This study presents LHRH conjugated drug delivery via a magnetite nanoparticle-modified microporous Poly-Di-Methyl-Siloxane (PDMS) system for the targeted suppression of triple-negative breast cancer cells. First, the MNP-modified PDMS devices are fabricated before loading with targeted and untargeted cancer drugs. The release kinetics from the devices are then studied before fitting the results to the Korsmeyer–Peppas model. Cell viability and cytotoxicity assessments are then presented using results from the Alamar blue assay. Apoptosis induction is then elucidated using flow cytometry. The in vitro drug release studies demonstrated a sustained and controlled release of unconjugated drugs (Prodigiosin and paclitaxel) and conjugated drugs [LHRH conjugated paclitaxel (PTX+LHRH) and LHRH-conjugated prodigiosin (PG+LHRH)] from the magnetite nanoparticle modified microporous PDMS devices for 30 days at 37 °C, 41 °C, and 44 °C. At 24, 48, 72, and 96 h, the groups loaded with conjugated drugs (PG+LHRH and PTX+LHRH) had a significantly higher (p < 0.05) percentage cell growth inhibition than the groups loaded with unconjugated drugs (PG and PTX). Additionally, throughout the study, the MNP+PDMS (without drug) group exhibited a steady rise in the percentage of cell growth inhibition. The flow cytometry results revealed a high incidence of early and late-stage apoptosis. The implications of the results are discussed for the development of biomedical devices for the localized and targeted release of cancer drugs that can prevent cancer recurrence following tumor resection.

The need for growth in Africa's manufacturing ecosystem was highlighted by the COVID-19 pandemic as personal protective equipment (PPE) had to largely be imported. This paper presents the design, fabrication and testing of a face shield produced using locally available materials and methods in Ghana. User research with medical professionals and other PPE users revealed issues with existing commercial face shields such as high cost, poor durability, and discomfort. An improved face shield design was developed, leveraging fabrication methods employed by local tailors. An elastic/foam band made from African fabric was integrated with a plastic sheet, the former being reusable and the latter being disposable. A series of flow visualization experiments were used to determine the efficacy of this shield against that of the commercial counterpart. Particle count and velocity flow field results revealed superior performance of the local design in terms of particle blocking. This study underscores the potential for decentralized manufacturing in Africa, providing a model for creating effective, affordable and accessible PPE using indigenous resources and simple production techniques.

In this paper, the rapid evolution of a cluster of complementary technologies that have underpinned additive manufacturing is reviewed. Enabling technologies - 3D Scanning, 3D modeling, and 3D printing technologies - that have been revolutionary in bringing additive manufacturing to mainstream have also been discussed. Conventional engineering processes and its limitations are explored. Targeted applications of additive manufacturing across the depth and breadth of engineering with concrete examples: healthcare, automotive, aerospace, etc., are highlighted. The opportunities that additive manufacturing offers the nascent Africa technological landscape, and her industrialization aspirations are contextually examined and implications as such for leapfrogging as well as the opportunities for employment for its teeming youth are emphasized. Keyword: Additive Manufacturing; 3D modelling, 3D scanning, smart manufacturing Aims Research Journal Reference Format: McBagonluri, F., Klenam, D.E.P., Agyepong, L., Osei, E.D., Mornah, D, & Danyuo, Y. (2022): Additive Manufacturing: A Paradigm Shift For Industrialization In Africa . Advances in Multidisciplinary and Scientific Research. Vol. 9. No. 1, Pp 1–22. www.isteams.net/aimsjournal. dx.doi.org/10.22624/AIMS/V9N1P1

Illegal mining and improper waste disposal have led to the contamination of water bodies in Ghana, making it difficult for communities to obtain safe drinking water. Rural areas are particularly affected due to the lack of decentralized water supply systems. A water filtration system is modeled and fabricated to address the issue. The system consisted of ceramic filtration units for dirt and particulate removal, activated carbon for particle adsorption, processed orange peels for heavy metal adsorption, and a porous polydimethylsiloxane membrane to prevent leaked particles from passing through the filtration track. Optimizations of the filtration system were done to reduce turbidity and levels of heavy metals in polluted water samples. The filtration system reduced the presence of lead by 34%, copper by 98.45%, cadmium by 80.95%, and zinc by 83.33% in the water samples. The filtration system also effectively removed suspended particulates from contaminated water samples. Implications of the result were discussed for the potential use of a multipurpose water filtration system for heavy metal removal and particulate adsorption using agricultural waste materials.

