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Dermatoses are essentially caused by infection or free radical aggression, immunoallergic disorders, or can be secondary to general diseases. Management of dermatoses by modern medicine is complex and costly, and the development of alternative treatments is urgent. Opilia amentacea Roxb. is a woody climber plant traditionally used in Burkina Faso for treatment of bad skin diseases. This study was carried out to evaluate the antimicrobial and antioxidant activities of extracts of O. amentacea and to characterize potent fractions. The antimicrobial activity was determined using the disc diffusion and microdilution methods, while antioxidant activity was assessed using the 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) and ferric reducing antioxidant power (FRAP) assays. The content of the plant extracts in polyphenols and flavonoids was also studied. The results revealed several secondary metabolites in the leaves, stems and root bark extracts of the plant, including sterols, triterpenes, and flavonoids and tannins, and a generally high total polyphenol and total flavonoid content. Dichloromethane fractions of leaves (FDFe) and stem barks (FDET) exhibited the best antioxidant activity and were the most active on Gram-positive bacilli. Hexane leaves (FHFe) and hexane root bark (FHER) fractions exhibited the best antifungal activity against Candida tropicalis. High correlation (R2 = 0.932) was found between the total flavonoid content of extracts and ferric-reducing antioxidant power. In view of these results, the present study describes O. amentacea as a potential source of antibacterial, antifungal and antioxidant agents and justifies the traditional uses of the plant as an anti-dermatosis plant.

Abstract Background Febrile illnesses are among the most important reasons for medical consultation in sub-Saharan Africa and are frequently treated with antimicrobials due to the unavailability of appropriate diagnostic tools. This practice leads to antimicrobial resistance, with increasing mortality and morbidity as result. One of the few accessible diagnostic tools available in low resource settings is malaria rapid diagnostic tests (mRDTs) which contributed to reducing the over-prescription of anti-malarials, but cannot guide antibiotic prescriptions. To circumvent this problem, we explored whether combined testing with mRDT and c-reactive protein (CRP) could improve the diagnosis of febrile illnesses and subsequent prescription of antibiotics. Methods Clinical specimens (blood, stool and urine) collected from 396 febrile children (axillary temperature of ≥ 37.5 °C) were analyzed with rapid diagnostic tests (malaria and CRP) and microbiology culture to establish the possible cause of fever. Actual antimicrobial prescriptions given to the children were compared with those that could be given based on combined CRP-malaria testing. Results In total, 68.7% (272/396) of malaria cases were diagnosed by mRDT-Pf-HRP-2. CRP test was positive in 84.3% (334/396) of the children, but bacterial infections were confirmed in 12.4% (49/396) of them. A possible cause of fever could not be established in 20.5% (81/396) of cases. Based on the diagnostic practice in place, 265 of the children with a positive mRDT-Pf-HRP-2 received anti-malarial treatment. Furthermore, 89.5% (111/124) of negative mRDT results received antibiotic treatment and 37.1% (46/124) received antimalarial treatment. Of these 124 cases, 80 had positive CRP tests and 44 negative CRP tests. If the results of CRP testing are considered, 44 CRP/mRDT negative children would not get antibiotic treatment, resulting in a 35.5% reduction in antibiotic prescriptions. However, 2 cases with a bacterial infection would be denied appropriate treatment. Conclusion Combining mRDT-PfHRP2 with CRP testing is particularly useful in children for whom both tests are negative as it results in a reduction of antibiotics prescriptions. However, there is a risk to miss potential severe bacterial infections and a close follow-up of these cases is strongly recommended.

Plasmonic metal nanomaterials have been extensively investigated for their utilizations in biomedical sensing and treatment. In this study, plasmonic Au@Ag core–shell nanoisland films (Au@AgNIFs) were successfully grown onto a glass substrate using a seed-mediated growth procedure. The nanostructure of the Au@AgNIFs was confirmed through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and atomic force microscopy (AFM). The UV-Vis spectra of the Au@AgNIFs exhibited a broad absorption in the visible range from 300 to 800 nm because of the surface plasmon absorption. Under simulated sunlight exposure, the temperature of optimal Au@AgNIF was increased to be 66.9 °C to meet the requirement for photothermal bacterial eradication. Furthermore, the Au@AgNIFs demonstrated a consistent photothermal effect during the cyclic on/off exposure to light. For photothermal therapy, the Au@AgNIFs revealed superior efficiency in the photothermal eradication of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). With their unique nanoisland nanostructure, the Au@AgNIFs exhibited excellent growth efficiency of bacteria in comparison with that of the bare glass substrate. The Au@AgNIFs were also validated as a surface-enhanced Raman scattering (SERS) substrate to amplify the Raman signals of E. coli and S. aureus. By integrating photothermal therapy and SERS detection, the Au@AgNIFs were revealed to be a potential platform for bacterial theranostics.

