ResearchSpace :: Browsing by Author "Mthunzi-Kufa, Patience"

Browsing by Author "Mthunzi-Kufa, Patience"

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Applications of microfluidics in biosensing
(2024) Sekhwama, Masindi; Mpofu, Kelvin T; Sivarasu, S; Mthunzi-Kufa, Patience
Microfluidic devices have become a vastly popular technology, particularly because of the advantages they offer over their traditional counterparts. They have such a wide range of uses and can make complex tasks quite efficient. One area of research or work that has benefited greatly from the use of microfluidics is biosensing, where microfluidic chips are integrated into biosensor setups. There are growing numbers of applications of microfluidics in this area as researchers look for efficient ways to tackle disease diagnostics and drug discovery, which are critical in this era of recurring pandemics. In this work, the authors review the integration of microfluidic chips with biosensors, as well as microfluidic applications in biosensing, food security, molecular biology, cell diagnostics, and disease diagnostics, and look at some of the most recent research work in these areas. The work covers a wide range of applications including cellular diagnostics, life science research, agro-food processing, immunological diagnostics, molecular diagnostics, and veterinarian diagnostics. Microfluidics is a field which combines fundamental laws of physics and chemistry to solve miniaturization problems involving fluids at the nanoscale and microscale, and as such, the authors also examine some fundamental mathematical concepts in microfluidics and their applications to biosensing. Microfluidics has relatively new technologies with great potential in terms of applications.
Aptamers and antibodies in optical biosensing
(2025-02) Mpofu, Kelvin T; Chauke, Sipho H; Thwala, Nomcebo L; Mthunzi-Kufa, Patience
Optical biosensing has emerged as a vital tool for real-time, sensitive detection of biological analytes, with aptamers and antibodies leading as key molecular recognition elements. This review examines and compares their distinct roles, advantages, and limitations in optical biosensing. Antibodies, celebrated for their high specificity and mature production protocols, are often preferred in clinical diagnostics. However, challenges like cross-reactivity, environmental sensitivity, and production costs prompt exploration of alternative biorecognition molecules. Aptamers, nucleic acid–based recognition elements, offer several unique advantages, such as ease of synthesis, chemical stability, and amenability to modifications for improved target binding. While their relatively recent discovery means fewer standardized protocols and clinical applications compared to antibodies, aptamers show promise in complex sample matrices and emerging sensor platforms. This review also explores technological advances in both aptamer and antibody integration, surface modification strategies to enhance binding specificity and orientation, and regeneration methods to ensure biosensor reusability. Through a comprehensive comparison, the article aims to identify scenarios where one molecular recognition element holds distinct advantages over the other, paving the way for strategic applications in diagnostics, food safety, and environmental monitoring. In this review, we have explored the advancements and challenges associated with optical biosensing technologies, with a particular focus on LSPR-based sensors. Recent developments in nanoparticle fabrication, hybrid sensor platforms, and external stimulus-responsive systems have opened new avenues for biosensing applications in clinical diagnostics, environmental monitoring, and food safety. The review also discussed the integration of optical biosensors with Raman spectroscopy for enhanced analytical capabilities and highlighted innovations in metamaterial-based sensors for improved sensitivity and specificity. Despite these advances, several challenges remain, including surface stability, reproducibility, and limitations in detecting low-abundance analytes. Addressing these challenges will require further improvements in device design, bioreceptor immobilization strategies, and signal enhancement techniques. Future research efforts should also focus on the development of portable and cost-effective biosensing platforms that can be applied in resource-limited settings. Ultimately, this review provides valuable insights into future trends in aptamer and antibody-based biosensors, encouraging cross-disciplinary collaboration and innovation.
Arduino-based devices in healthcare and environmental monitoring
(2025-04) Tsebesebe, Nkgaphe T; Mpofu, Kelvin T; Sivarasu, S; Mthunzi-Kufa, Patience
Rapid increases in diseases and pandemics over the past years have led to the development of more affordable and accessible biosensing equipment, especially in underdeveloped regions. One of the open-source hardware that has the potential to develop advanced health equipment is the Arduino platform. This review emphasizes the importance of open-source technology, specifically the Atmel family of microcontrollers used in the Arduino development board, and the applications of the Arduino platform in biosensing technologies to advance PoC devices. Furthermore, the review highlights the use of machine learning algorithms to enhance the functionality of user-defined prototypes, aiming to realize PoC devices. It also addresses the successes and limitations of microcontrollers and machine learning in the development of PoC devices using open-source technology. The primary purpose of this paper is to investigate how the Arduino platform can be leveraged to create effective and affordable biosensing solutions, by examining the integration of Arduino with various types of biosensors. The review showcases the potential of Arduino to democratize and innovate biosensor technology. Lastly, this paper extends the investigation of applications of Arduino to general health care and environmental monitoring.