This article presents silica nanoparticles for the sustained release of AMACR antibody-conjugated and free doxorubicin (DOX) for the inhibition of prostate cancer cell growth. Inorganic MCM-41 silica nanoparticles were synthesized, functionalized with phenylboronic acid groups (MCM-B), and capped with dextran (MCM-B-D). The nanoparticles were then characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, zeta potential analysis, nitrogen sorption, X-ray diffraction, and thermogravimetric analysis, before exploring their potential for drug loading and controlled drug release. This was done using a model prostate cancer drug, DOX, and a targeted prostate cancer drug, α-Methyl Acyl-CoA racemase (AMACR) antibody-conjugated DOX, which attaches specifically to AMACR proteins that are overexpressed on the surfaces of prostate cancer cells. The kinetics of sustained drug release over 30 days was then studied using zeroth order, first order, second order, Higuchi, and the Korsmeyer-Peppas models, while the thermodynamics of drug release was elucidated by determining the entropy and enthalpy changes. The flux of the released DOX was also simulated using the COMSOL Multiphysics software package. Generally, the AMACR antibody-conjugated DOX drug-loaded nanoparticles were more effective than the free DOX drug-loaded formulations in inhibiting the growth of prostate cancer cells in vitro over a 96 h period. The implications of the results are then discussed for the development of drug-eluting structures for the localized and targeted treatment of prostate cancer.

Surface modification of poly-dimethyl-siloxane (PDMS) with biopolymers enhances surface wettability. Surface modifications of PDMS-based substrates was done via spin-coating polyethylene-glycol (PEG), poly(lactide-co-glycolic acid) (PLGA), and sodium alginate (SA) at 4000 revs. per. min under vacuum. Samples were characterized using a scanning electron microscope. Substrate wettability was characterized using contact angle measurements approach. Cell-surface attachment was demonstrated by growing MCF-10A Cells. Coated PDMS-based substrates with SA had a contact angle of 12° showing a high degree of hydrophilicity and wettability. Similarly, substrates coated with PEG reported a contact angle of 25°, while PLGA recorded 42.2°. It was also observed that pre-straining the PDMS/PDMS-Fe 3 O 4 substrates before spin-coating could significantly reduce the contact angle to about 8.5° and hence improve surface wettability. The result was discussed for potential PDMS implant integration into the body. Graphical abstract

This article presents the release kinetics (RK) of a fungicidal antimicrobial agent (AMA), potassium sorbate (PS), that prolongs the shelf life of packaged food. The effects of PS release are explored on peanut and fresh bread to determine the effects of PS on Aspergillus niger (AN) microbe growth. The AN was cultured in a potato dextrose agar (PDA) medium to obtain AMA activity on the film. AMA activity of PS incorporated into cellulose acetate (CA) based film was tested on peanuts and fresh bread for an extended period of time. The RK of PS from the films was obtained by studying the de-swelling properties of PS loaded film at room temperature (24 degrees C) and at elevated temperature (37 degrees C). The diffusion coefficients of PS released through the film network were obtained to be between 8.32 x 10(-10) to 7.3 x 10(-7) m(2)/s. The release exponents (n) of PS from the film occurred by anomalous transport with n-values ranging from 0.13 to 0.16 at 24 degrees C and 0.5 to 0.89 at 37 degrees C. The average flux released from the CA film was consistent with the percentage PS release from the CA film showing that modeling the effective diffusion of PS from a porous media is feasible. The released PS was potent enough to inhibit the growth of AN for a week then over a period of 2 years. Thereafter, the implications of the results in designing smart food packaging for enhanced food preservation were discussed.

This paper presents in vitro studies of the sustained release of Annona muricata leaf extracts (AME) from hybrid electrospun fibers for breast cancer treatment. Electrospun hybrid scaffolds were fabricated from crude AME extracts, poly(lactic-co-glycolic acid)/gelatin (PLGA/Ge) and pluronic F127. The physicochemical properties of the AME extract and scaffolds were studied. The antiproliferative effects of the scaffolds were also assessed on breast cancer (MCF-7 and MDA-MB-231) and non-tumorigenic breast (MCF10A) cell lines. Scanning electron microscope micrographs revealed a random network of micro- and submicron fibers. In vitro drug release profiles, governed by quasi-Fickian diffusion at pH 7.4 and non-Fickian super case II at pH 6.7, showed initial burst AME release from the PLGA/Ge-AME and PLGA/Ge-F127/AME fibers at pH 7.4, and burst release from PLGA/Ge-F127/AME (not observed from PLGA/Ge-AME) at pH 6.7. Then, a slower, sustained release of the remaining AME from the fibers, attributed to the onset of degradation of the PLGA/Ge backbone, was observed for the next 72 hr. The cumulative release of AME was 89.33 ± 0.73% (PLGA/Ge-AME) and 51.17 ± 7.96% (PLGA/Ge-F127/AME) at pH 7.4, and 9.27 ± 2.3% and 73.5 ± 4.5%, respectively, at pH 6.7. Pluronic F127 addition increased the drug loading capacity and prolonged the sustained AME release from the fibers. The released AME significantly inhibited the in vitro growth of the breast cancer cells more than the non-tumorigenic cells, due to the induction of apoptosis, providing evidence for using pluronic F127-containing electrospun fibers for sustained and localized AME delivery to breast cancer cells.