Gold nanoclusters have revealed great potential as nanoantibiotics due to their superior chemical and physical characteristics. In this study, a peptide with 83 amino acids derived from haptoglobin was utilized as a surface ligand to synthesize gold nanoclusters via a facile hydrothermal approach. Characterization of the structural and optical properties demonstrated the successful synthesis of derived haptoglobin-conjugated gold nanoclusters. The spherical derived haptoglobin-conjugated gold nanoclusters exhibited a (111) plane of cubic gold and an ultra-small size of 3.6 ± 0.1 nm. The optical properties such as ultraviolet-visible absorption spectra, X-ray photoelectron spectroscopy spectra, fluorescence spectra, and Fourier transform infrared spectra also validated the successful conjugation between the derived haptoglobin peptide and the gold nanoclusters surface. The antibacterial activity, reactive oxygen species production, and antibacterial mechanisms of derived haptoglobin-conjugated gold nanoclusters were confirmed by culturing the bacterium Escherichia coli with hemoglobin to simulate bacteremia. The surface ligand of the derived haptoglobin peptide of derived haptoglobin-conjugated gold nanoclusters was able to conjugate with hemoglobin to inhibit the growth of Escherichia coli. The derived haptoglobin-conjugated gold nanoclusters with an ultra-small size also induced reactive oxygen species production, which resulted in the death of Escherichia coli. The superior antibacterial activity of derived haptoglobin-conjugated gold nanoclusters can be attributed to the synergistic effect of the surface ligand of the derived haptoglobin peptide and the ultra-small size. Our work demonstrated derived haptoglobin-conjugated gold nanoclusters as a promising nanoantibiotic for combating bacteremia.

Globally, breast cancer is one of the most prevalent diseases, inducing critical intimidation to human health. Lipid-based nanomaterials have been successfully demonstrated as drug carriers for breast cancer treatment. To date, the development of a better drug delivery system based on lipid nanomaterials is still urgent to make the treatment and diagnosis easily accessible to breast cancer patients. In a drug delivery system, lipid nanomaterials have revealed distinctive features, including high biocompatibility and efficient drug delivery. Specifically, a targeted drug delivery system based on lipid nanomaterials has inherited the advantage of optimum dosage and low side effects. In this review, insights on currently used potential lipid-based nanomaterials are collected and introduced. The review sheds light on conjugation, targeting, diagnosis, treatment, and clinical significance of lipid-based nanomaterials to treat breast cancer. Furthermore, a brighter side of lipid-based nanomaterials as future potential drug delivery systems for breast cancer therapy is discussed.

The artificial repair of tooth enamel is still an urgent requirement because it has a complicated and well-arranged structure. Herein, calcium phosphate nanoclusters (CaP NCs) were synthesized, via a facile approach, for application in the repair of tooth enamel erosion. Structural and optical characterizations validated the successful preparation of spherical CaP NCs, with an average size of 2.1 ± 0.11 nm. By evaporating the ethanol and triethylamine (TEA) solvents, pure CaP was produced, which was further used to repair the tooth enamel. Simulated caries lesions were achieved via phosphoric acid etching to cause damage to enamel rods. After repair, the damaged enamel rods were directly covered with CaP. According to microhardness testing, after repair with CaP NCs, the hardness value of the tooth enamel with acid etching increased to a similar level to that of normal tooth enamel. The results of the microhardness test indicated that CaP NCs revealed great potential for repairing tooth enamel erosion. Our work demonstrates a promising potential for treating the early stage of tooth erosion with CaP NCs. Based on these findings, we believe that stable CaP NCs can be employed as a precursor for the tunable, effective repair of tooth enamel in the near future.

Light-responsive nanocomposites have become increasingly attractive in the biomedical field for antibacterial applications. Visible-light-activated metallic molybdenum disulfide nanosheets (1T-MoS2 NSs) and plasmonic gold nanorods (AuNRs) with absorption at a wavelength of 808 nm were synthesized. AuNR nanocomposites decorated onto 1T-MoS2 NSs (MoS2@AuNRs) were successfully prepared by electrostatic adsorption for phototherapy applications. Based on the photothermal effect, the solution temperature of the MoS2@AuNR nanocomposites increased from 25 to 66.7 °C after 808 nm near-infrared (NIR) laser irradiation for 10 min. For the photodynamic effect, the MoS2@AuNR nanocomposites generated reactive oxygen species (ROS) under visible light irradiation. Photothermal therapy and photodynamic therapy of MoS2@AuNRs were confirmed against E. coli by agar plate counts. Most importantly, the combination of photothermal therapy and photodynamic therapy from the MoS2@AuNR nanocomposites revealed higher antibacterial activity than photothermal or photodynamic therapy alone. The light-activated MoS2@AuNR nanocomposites exhibited a remarkable synergistic effect of photothermal therapy and photodynamic therapy, which provides an alternative approach to fight bacterial infections.

