ZnO QDs Research Articles

Performance Optimization of ZnO Nanorods ETL Based Hybrid Perovskite Solar Cells With Different Seed Layers

This article discusses the direct effect of the seed layers on the growth of the ZnO nanorods (ZNRs) and related photovoltaic parameters of the hybrid perovskite solar cell (PSC). Four different types of ZnO seed layer samples are prepared to analyze the growth of ZNRs over the respective seed layers. Various device parameters for the respective PSCs made of different seed layers are investigated. The ZnO quantum dot-based seed layer shows the well-aligned, vertical, and uniform distribution of ZNRs and improves SC parameters over the other three samples. The ZnO seed layer deposited via drop cast methods results in less density, random, and nonuniform distribution of the ZNRs. The surface morphology, optical absorption, transmission, and crystalline structure were analyzed with high resolution scanning electron microscopy (HRSEM), TEM, UV-visible absorption, and X-ray diffraction (XRD) techniques. 10.69&#x0025; of power conversion efficiency with improved open-circuit voltage (<inline-formula> <tex-math notation="LaTeX">${V}_{OC}$ </tex-math></inline-formula>) of 1.01 V is achieved for device structure, fluorine doped tin oxide (FTO)/ZnO QDs seed layer/ZNRs/perovskite/poly[bis(4-phenyl)(2,5,6-trimethylphenyl)amine (PTAA)/gold (Au).

Active removal of anionic azo dyes (MO, CR, EBT) from aqueous solution by potential adsorptive capacity of zinc oxide quantum dots

AbstractBACKGROUNDOrganic dyes are extremely hazardous waste toxins because they can harm all living organisms as well as the environment. Among them, azo dyes are the most harmful, containing a non‐degradable azo group (NN); these dyes are highly hazardous for both humans and animals, even in low concentration. This research study aims to remove hazardous anionic azo dyes from aqueous solutions by a simple adsorption method using zinc oxide quantum dots (ZnO QDs) synthesized by a facile precipitation method.RESULTSAs synthesized, ZnO QDs were characterized by transmittance electron microscopy, atomic force microscopy, X‐ray powder diffraction, Fourier transform infrared spectroscopy, zeta potential and Brunauer–Emmett–Teller. The azo dyes Methyl Orange (MO), Congo Red (CR) and Eriochrome Black‐T (EBT) have been removed actively from an aqueous solution using the high adsorption characteristic of ZnO QDs. The results demonstrated that the adsorbent was efficient even at a low concentration at 0.05 g L−1. The maximum adsorption capacity of ZnO QDs at 27 ± 1 °C was 102.9, 124.3 and 60 mg L−1 for MO, CR and EBT, respectively, and all these results have been observed in just 30 min. A pseudo‐second‐order and Langmuir isotherm model satisfactorily suited the dye adsorption data and, up to three cycles, the ZnO QDs demonstrated outstanding reusability.CONCLUSIONZnO QDs showed not only efficient removal of individual dyes but also simultaneous removal of azo dyes from mixture solution and proved to be an effective, eco‐friendly, low‐cost adsorbent for dye decontamination in wastewater. © 2022 Society of Chemical Industry (SCI).

Green synthesis and optimization of zinc oxide quantum dots using the Box–Behnken design, with anticancer activity against the MCF-7 cell line

A green strategy and cost-effective approach was adapted to prepare Zinc oxide quantum dots (ZnO QDs) for biomedical applications. The prepared ZnO QDs may hold great promise as sensing scanners for diagnostics and therapy, as demonstrated in our current study. Zinc sulfate, Azadirachta indica, Aloe vera gel and Catharanthus roseus leaves extract were used to synthesize a novel natural Zinc oxide bionanocomposite (ZnO BC) and used as a precursor to prepare ZnO QDs by microwave-assisted technique. The ZnO BC was characterized by SEM–EDX, FT-IR, XRD, Zeta potential, and particle size analysis. The optical properties of QDs were investigated using UV and PL spectrophotometers. Experimental factors like the concentrations of ZnO Nps, C. roseus, and Aloe vera were evaluated using Box–Behnken design (BBD). MTT and hemolysis assay was performed using ZnO BC and ZnO QDs. Maximum absorbance was observed at optimized values of 0.5% ZnO Nps, 1 g A. vera gel, and 0.5 ml C. roseus leaf extract of ZnO QDs against BBD. There was a decreased viability rate, ranging from 60 to 15% for 0.5 mg/ml ZnO BC and 45 to 5% for 5 mg/ml ZnO QDs which revealed a tenfold decrease in cell viability with less concentration scale for 5 mg/ml of ZnO QDs when compared with that of 0.5 mg/ml ZnO BC. Also, the hemolysis test shows that the hemolysis ratio was below 0.5%, indicating non-hemolysis of ZnO QDs. Cellular morphology by results was supported by phase-contrast microscopy images. Good biocompatibility and high anticancer activity were noticed for ZnO QDs when compared to ZnO BC and provide versatile applications in the field of nano-biomedicine.Graphical abstract