This article presents the results of cell-surface interactions on polydimethylsiloxane (PDMS)-based substrates coated with nanoscale gold (Au) thin films. The surfaces of PDMS and PDMS-magnetite (MNP)-based substrates were treated with UV-ozone, prior to thermal vapor deposition (sputter-coated) of thin films of titanium (Ti) onto the substrates to improve the adhesion of Au coatings. The thin layer of Ti was thermally evaporated to improve interfacial adhesion, which was enhanced by a 40-nm thick film microwrinkled/buckled wavy layer of Au, that was coated to enhance cell-surface interactions and protein absorption. Cell-surface interactions were studied on the hybrid surfaces using a combination of optical and fluorescence microscopy. Consequently, cell proliferation and surface cytotoxicity (of the sputter-coated PDMS surfaces) were elucidated by characterizing the metabolic activity in the presence of breast cancer and normal breast cells. The photothermal conversion efficiency associated with laser-materials interactions with the PDMS/PDMS-magnetite-based composites was shown to have an optimum efficiency of ~31.8%. The implications of the results are discussed for potential applications of PDMS nanocomposites in implantable biomedical devices.

Hybrid composite nanofibers, with the potential to enhance cell adhesion while improving sustained drug release profiles, were fabricated by the blend electrospinning of poly(d,l-lactic-co-glycolic acid) (PLGA), gelatin, pluronic F127 and prodigiosin (PG). Scanning Electron Microscopy (SEM) images of the nanofibers revealed diameters of 1.031 ± 0.851 μm and 1.349 ± 1.264 μm, corresponding to PLGA/Ge-PG and PLGA/Ge-F127/Ge, respectively. The Young's moduli were also determined to be 1.446 ± 0.496 kPa and 1.290 ± 0.617 kPa, while the ultimate tensile strengths were 0.440 ± 0.117 kPa and 0.185 ± 0.480 kPa for PLGA/Ge-PG and PLGA/Ge-F127/Ge, respectively. In-vitro drug release profiles showed initial (burst) release for a period of 1 h to be 26.000 ± 0.004% and 16.000 ± 0.015% for PLGA/Ge and PLGA/Ge-F127 nanofibers, respectively. This was followed by 12 h of sustained release, and subsequent slow sustained release of PG from the composite nanofibers. The cumulative release of PG (for three days) was determined to be 82.0 ± 0.1% for PLGA/Ge and 49.7 ± 0.1% for PLGA/Ge-F127 nanofibers. The release exponents (n) show that both nanofibers exhibit diffusion-controlled release by non-Fickian (zeroth order) and quasi-Fickian diffusion in the initial and sustained release regimes, respectively. The suitability of the composite nanofibers for supporting cell proliferation and viability, as well as improving sustained release of the drug were explored. The in-vitro effects of cancer drug (PG) release were also studied on breast cancer cell lines (MCF-7 and MDA-MB-231 cells). The implications of the results are discussed for the potential applications of drug-nanofiber scaffolds as capsules for localized delivery of chemotherapeutic drugs for the treatment of triple negative breast cancer.

This paper presents the characterization of laterite-cement-based matrix composites, reinforced with chemically modified bamboo fibers. Fiber extraction and chemical modification were first explored by soaking slabs of bamboos in NaOH solution (5 wt.% of NaOH in distilled water) for 14 days. Fiber characterization, as well as the flexural and compressive strength of reinforced composites, were carried out with MTS universal mechanical testing machine. Comparative results on the compressive and flexural strength were obtained at 80 wt.% laterite (L) to 20 wt.% cement (C) with fiber ratios from 5-25 wt%. The compressive strength of the composites varied from 7.2 MPa (at 5 wt.% bamboo fiber) to 17.67 MPa (at 25 wt% fiber blocks). The hardness of the composites was found to improve from 66.67-75.0 HD with bamboo fibers. Results were then discussed for possible structural applications such as enhancing low-cost building blocks for rural communities in Ghana.

