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Isolation and characterisation of phage-displayed scFv antibodies targeting PfHSP70 and PfLDH of plasmodium falciparum

(2026-07) Gasa, NL; Zuma, LK; Chiliza, TE; Kwezi, Lusisizwe; Luthuli, SD; Pooe, OJ

Plasmodium falciparum is the most virulent human malaria parasite and is responsible for numerous deaths annually. The increasing resistance of P. falciparum to antimalarial drugs necessitates the development of improved diagnostic tools for timely malaria detection. Malaria biomarkers such as PfHSP70 and PfLDH are highly valuable for malaria detection because they are essential for parasite survival and are consistently expressed during infection. PfHSP70 is associated with the parasite’s stress adaptation and proteostasis mechanisms under febrile and drug-induced conditions, while PfLDH plays a central role in glycolytic metabolism and redox balance. Their functional importance, parasite specificity and elevated expression during active infection make these proteins reliable molecular indicators for the sensitive and specific detection of P. falciparum, thereby supporting their potential application in rapid diagnostic and biosensing platforms for malaria surveillance and disease management. In this study, an M13 phage-displayed single-chain variable fragment (scFv) antibody library was used to screen for antibodies against recombinant PfHSP70 and PfLDH. Four rounds of biopanning were conducted to enrich high-affinity binders, followed by ELISA, UV-visible spectroscopy and microscale thermophoresis (MST) to evaluate specificity and binding affinity. Functional interactions were assessed in Escherichia coli expressing PfHSP70 or PfLDH. Recombinant PfHSP70 and PfLDH were successfully expressed and purified from E. coli, with approximately 50% of selected colonies demonstrating significant binding to both targets, confirming the enrichment of antigen-specific phages. Specific phages were validated using ELISA and transmission electron microscopy (TEM). Selected scFvs exhibited strong target binding, with MST-determined dissociation constants (Kd) of 7.47 μM for PfHSP70 and 3.64 μM for PfLDH. Exposure to scFv-displaying phages impaired the survival of PfHSP70- and PfLDH-expressing E. coli and induced spectral shifts consistent with protein–antibody interactions. This study validates phage display as a robust platform for isolating high-affinity scFvs against P. falciparum targets. These binders have the potential to develop into low-cost diagnostic tools, addressing the urgent need for novel diagnostic interventions. Nevertheless, further studies are required to confirm binding specificity and assess translational applicability.

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Practical deployment of a private NB-IoT network with open-source platforms

(2026-08) Makhalanyane, Thapelo; Hlabishi, Kobo I

Narrowband Internet of Things (NB-IoT) has emerged as a Low Power Wide Area Network (LPWAN) technology for industrial and enterprise IoT applications, offering licensed spectrum operation with guaranteed Quality of Service (QoS). This work presents a comprehensive, step-by-step guide to deploying a private NB-IoT network using open-source platforms. Existing literature on open-source NBIoT implementations is reviewed, and candidate platforms, including OpenAirInterface (OAI) and srsRAN, are evaluated against commercial solutions. A suitable open-source NB-IoT prototyping platform is then selected based on its demonstrated compatibility with commercial offthe-shelf (COTS) user equipment and robust support for 3GPP Release 13/14 features. The complete system architecture is detailed, including the eNodeB implementation on USRP B210 software-defined radio hardware and its integration with a lightweight Evolved Packet Core (EPC) optimised for IoT applications. A comprehensive testing methodology is employed to progressively validate the system, from basic signal generation and synchronisation through broadcast channels and random access procedures to end-to-end data connectivity. Experimental results using commercial off-the-shelf equipment demonstrate successful deployment, achieving a measured uplink throughput of 11 kbps, a downlink throughput of 17 kbps, and latency ranging from 300 ms to 15 s, depending on signal conditions. This work provides researchers and practitioners with a fully reproducible framework for establishing cost-effective private NB-IoT networks suitable for industrial automation, smart agriculture, environmental monitoring, and enterprise IoT deployments.