Distinctive roles of graphene oxide, ZnO quantum dots, and their nanohybrids in anti-corrosion and anti-fouling performance of waterborne epoxy coatings

In this research, the amino-silane functionalized ZnO quantum dots (F-ZnO QDs), graphene oxide (F-GO), and their nanohybrids (F-GO@ZnO QDs) are used as effective nanofillers to improve the anti-corrosion and anti-fouling properties of waterborne epoxy coatings. The synthesized nanomaterials before and after silane functionalization are characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. Then, the nanocomposite waterborne epoxy coatings loaded with 0.1 wt% F-ZnO QDs, F-GO, and F-GO@ZnO QDs are prepared through solution mixing method. The effects of different nanofillers on the surface roughness, water contact angle, pull-off adhesion strength, fracture surface, and corrosion resistance of the nanocomposite coatings are considered. The results reveal that the uniformly dispersed F-GO@ZnO QDs in the fracture surface of the coating could provide the highest barrier and corrosion resistance on the steel substrates. Meanwhile, the nanocomposite coatings have higher water contact angle and higher adhesion strength to the substrates. The anti-bacterial and anti-fouling properties of the nanocomposite coatings have also been confirmed. The multifunctional performance of the epoxy/F-GO@ZnO QDs is assigned to the synergy effect between the GO, ZnO QDs, and amino-silane; exhibiting the importance of the nanohybrids to combine the advantages of different nanomaterials in one coating system.

Photoluminescence and Electron Paramagnetic Resonance Spectroscopy for Revealing Visible Emission of ZnO Quantum Dots

AbstractBoth PL and EPR are simultaneously adopted to systematically elucidate the defect centers of green luminescence (GL) as well as the EPR peak g = 1.96 of ZnO and the relationship between them. The PL of ZnO QDs reveals that GL of 2.21–2.31 eV disappears at excitation wavelengths &gt; 400 nm. This is related to the electronic transition from conduction band (CB), or shallow donor defect centers, to deep defects of VZn‐H complexes at ≈0.9 eV above the valence band (VB). The EPR peak g = 1.96 emerged only when irradiated with light shorter than 400 nm, which is explicitly correlated with the electrons trapped in the CB or the shallow donors participating in the GL. A spin‐spin relaxation time (T2) estimated from the peak‐to‐peak line width ΔHpp in the EPR signal is ≈17.5–52.5 ns, which is two orders of magnitude longer than known values for bulk or thin‐film ZnO.

Structural, optical and electrical investigation of low-temperature processed zinc oxide quantum dots based thin films using precipitation-spin coating on flexible substrates

Undoped zinc oxide quantum dots (ZnO QDs) solution with ∼4 nm average particle size was synthesized via precipitation technique and spin coated on bare polyethylene terephthalate (PET) and indium tin oxide (ITO) coated PET flexible substrates at low temperature to obtain thin films. The structural, optical and electrical properties of the films were demonstrated by using XRD, FESEM, UV–Visible and Hall Effect. Both films exhibited preferred (101) orientation with slightly better crystallinity on bare PET. Film on ITO coated PET substrate has granular structure with grain size and surface roughness of 4.55 nm and 4.50 nm, respectively. Films showed high visible transmittance with calculated optical band gap of 3.31 eV and 3.35 eV; and refractive index 2.26 and 2.24 respectively, indicating a red shift in the ZnO/ITO/PET in comparison to ZnO/PET. Resistivity of 1.2 × 10−3 Ω cm was achieved with ZnO/ITO/PET electron mobility that surpassed reported hydrothermally synthesized ZnO QDs.

Preparation of pro-angiogenic, antibacterial and EGCG-modified ZnO quantum dots for treating bacterial infected wound of diabetic rats

The complex wound environment and abnormalities in self-metabolism of diabetic skin defects lead to impaired angiogenesis, which can easily lead to bacterial infection and increased inflammation. Therefore, there is an urgent need for multifunctional composites with antimicrobial and pro-angiogenic properties to improve the current therapeutic outcomes of diabetic wounds. In this study, we described an EGCG-modified zinc oxide quantum dots (ZnO QDs) hydrogel (ZnO-EGCG@H) for the treatment of delayed diabetic wounds. In vitro antimicrobial assays showed that ZnO-EGCG@H effectively cleared 95.6% of MRSA and 97% of AmprE. coli with good bactericidal activity. Western blotting assay analysis showed that ZnO-EGCG@H downregulated trauma inflammatory factors (TNF-α, IL-6) by 46.9% and 57%, respectively, while upregulating 1.7-fold VEGF and 2-fold EGF, accelerating wound healing by reducing inflammatory response and promoting proliferation of vascular endothelial cells and skin epidermal cells. After 15 days of ZnO-EGCG@H treatment, the rate of skin lesion closure in rats was 96.3%, which was much better than that of 65.4% in the control group. Safety experiments showed that ZnO-EGCG@H was reassuringly biocompatible and harmless to vital organs. The obtained results suggested that ZnO-EGCG@H had the potential to be a safe and effective treatment method with a promising future as a diabetic wound treatment material.

