several spectroscopic techniques. The first physical observations for the successful synthesis of metallopeptides were the colour change, the melting/decomposition points and the solubility of these metallopeptides. Due to the visible colour change of the peptides to metallopeptides, UV-Visible spectroscopy and UV-Fluorescence spectroscopy were used as a qualitative analysis tests and the results were in agreement with other researchers’ data from similar researches.

 

Keywords: copper(II), histidine, aspartic acid, tetrapeptides, spectroscopic

 

Abstrak

Lima tetrapeptida berbeza yang mempunyai histidine dan asid aspartik direkabentuk oleh LOMETS dan PyMol. Tetrapeptida ini disintesis mengikut skim fasa pepejal peptida dan dianalisis menggunakan fasa sonsang Kromatografi Cecair Berprestasi Tinggi (HPLC) C₁₈ turus analisis untuk mengetahui keaslian peptida. Kesemua peptida ini dianalisis mengunakan Kromatografi Cecair-Spektrometer Jisim (LC-MS) untuk mengkaji sintesis peptida secara sistematik. Kuprum(II) asetat monohidrat terikat kepada peptida dan nisbah mol yang terbaik untuk mengikat garam logam ini kepada peptida adalah 2:1. Cerapan ini telah dipantau melalui beberapa teknik spektroskopi. Pemerhatian fizikal pertama untuk logam peptida yang berjaya disintesis ialah perubahan warna, takat lebur/penguraian dan kebolehlarutan peptida logam ini. Oleh kerana perubahan warna yang nyata dalam dari peptida kepada logam peptida, spektroskopi Ultralembayung-tampak (UV-Vis) dan spektroskopi Ultralembayung-Pendafluor (UV-Fluorescence) digunakan sebagai ujian analisis kuantatif dan data yang diperolehi adalah setara dengan perolehan data bagi penyelidikan yang serupa.

 

 Kata kunci: Kuprum(II), histidin, asid aspartik, tetrapeptida, spektroskopi

 

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