This paper presents a recent study on recycling poly-ethylene-tetraphylate (PET), known as plastic waste material in Ghana, to wealth. Composites were produced by heating aggregates together with shredded PET plastic waste material, while bitumen was added to the plastic-coated aggregates. The composites produced were reinforced with 4.5 wt%, 9.0 wt%, 13.6 wt%, and 18.0 wt% PET. Mechanical properties of the fabricated composite samples were studied with a Universal testing machine for optimization. The work demonstrated that shredded PET plastic waste material acts as a strong binding agent for bitumen that can improve on the shelf life of the asphalt. From the results, 13.6 wt% concentration of PET was shown to experience the maximum compressive strength and flexural strength. Besides, water resistance was shown to increase with PET concentrations/weight fraction. From the data characterized 13.6 wt% of PET plastic gives the optimum plastic concentration that enhances the rheological properties of bitumen. The implications of the result are therefore discussed for the use of 13.6 wt% PET in road construction.

Titanium alloys have been extensively used in biomedical applications owing to its low density, excellent biocompatibility (i.e., biological and chemical inertness), and unique mechanical properties. However, there is a high disparity between Young's moduli of the implant and the natural bone. This disparity causes stress shielding in the body. This paper presents the effect of particle size and sintering time of Ti–6Al–4V powder used in the formation of a porous implant, sintered at 980 °C. Morphological characteristics of the sintered samples were obtained with a scanning electron microscope. The effect of surface hydrophilicity of the samples was elucidated via surface wettability testing using contact angle measurement with bio-fluid. Mechanical characterization was also evaluated with nanoindentation and a universal testing machine. The relation between Young’s modulus and sintering time was presented. It was observed that the wettability decreases with sintering time and the Ti alloy powder with particle size < 150 µm had the Young’s modulus that is closer to the modulus of the bone; the optimum sintering time was 5 h.

Pneumonia has contributed greatly to child mortality, especially among children under the ages of five in sub-Saharan Africa, killing more children than the number of children dying from HIV/AIDS. The current methods of diagnosing pneumonia involved physical examination and chest x-ray which are limited by low accuracy, high error margins, higher cost, and stands the risks of inducing cancer. In this work, a low-cost, non-invasive biomedical device was designed and developed to improve accuracy in diagnosing pneumonia. The device functions to detect fluid in a lung consolidated by pneumonia. Dry grouting sponge was used as a phantom for a healthy lung, while a wet sponge was used to mimic a pneumonia-consolidated lung. Surface exciter was used to produce sound waves which travelled through one side of the phantom and are detected on the other end using an electronic stethoscope. The signals detected were digitally analyzed using MATLAB and AUDACITY software. The differences in resonant frequencies from the power spectrum analysis of sound waves as they travelled through the sponges were used to distinguish between a pneumonia-consolidated lung and a healthy lung.

The study presents the mechanical properties of polymer-based composites reinforced with chemically modified banana fibers, by alkalization in different concentrations of sodium hydroxide (NaOH). The fiber weight fraction has a great effect on the mechanical properties of the composites. Stiff composites were obtained at 6 wt% fiber fractions with Young’s modulus of 254.00 ±12.70 MPa. Moreover, the yield strength was 35.70 ±1.79 MPa at 6 wt% fiber fractions. However, the ultimate tensile strength (UTS) and toughness of the composites were obtained at 5 wt% fiber fractions. Statistical analyses were used to ascertain the significant different on the mechanical properties of the fibers and composites. The implication of the results is then discussed for potential applications of PDMS-based composites reinforced with chemically modified banana fibers.

This paper presents the anomalous release kinetics of a cancer drug (prodigiosin) frompoly-n-isopropyl-acrylamide (P(NIPA))-based gels. The release exponents, n, which correspond to the drug release mechanisms, were found to be between 0.41 and 1.40. This is within a range that include Fickian case I (n = 0.45) and non-Fickian diffusion (case II) (n > 0.45) for cylindrical drug-loaded structures. The results, however, suggest that the release exponents, n, correspond mostly to anomalous case II and super case II transport mechanics with sigmoidal characteristics. The drug release kinetics of the P(NIPA)-based hydrogels are well described by bi-dose functions. The observed drug release behavour is related to the porosity of the hydrogels, which can be controlled by cross-linking and copolymerization with acrylamide, which also improves the hydrophilicity of the gels. The paper also presents the effects of cancer drug release on cell survival (%), as well as the cell metabolic activities of treated cells and non-treated cells. The implications of the results are discussed for the development of implantable thermosensitive gels for the controlled release of drugs for localized cancer treatment.