Biocongugation of gold nanoparticles for surface plasmon resonance sensor
(SPIE, 2019-03) Manoto, Sello L; Malabi, Rudzani; Ombinda-Lemboumba, Saturnin; Mthunzi-Kufa, Patience
Over the past few years gold nanoparticle (AuNPs) have become extremely interesting because they possess enhanced optical, electrical and chemical properties. AuNPs have the ability to form robust conjugates with biomolecules such as antibodies and can enhance optical signals making them suitable for a variety of diagnostic applications including the surface plasmon resonance (SPR) technique. SPR is a highly sensitive and label free optical technique which is widely used for detecting biological analytes and analysing the interaction between different types of biomolecules. In this study, bioconjugation was achieved by covalently attaching antibodies to AuNPs and gold coated slides were used as SPR sensor chips in Kretschmann configuration. Several UV/VIS excitation spectra were collected before and after AuNPs were conjugated to antibodies. The results showed that the sensitivity of the SPR system significantly increased because of the bioconjugation of antibodies to AuNPs and this is a promising approach for biosensing applications.
Biology at a single cell level
(2012-10) Mthunzi-Kufa, Patience
In this presentation the author highlights the use of lasers in micro-manipulating single cells and molecules.
Biosensing multidrug-resistant TB genes using SPR
(2024-01) Chauke, Sipho H; Ombinda-Lemboumba, Saturnin; Dube, FS; Mthunzi-Kufa, Patience
Tuberculosis (TB) is one of the most prevalent infectious diseases globally. Although it is curable, several factors, such as the inappropriate use of treatment drugs lead to drug-resistant strains of TB. The burden of infection is disproportionately high in low-income and resource-limited settings. Furthermore, this disparity is exacerbated in patients with already compromised immune systems. Therefore, early detection and treatment of TB play an important role in reducing the spread and progression to drug-resistant disease forms. There are currently a few rapid multi-drug resistant TB diagnostic tests available, however, most are limited due to costs and accessibility. Several genes, such as catalase-peroxidase (katG) and enoyl reductase (inhA) genes, contain mutations that are responsible for resistance to the TB drug, isoniazid. We therefore, aim to use a custom-built surface plasmon resonance (SPR) system to detect katG and inhA genes. Deoxyribonucleic acid (DNA) probes, specific for katG and inhA, were used as biorecognition elements to capture katG and inhA target DNA. The katG and inhA gene-specific DNA probes were immobilized on a gold-coated glass sensor chip before the target DNA was introduced for detection. As a negative control, a mismatched probe, unspecific to both genes was used for confirmation of the absence of the two genes in the experimental setup. The specificity and sensitivity of the capture probes to the target DNA were investigated using the gold-coated glass sensor chip on the SPR setup. The changes in the resonance angle dip indicated the hybridization of the target DNA and the capture probe. The results from this study will contribute to the optimization of an optical-based biosensor detecting drug-resistant mutations.
Characterisation of a Bessel beam optical cell sorting system using microspheres
(SPIE, 2020-02) Lugongolo, Masixole Y; Ombinda-Lemboumba, Saturnin; Manoto, Sello L; Mthunzi-Kufa, Patience
Accurate sorting of specific particles in a mixed population is a desirable capability in the field of biomedical sciences. This enables researchers to purify samples by selecting only the particles of interest. Optical sorting is achieved by using a Bessel beam, which is a non-diffracting, propagation invariant light pattern consisting of concentric rings around a bright central core. This type of beam profile has the ability to employ optical forces in manipulating matter in a sterile environment without physical interaction. The concentric rings enable the simultaneous manipulation of particles of various characteristics in multiple planes due to the different power intensity distributions. Sorting with Bessel beam is an attractive approach using small sample volumes (microliter ranges), which becomes beneficial when working with rare particles of interest and in small samples. In this study a home built Bessel beam optical sorting setup was used to sort polystyrene and silica microspheres of different sizes and refractive indices. Our preliminary results showed that the polystyrene microspheres travelled quicker than the silica type of spheres with the same size due to the high refractive indices. These findings indicate the potential application of sorting different cells with varying refractive indices such as differentiating HIV infected cells from uninfected cells.
