Characterization and utility of immobilized metal affinity-functionalized cellulose membranes for point-of-care malaria diagnostics

Abstract

Highlights Malaria diagnostics exist at a unique nexus where robustness and usability intersect with a significant need for increased sensitivity. Immobilized metal affinity-functionalized cellulose membranes are a promising tool for increasing the sensitivity of point-of-care malaria diagnostics. For the primary malaria biomarker, histidine-rich protein 2, IMAC membranes were found to increase sensitivity by 15.8-fold compared to traditional methods. IMAC membranes could also be used for capture and recovery of non-histidine rich biomarkers such as Plasmodium lactate dehydrogenase.

Preparation of Polyacrylonitrile-Based Immobilized Copper-Ion Affinity Membranes for Protein Adsorption

“…It utilizes the chelators coupled on solid particles to immobilize the metal ions (as electron-pair acceptors), which could specifically bind with the exposed electron-donating amino acid residues (e.g., histidine, cysteine, tryptophan, etc.) on biomolecule surfaces [ 1 , 2 , 3 , 8 , 9 , 10 , 11 , 12 , 13 ]. The metal ions immobilized on a solid carrier are usually first-row transition metals (Cu 2+ , Ni 2+ , Zn 2+ , Co 2+ , etc.)…”

“…The metal ions immobilized on a solid carrier are usually first-row transition metals (Cu 2+ , Ni 2+ , Zn 2+ , Co 2+ , etc.) [ 5 , 9 , 13 , 14 , 15 , 16 ]. The vacant valence orbitals of a first-row transition metal provide excellent stability for the coordination compound formed.…”

“…Accordingly, the matrix material, spacer arm, chelating agent and the immobilized metal ions of the IMAC or immobilized metal-ion affinity membrane (IMAM) will greatly affect the adsorption effectiveness. As reported in the literature [ 3 , 5 , 12 , 13 , 14 , 15 , 20 , 21 , 22 , 23 , 24 ], the polymeric matrices for IMAMs include cellulose, polyamide, polyvinylbutyral, polysulfone, poly(vinyl alcohol-co-ethylene) and so on. Hydrophilic polymers are more commonly selected; in addition, the polymer functionality for further ligand coupling is also important.…”

“…Prior to metal ion immobilization, the chelating agent needs to be bound to the membrane matrix. The common choices of chelating agents are multidentates, such as iminodiacetic acid, tridentate (IDA), nitrilotriacetic acid, tetradentate (NTA), and N,N,N-tris(carboxymethyl)ethylenediamine, pentadentate (TED) [ 1 , 5 , 13 , 14 , 16 , 32 , 33 ], as well as triazine dyes [ 3 , 5 , 34 , 35 , 36 ]. Nevertheless, the direct coupling of a chelating agent onto a polymeric membrane matrix is not usually easy.…”

“…A better chelating efficiency could be achieved by using IDA and copper ions, according to the literature [ 34 ]. The practical applications of IMAM reported in the literature are broad, such as the purification of commercial human serum albumin (HSA) solution [ 3 ], purification of bovine liver catalase [ 3 ], isolation of lysozyme from egg white [ 12 , 37 ], immunoassay diagnostics [ 13 ], purification of the VP3 protein of infectious bursal disease [ 14 ], simultaneous purification and immobilization of scaffolding protein genes [ 15 ] and purification of a histidine-tagged recombinant protein from Escherichia coli [ 38 ], etc.…”