This paper presents the results of a combined experimental and analytical/computational study of viscoelastic cell deformation and detachment from poly-di-methyl-siloxane (PDMS) surfaces. Fluid mechanics and fracture mechanics concepts are used to model the detachment of biological cells observed under shear assay conditions. The analytical and computational models are used to compute crack driving forces, which are then related to crack extension during the detachment of normal breast cells and breast cancer cells from PDMS surfaces that are relevant to biomedical implants. The interactions between cells and the extracellular matrix, or the extracellular matrix and the PDMS substrate, are then characterized using force microscopy measurements of the pull-off forces that are used to determine the adhesion energies. Finally, fluorescence microscopy staining of the cytosketelal structures (actin, micro-tubulin and cyto-keratin), transmembrane proteins (vimentin) and the ECM structures (Arginin Glycine Aspartate - RGD) is used to show that the detachment of cells during the shear assay experiments occurs via interfacial cracking between (between the ECM and the cell membranes) with a high incidence of crack bridging by transmembrane vinculin structures that undergo pull-out until they detach from the actin cytoskeletal structure. The implications of the results are discussed for the design of interfaces that are relevant to implantable biomedical devices and normal/cancer tissue.

This paper presents a study on the synthesis and characterization of hydroxyapatite that can be used to produce dental implants or serves as a replacement for other body hard tissues. The bioceramic material (hydroxyapatite) was derived from bovine bone samples after they were de-fatted and processed to produce particles measuring less than 250 μm. Processed bone powders were calcinated at 750℃ to obtain calcium phosphate compound (hydroxyapatite). This indicated complete elimination of the organic phase of the bone. The synthesized hydroxyapatite was physico-chemically characterized using Fourier transform infrared spectroscopy (FTIR), an optical microscope and scanning electron microscopy (SEM). Hydroxyapatite powder was sintered into a block and then characterized mechanically by measuring its hardness using a Rockwell hardness testing machine. The hydrophilicity and hydrophobicity of the sintered blocked specimens were studied. The average wettability of the substrate, which was a characteristic of the contact angle, was found to be approximately 31.73 degrees. This contact angle value is a measure of the material hydrophilicity. The biostability/corrosive resistance of the sintered samples was simulated in vitro in phosphate buffered saline solution (pH 7.4) by incubating in an optical incubator shaker (set at 60 revolutions per minute) to mimic physiological conditions. The results showed that hydroxyapatite can be extracted economically from a natural source such as bovine bone and can be employed as a restorative biomaterial for dental implants and hard tissue replacement.

The roles of Composite materials in a variety of engineering applications have increased due to their enhanced strength and modulus, especially polymer-based composites which is one of the commercially available composites. The uniaxial tensile properties of polyethylene matrix reinforced with coconut coir fibers has been studied and the results from experiments and analytical models are presented. The compositional dependence of tensile strength, stiffness (elastic modulus), modulus of resilience and ductility are explored for different proportions of the constituent materials through experiments and analytical models. The results from experiments showed that the properties measured were greatly affected by the fiber mass fraction with optimized properties obtained at fiber content of 10 wt%.

This paper presents the results of experimental studies of the mechanical and physical properties of reprocessed polyethylene (PE) waste as reinforcement in laterite bricks for sustainable building applications. The bricks are produced with different volume fractions of polyethylene. The flexural and compressive strengths and the fracture toughness values of the bricks differ upon curing at room temperature for 28days and immersing in water (for 24h, 1week, and 2weeks) before complete curing for 28days. The composite containing 20% by volume PE has the best combination of flexural strength (approximate to 8.2 +/- 0.01MPa), compressive strength (approximate to 5.5 +/- 0.02MPa), and fracture toughness (approximate to 0.94 +/- 0.03MPam) after curing in water for 2weeks. The flexural and compressive strengths and the fracture toughness values are approximate to 4.4 +/- 0.03MPa, 1.9 +/- 0.03MPa, and 0.52 +/- 0.02MPam, respectively, for the composite containing 30% by volume PE after curing the bricks in air. The composites containing 10, 20, and 30% by volume PE, respectively, have initial rates of water absorption of approximate to 1.0, approximate to 1.2, and approximate to 1.4kg/mm2/min. The composite containing 20% by volume PE is more resistant to erosion than the composites containing 10 and 30% by volume PE.