Chemical sensor nanotechnology in pharmaceutical drug research
(2022-08) Thobakgale, Setumo L; Ombinda-Lemboumba, Saturnin; Mthunzi-Kufa, Patience
The increase in demand for pharmaceutical treatments due to pandemic-related illnesses has created a need for improved quality control in drug manufacturing. Understanding the physical, biological, and chemical properties of APIs is an important area of health-related research. As such, research into enhanced chemical sensing and analysis of pharmaceutical ingredients (APIs) for drug development, delivery and monitoring has become immensely popular in the nanotechnology space. Nanomaterial-based chemical sensors have been used to detect and analyze APIs related to the treatment of various illnesses pre and post administration. Furthermore, electrical and optical techniques are often coupled with nano-chemical sensors to produce data for various applications which relate to the efficiencies of the APIs. In this review, we focus on the latest nanotechnology applied to probing the chemical and biochemical properties of pharmaceutical drugs, placing specific interest on several types of nanomaterial-based chemical sensors, their characteristics, detection methods, and applications. This study offers insight into the progress in drug development and monitoring research for designing improved quality control methods for pharmaceutical and healthrelated research.
The combination of low level laser therapy and efavirenz drastically reduces HIV infection in TZM-bl cells
(2020-06) Lugongolo, Masixole Y; Manoto, Sello L; Ombinda-Lemboumba, Saturnin; Maaza, M; Mthunzi-Kufa, Patience
Human immunodeficiency virus (HIV) infection remains a global health challenge despite the use of antiretroviral therapy, which has led to a significant decline in the mortality rates. Owing to the unavailability of an effective treatment to completely eradicate the virus, researchers continue to explore new methods. Low level laser therapy (LLLT) has been widely used to treat different medical conditions and involves the exposure of cells or tissues to low levels of red and near infrared light. The study aimed to determine the effect of combining two unrelated therapies on HIV infection in TZM-bl cells.
Comparing amplitude-based and phase-based quantum plasmonic biosensing
(2024) Mpofu, Kelvin T; Mthunzi-Kufa, Patience
The utilization of quantum resources can enhance the sensitivity of conventional measurement techniques beyond the standard quantum limit (SQL). The objective of quantum metrology is to enable such quantum enhancements in practical devices. To achieve this objective, it is essential to have devices that are compatible with existing quantum resources operating within the SQL. Plasmonic sensors are promising candidates among these devices since they are extensively employed in biochemical sensing applications. Plasmonic sensors exhibit a response to slight variations in the local refractive index, which manifests as a shift in their resonance response. This shift, in turn, induces changes in the amplitude and phase of the probing light. By utilizing quantum states of light, such as NOON states, squeezed states, or Fock states, to probe these sensors, the measurement noise floor can be lowered, enabling the detection of signals below the SQL. In this study, we compare two configurations of quantum plasmonic sensing: phase-based and amplitude-based. By considering the Quantum Cram´er Rao bound for both configurations, we demonstrate that the phase-based configuration can more effectively exploit the available quantum resources than the amplitude-based configuration. A limitation of this work is that it did not consider loss.
Could low level laser therapy and highly active antiretroviral therapy lead to complete eradication of HIV-1 in vitro?
(SPIE, 2017-01) Lugongolo, Masixole Y; Manoto, Sello L; Ombinda-Lemboumba, Saturnin; Maaza, M; Mthunzi-Kufa, Patience
Human immunodeficiency virus (HIV-1) infection remains a major health problem despite the use of highly active antiretroviral therapy (HAART), which has greatly reduced mortality rates. Due to the unavailability of an effective vaccine or a treatment that would completely eradicate the virus, the quest for new and combination therapies continues. In this study we explored the influence of Low Level Laser Therapy (LLLT) in HIV-1 infected and uninfected cells. Literature reports LLLT as widely used to treat different medical conditions such as diabetic wounds, sports injuries and others. The technique involves exposure of cells or tissue to low levels of red and near infrared laser light. Both HIV infected and uninfected cells were laser irradiated at a wavelength of 640 nm with fluencies ranging from 2 to 10 J/cm2 and cellular responses were assessed 24 hours post laser treatment. In our studies, laser therapy had no inhibitory effects in HIV-1 uninfected cells as was indicated by the cell morphology and proliferation results. However, laser irradiation enhanced cell apoptosis in HIV-1 infected cells as the laser fluencies increased. This led to further studies in which laser irradiation would be conducted in the presence of HAART to determine whether HAART would minimise the detrimental effects of laser irradiation in infected cells.