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Dry sliding wear behaviour of laser cladded altisicrco high entropy alloy coatings on Ti6Al4V: influence of CR/CO and AL/TI enrichment

(2026-08) Raselabe, KM; Makhatha, ME; Makoana, Nkutwane W; Skhosane, Besabakhe S

This study investigated how compositional variation within the AlTiSiCrCo high-entropy alloy (HEA) system affects the microstructure, hardness, and dry sliding wear behaviour of laser-cladded coatings on Ti6Al4V. Three coatings, namely, equiatomic (HEA 1), Cr/Co-enriched (HEA 2), and Al/Ti-enriched (HEA 3), were characterized by SEM, EDS, XRD, and Vickers microhardness and tested for dry sliding wear using a ball-on-disc tribometer at 5 N and 15 N. All coatings comprise a BCC solid solution matrix reinforced by intermetallic precipitates. HEA 2 and HEA 3 gave the highest hardness (755 HV and 754 HV, respectively) against 705 HV for HEA 1 and 345 HV for the Ti6Al4V substrate. All HEA coatings reduced wear rate relative to Ti6Al4V; HEA 2 recorded the lowest rate (4.570×10−5 mm3/N.m and 2.744×10−4 mm3/N.m at 5 N and 15 N, respectively), well below the substrate (2.257×10−4 mm3/N.m and 0.0014 mm3/N.m at 5 N and 15 N, respectively). Worn surface analysis showed abrasive/delamination at 5 N transitioning to more severe abrasive, adhesive, and delamination wear at 15 N. The enhanced wear resistance of HEA 2 stems from the BCC solid solution strengthening, intermetallic reinforcement, and high chromium content, which aids in the formation of the Cr2O3 protective oxide film. Overall, enriching the coating with chromium and cobalt proved to be the most effective approach for improving the tribological performance of laser-cladded AlTiSiCrCo HEA coatings on Ti6Al4V.

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Assessing institutional readiness for implementing the National Language Policy Framework for public higher education institutions in South Africa

(2026-06) RavyseI, N; Van Dyk, T; Wilken, Ilana; Du Plessis, D

This article investigates the institutional readiness of South African public higher education institutions for the implementation of multilingual language policies, specifically focusing on the recently promulgated National Language Policy Framework for Public Higher Education Institutions (NLPFPHE). Drawing on applied linguistics, Weiner’s (2009) theory of organisational readiness for change, and policy implementation studies, the authors explore how various institutional factors shape the capacity to implement language policies effectively. Using a mixedmethods approach, data from the national language audit (Van Dyk, Wilken, Ravyse, Du Plessis, Khumalo and Steyn, 2023) to assess current preparedness is analysed. The findings highlight key areas where institutions demonstrate readiness, such as staff engagement with policy, but also expose critical gaps in resources and student awareness. Moreover, the authors advocate for applying organisational readiness theory as a framework for guiding language policy implementation without specific models from the Department of Higher Education and Training (DHET). By outlining challenges and opportunities in the current landscape, this article offers practical insights for institutions that foster linguistic inclusivity and excellence. It aims to empower stakeholders with a structured approach to assess readiness, address gaps, and enhance the implementation of multilingual language policies.

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Quantum biosensing illuminates infected cells for timely disease diagnosis

(2026) Mthunzi-Kufa, Patience; Mpofu, Kelvin T

Photonics has a profound impact on daily life in numerous ways, from communication and entertainment to manufacturing and healthcare. In Africa, photonics applications in point-ofcare diagnostics, the diagnosis of substandard drugs, and treatments for cancer, diabetic wounds, and other ailments promise significant improvements in healthcare and the quality of human life. Of particular interest is that quantum technologies can be used for new forms of sensing, imaging, and computing, with potential applications in diagnostics and drug discovery. The amalgamation of biological molecules, such as deoxyribonucleic acid (DNA), proteins, or enzymes, with quantum sensors (QS), which illuminate changes in light emissions during lightmatter interactions, introduces a game-changer in rapid, sensitive, and specific disease diagnostics. Here, we theoretically demonstrate how the integration of quantum phenomena into sensing mechanisms could enable the detection of minute variations in intracellular factors, such as refractive index, cell morphology, and pH shifts in infected versus uninfected cells. We propose a conceptually designed quantum biosensing experiment that can be conducted using nitrogen vacancy (NV) centres.