Plasmonic nanomaterials have been intensively explored for applications in biomedical detection and therapy for human sustainability. Herein, plasmonic gold nanoisland (NI) film (AuNIF) was fabricated onto a glass substrate by a facile seed-mediated growth approach. The structure of the tortuous gold NIs of the AuNIF was demonstrated by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Based on the ultraviolet-visible spectrum, the AuNIF revealed plasmonic absorption with maximum intensity at 624 nm. With the change to the surface topography created by the NIs, the capture efficiency of Escherichia coli (E. coli) by the AuNIF was significantly increased compared to that of the glass substrate. The AuNIF was applied as a surface-enhanced Raman scattering (SERS) substrate to enhance the Raman signal of E. coli. Moreover, the plasmonic AuNIF exhibited a superior photothermal effect under irradiation with simulated AM1.5 sunlight. For photothermal therapy, the AuNIF also displayed outstanding efficiency in the photothermal killing of E. coli. Using a combination of SERS detection and photothermal therapy, the AuNIF could be a promising platform for bacterial theranostics.

Gold nanoclusters (AuNCs) and liquid crystals (LCs) have shown great potential in nanobiotechnology applications due to their unique optical and structural properties. Herein, the hardcore of the 4-cyano biphenyl group for commonly used LCs of 4-cyano-4′-pentylbiphenyl (5CB) was utilized to synthesize 4′-(2-mercaptoethyl)-(1,1′-biphenyl)-4-carbonitrile (TAT-12) based on Suzuki coupling and Appel reaction. The structural and optical properties of thiol-modified TAT-12 LCs were demonstrated by nuclear magnetic resonance (NMR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy and differential scanning calorimetry (DSC). By one-pot synthesis, thiol-modified TAT-12 LCs were used as the ligands to prepare fluorescent gold nanoclusters (AuNCs@TAT-12) according to the Au-S bond between AuNCs and TAT-12. The spectra of UV-vis absorption and X-ray photoelectron spectroscopy (XPS) of AuNCs@TAT-12 indicated that the core of gold of AuNCs@TAT-12 exhibited high gold oxidation states. The fluorescence of AuNCs@TAT-12 was observed with a maximum intensity at ~352 nm coming from TAT-12 on AuNCs@TAT-12 and the fluorescence quantum yield of AuNCs@TAT-12 was calculated to be 10.1%. Furthermore, the fluorescence with a maximum intensity at ~448 nm was attributed to a ligand–metal charge transfer between the ligands of TAT-12 LCs and the core of AuNCs. The image of transmission electron microscopy (TEM) further demonstrated an approximately spherical shape of AuNCs@TAT-12 with an average size of 2.3 nm. A combination of UV-vis absorption spectra, XPS spectra, fluorescence spectra and TEM image, fluorescent AuNCs@TAT-12 were successfully synthesized via one-pot synthesis. Our work provides a practical approach to the synthesis of LCs conjugated AuNCs for future applications in nanobiotechnology.

An upsurge in the multidrug-resistant (MDR) bacterial pestilence is a global cause for concern in terms of human health. Lately, nanomaterials with photothermal effects have assisted in the efficient killing of MDR bacteria, attributable to their uncommon plasmonic, photocatalytic, and structural properties. Examinations of substantial amounts of photothermally enabled nanomaterials have shown bactericidal effects in an optimized time under near-infrared (NIR) light irradiation. In this review, we have compiled recent advances in photothermally enabled nanomaterials for antibacterial activities and their mechanisms. Photothermally enabled nanomaterials are classified into three groups, including metal-, carbon-, and polymer-based nanomaterials. Based on substantial accomplishments with photothermally enabled nanomaterials, we have inferred current trends and their prospective clinical applications.

The roots and leaves of Cochlospermum planchonii and C. tinctorium are widely used in Burkina Faso as medication for malaria treatment. The cochloxanthins, carotenoids, are - at least partially - responsible for the antimalarial activity of Cochlospermum spp.. Because of large variation of cochloxanthin contents in rhizomes and leaves of Cochlospermum spp., the available products are not always reliable. The gold standard method for the quantification of cochloxanthins is HPLC. However, HPLC is expensive, time consuming, and needs experienced personnel. Therefore, for quick analysis of Cochlospermum roots in local pharmacies and companies, we developed a spectrophotometric method that is inexpensive, fast, simple and robust. In our study, we produced ethanolic extracts of market samples of roots of Cochlospermum sp. from Burkina Faso and analysed them in parallel by HPLC and spectrophotometry. The two methods correlated well with an R2 > 0.95 (P