Design and FDTD simulation of photonic crystal based sensor for biosensing applications
(SPIE, 2019-03) Manoto, Sello L; Mabena, Chemist M; Malabi, Rudzani; Ombinda-Lemboumba, Saturnin; Mthunzi-Kufa, Patience
Photonic crystals (PhCs) is a unique and flexible class of optical devices that are able to manipulate the electromagnetic fields of light. PhCs is a subwavelength grating structure with a periodic arrangement of a high refractive index layer coated on a low refractive index material and can provide a strong light confinement depending on the size, periodicity and the refractive index. Finite difference time domain (FDTD) method can be used to simulate the electromagnetic properties of light through complex structures such as PhCs, because of the precision of the method in the description of geometry and properties of the material. In this study, FDTD software from Lumerical was used to design and simulate the electromagnetic properties of the PhCs based sensor for biosensing applications. The transmission, reflection and absorption characteristics through the proposed PhCs structure was analysed using a visible wavelength range of 400- 700 nm. The boundary conditions were correctly chosen and consisted of periodic boundary conditions and perfectly matched layers. The results revealed that the transmission and reflectance were dependent on the period of the PhCs and the enhanced electric field was confined in an area allowing for interaction with biological analytes.
Detection and quantification of iodine in biological fluids using photonic-based systems: UV-Vis and Transmission spectroscopy
(2024-01) Mcotshana, Zenande KS; Thwala, Nomcebo L; Ombinda-Lemboumba, Saturnin; Ramokolo, Lesiba R; Lugongolo, Masixole Y; Van Steen, E; Mthunzi-Kufa, Patience
Iodine is a crucial trace element that occurs in minute amounts in nature and is necessary for the development of bones, thyroid function, and several metabolic processes. Iodine deficiency, also known as hypothyroidism, affects millions of individuals worldwide, and an overabundance of iodine in the body is known as hyperthyroidism. The early identification of iodine with high sensitivity and selectivity is crucial for physiological impact since the abnormalities caused by iodine disorder can increase the frequency of mortality and mental impairments. This work aims to detect iodine using UV-Vis and Transmission spectroscopy and utilizing selenium nanoparticles as a probe. Selenium nanoparticles (SeNPs) were synthesized by ND: YAG laser method and characterized by Dynamic light scattering (DLS), and High-resolution transmission electron microscopy (HRTEM), while the conjugation of iodine to SeNPs was confirmed by Ultraviolet-visible (UV-vis) spectroscopy. For iodine detection, UV-Vis and Transmission spectroscopy were used and compared and the synthesized colloidal and spherical selenium nanoparticles were utilized as a probe to detect iodine. The absorption peaks and a red shift for SeNPs changed upon the reaction with iodine and this shift may allow for the estimation of iodine concentration. The two methods will enable the detection and monitoring of iodine at different concentrations in the body thus preventing the onset of iodine-related diseases.
Detection of biological analytes using surface plasmon resonance as a biosensing technique for possible development of a point of care diagnostic tool
(SPIE, 2019-02) Malabi, Rudzani; Manoto, Sello L; Ombinda-Lemboumba, Saturnin; Maaza, Malik; Mthunzi-Kufa, Patience
Surface Plasmon Resonance (SPR) is a very powerful optical sensing technique that detects bimolecular binding interactions and it has turned out to be a suitable platform for clinical analysis. In biological and chemical sensing applications, SPR is used to monitor molecular binding real-time and it also promotes epitope mapping for determining biomolecular structures such as the interactions of proteins, DNA and viruses. This sensing technique also provides sensitive, label free and real-time monitoring of reactions. In this study we have built, characterized and optimized the SPR system for biosensing applications. Spectroscopy and scanning electron microscopy were used to characterize the surface of the SPR biosensor chip functionalized with antibodies. The home-built SPR system was successful in detecting biological analytes thereby paving a way into designing a label-free point-of-care (POC) diagnostic tool.
Detection of mycobacterium tuberculosis using gold nanoparticles conjugated to TB antibodies
(2021-03) Maphanga, Charles P; Manoto, Sello L; Ombinda-Lemboumba, Saturnin; Mthunzi-Kufa, Patience
In recent years, conjugated nanoparticles have gained significant applications in diagnostics, particularly gold nanoparticles (AuNPs). When functionalized with antibodies, AuNPs can selectively interact with cells and biomolecules. The conjugation of biomolecules to AuNPs has been achieved using a variety of techniques, one such approach is the covalent coupling method used in the current study. Generally, in diagnostics, the conjugation of different moieties such as antibodies to the AuNPs widens their applications and provides them with new or enhanced properties. Due to their high specificity and diversity, antibodies are widely used to provide specificity and bioactivity to AuNPs, particularly for biosensor applications. Localized surface plasmon resonance (LSPR) has emerged as a leader among label-free biosensing techniques because it offers sensitive, robust, and rapid detection of biological analytes. Biomolecular adsorptions on AuNPs surface increases the dielectric constant and change the intensities and the wavelengths of the LSPR band associated with AuNPs. As a result, the adsorptions of biomolecules onto surfaces of this AuNPs can be monitored by measuring the absorption spectra of the AuNPs. In this study, TB antibodies were covalently conjugated to AuNPs and used to detect mycolic acid TB antigens at various concentrations. Characterization of the AuNPs was done using transmission electron microscopy (TEM) while the biomolecular interaction between TB antibodies and the antigen was measured using LSPR. From our findings, it was realised that the use of antibodyconjugated AuNPs enhanced the detection of the analyte even at low concentrations of the analyte.
Detection of viral pathogens using optical photonic techniques with the aid of selenium nanoparticles
(2024-01) Mcotshana, Zenande KS; Thwala, Nomcebo L; Ombinda-Lemboumba, Saturnin; Ramokolo, Lesiba R; Thobakgale, Setumo L; Lugongolo, Masixole Y; Van Steen, E; Mthunzi-Kufa, Patience
Viral infections such as HIV and SARS-CoV-2 have significantly increased morbidity in humans and resulted in a significant number of fatalities globally, hence early detection is crucial, particularly at a point-of-care (POC) setting to prevent the spread of these diseases. Localized surface plasmon resonance (LSPR) and green light-based Transmission spectroscopy techniques were used in this study to assess real-time molecular interactions between virus-spiked and non-spiked samples. The current study focuses on integrating selenium nanoparticles (SeNPs) with different optical photonic techniques for enhanced detection of HIV. Selenium nanoparticles were synthesized and functionalized with antibodies specific to HIV. Before and after bioconjugation with viral secondary antibodies, the SeNPs were characterized using Ultraviolet–visible (UV-Vis) spectroscopy, Dynamic light scattering (DLS), High-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy, to elucidate their properties and confirm the presence of functional groups. After that, the NPs were integrated with plasmonic systems and used for the enhanced detection of HIV in comparison to traditional LSPR and Transmission spectroscopy. Colloidal selenium nanoparticles were successfully synthesized, using ND: YAG laser. The orange-colored, spherically shaped nanoparticles were evenly distributed and easily resuspended. Anti-HIV antibodies conjugated to SeNPs were added after HIV-specific antibodies were successfully immobilized on a glass slide substrate to react with HIV pseudovirus. The pseudovirus was effectively identified by the use of Transmission Spectroscopy and LSPR techniques. The two optical techniques for HIV detection were more sensitive after integrating selenium nanoparticles, as compared to the conventional Transmission spectroscopy and LSPR methods. This improved and highly sensitive approach may be utilized to identify viral infections early, thus combating the spread of infectious diseases.
Development of collinear transmission plasmonic biosensor for detection of HIV-1
(SPIE, 2020-02) Ombinda-Lemboumba, Saturnin; Manoto, Sello L; Maphanga, Charles P; Malabi, Rudzani; Mthunzi-Kufa, Patience
Surface Plasmon Resonance (SPR) which is widely used to study interactions between different types of biomolecules, has emerged as a technique of choice for rapid and quantitative analyses. However, there are still some challenges on the use of the classical SPR optical configuration. The prism-based configuration setup requires precise alignment of light onto the sample surface and the oblique reflection angle plane yield optical aberration. In this work we have built, characterized and optimized a simple collinear transmission geometry plasmonic system for the detection of HIV-1. Here, a continuous wave laser at 785 nm with power output of 300 mW was used as light source and a 40X objective lens coupled to a CCD camera was used to collect and detect the transmitted intensity change. Furthermore, a white light source was used to study the wavelength dependency of the sample. We present our findings which may be useful to develop biomedical devices for point-of-care diagnostics and healthcare applications.
Developments in localized surface plasmon resonance
(2024-12) Mcoyi, Michael P; Mpofu, Kelvin T; Sekhwama, Masindi; Mthunzi-Kufa, Patience
Localized surface plasmon resonance (LSPR) is a nanoscale phenomenon associated with noble metal nanostructures that has long been studied and has gained considerable interest in recent years. These resonances produce sharp spectral absorption and scattering peaks, along with strong electromagnetic near-field enhancements. Over the past decade, advancements in the fabrication of noble metal nanostructures have propelled significant developments in various scientific and technological aspects of LSPR. One notable application is the detection of molecular interactions near the nanoparticle surface, observable through shifts in the LSPR spectral peak. This document provides an overview of this sensing strategy. Given the broad and expanding scope of this topic, it is impossible to cover every aspect comprehensively in this review. However, we aim to outline major research efforts within the field and review a diverse array of relevant literature. We will provide a detailed summary of the physical principles underlying LSPR sensing and address some existing inconsistencies in the nomenclature used. Our discussion will primarily focus on LSPR sensors that employ metal nanoparticles, rather than on those utilizing extended, fabricated structures. We will concentrate on sensors where LSPR acts as the primary mode of signal transduction, excluding hybrid strategies like those combining LSPR with fluorescence. Additionally, our examination of biological LSPR sensors will largely pertain to label-free detection methods, rather than those that use metal nanoparticles as labels or as means to enhance the efficacy of a label. In the subsequent section of this review, we delve into the analytical theory underpinning LSPR, exploring its physical origins and its dependency on the material properties of noble metals and the surrounding refractive index. We will discuss the behavior of both spherical and spheroidal particles and elaborate on how the LSPR response varies with particle aspect ratio. Further, we detail the fundamentals of nanoparticle-based LSPR sensing. This includes an exploration of single-particle and ensemble measurements and a comparative analysis of scattering, absorption, and extinction phenomena. The discussion will extend to how these principles are applied in practical sensing scenarios, highlighting the key experimental approaches and measurement techniques.
The effect of low-level laser therapy on severe acute respiratory syndrome coronavirus-2 infected cells
(2024-03) Mngwengwe, Luleka; Lugongolo, Masixole Y; Ombinda-Lemboumba, Saturnin; Ismail, Y; Mthunzi-Kufa, Patience
SARS-CoV-2 is a threat to public health due to its ability to undergo crucial mutations, increasing its infectivity and decreasing the vaccine's effectiveness. There is a need to find and introduce alternative and effective methods of controlling SARS-CoV-2. LLLT treats diseases by exposing cells or tissues to low levels of red and near-infrared light. The study aims to investigate for the first time the impact of LLLT on SARS-CoV-2 infected HEK293/ACE2 cells and compare them to uninfected ones. Cells were irradiated at 640 nm, at different fluences. Subsequently, the effects of laser irradiation on the virus and cells were assessed using biological assays. Irradiated uninfected cells showed no changes in cell viability and cytotoxicity, while there were changes in irradiated infected cells. Furthermore, uninfected irradiated cells showed no luciferase activity while laser irradiation reduced luciferase activity in infected cells. Under SEM, there was a clear difference between the infected and uninfected cells.
The effects of low level laser therapy on both HIV-1 infected and uninfected TZM-bl cells
(Wiley, 2017-01) Lugongolo, Masixole Y; Manoto, Sello L; Ombinda-Lemboumba, Saturnin; Maaza, M; Mthunzi-Kufa, Patience
Human immunodeficiency virus (HIV-1) infection remains a major health problem despite the use of highly active antiretroviral therapy (HAART), which has greatly reduced mortality rates. Due to the unavailability of an effective vaccine and treatment that would completely eradicate the virus in infected individuals, the quest for new therapies continues. Low level laser therapy (LLLT) involves the exposure of cells to low levels of red or infrared light. LLLT has been widely used in different medical conditions, but not in HIV-1 infection. This study aimed to determine the effects of LLLT on HIV-1 infected and uninfected TZM-bl cells. Both infected and uninfected cells were irradiated at a wavelength of 660 nm with different fluences from 2 J/cm2 to 10 J/cm2 . Changes in cellular responses were assessed using cell morphology, viability, proliferation, cytotoxicity and luciferase activity assays. Upon data analysis, uninfected irradiated cells showed no changes in cell morphology, viability, proliferation and cytotoxicity, while the infected irradiated cells did. In addition, laser irradiation reduced luciferase activity in infected cells. Finally, laser irradiation had no inhibitory effect in uninfected cells, whereas it induced cell damage in a dose dependent manner in infected cells.

Browsing by Author "Mthunzi-Kufa, Patience"

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