Multi-sites N-halamine antibacterial agent loaded on mesoporous silica nanoparticles with pH stimulus response

A bactericidal composite material contains a new type of N-halamine with three high bactericidal sites, and loaded the N-halamine in mesoporous silica nanoparticles (MSN), used ZnO quantum dots (ZnO QDs) as a capping gate for pH stimulus response. The N-halamine precursor NDAM was prepared by the amidation reaction of 2,5-dioxo-1,3-diazolidin-4-ylacetic acid and methacrylamide, which contains one imide and two amides NH bonds. After chlorination, three NH bonds were converted into three N-halamine sites, and the oxidative chlorine content was greatly increased. ZnO QDs have the ability to respond to pH stimuli and play a synergistic antibacterial effect with multi-site N-halamine. The antibacterial activity of MSN-AA-NDAM@ZnO nanoparticles against Gram-negative bacteria (E. coli) and Gram-positive bacteria (S. aureus) were studied by bacterial experiments. Compared with the single components (MSN-AA-NDAM-Cl and MSN@ZnO), the antibacterial activity of MSN-AA-NDAM@ZnO nanoparticles showed stronger antibacterial activity due to the synergistic bactericidal effect. This pH-responsive N-halamine bactericidal material provides a new idea in the field of antibacterial and has great application potential.

Probing Nanoscale Interactions of Antimicrobial Zinc Oxide Quantum Dots on Bacterial and Fungal Cell Surfaces (Adv. Mater. Interfaces 3/2022)

Antimicrobial Zinc Oxide Quantum Dots In article number 2101484, Sheeana Gangadoo, Enrico Della Gaspera, James Chapman, Vi Khanh Truong, and co-workers report that utilizing 5 nm zinc oxide quantum dots (ZnO QDs) result in rapid and high antimicrobial performance against methicillin-resistant Staphylococcus aureus and highly pathogenic yeast Candida auris cells. ZnO QDs are shown to adhere and cluster around microbial cell surfaces, resulting in cell membrane damage.

ZnO quantum dots a novel nanomaterial for various applications: Recent advances and challenges

Globally, in the recent era of 22nd century, ZnO quantum dots has gained huge attention of researchers towards its various applications in nano-biotechnology industry. This review article provides substantial approach on several aspects of ZnO quantum dots, its properties, synthesis process, factors affecting the synthesis process. Recent advances and challenges in QDs synthesis and their applications. Though the use of ZnO QDs has shown huge progress, but still so many challenges are there at present like economically cheaper level commercialization of quantum dots, proper in vitro and in vivo application of ZnO quantum dots, so that it can fulfil the need of the industry for various applications.

Physiological responses of pumpkin to zinc oxide quantum dots and nanoparticles

The present study investigated that the potential of soil or foliar applied 15 mg/L zinc oxide quantum dots (ZnO QD, 11.7 nm) to enhance pumpkin (Cucurbita moschata Duch.) growth and biomass in comparison with the equivalent concentrations of other sizes of ZnO particles, ZnO nanoparticles (ZnO NPs, 43.3 nm) and ZnO bulk particles (ZnO BPs, 496.7 nm). In addition, ZnSO4 was used to set a Zn2+ ionic control. For foliar exposure, ZnO QD increased dry mass by 56% relative to the controls and values were 17.3% greater than that of the ZnO NPs particles. The cumulative water loss in the ZnO QD treatment was 10% greater than with ZnO NPs, suggesting that QD could better enhance pumpkin growth. For the root exposure, biomass and accumulative water loss equivalent across all Zn treatments. No adverse effects in terms of pigment (chlorophyll and anthocyanin) contents were evident across all Zn types regardless exposure routes. Foliar exposure to ZnO QD caused 40% increases in shoot Zn content as compared to the control; the highest Zn content was evident in the Zn2+ ionic treatment, although this did not lead to growth enhancement. In addition, the shoot and root content of other macro- and micro-nutrients were largely equivalent across all the treatments. The contents of other nutritional compounds, including amino acids, total protein and sugar, were also significantly increased by foliar exposure of ZnO QD. The total protein in the ZnO QD was 53% higher than the ZnO particle treatments in the root exposure group. Taken together, our findings suggest that ZnO QDs have significant potential as a novel and sustainable nano-enabled agrichemical and strategies should be developed to optimize benefit conferred to amended crops.

Probing Nanoscale Interactions of Antimicrobial Zinc Oxide Quantum Dots on Bacterial and Fungal Cell Surfaces

AbstractThe need for novel antimicrobial agents in response to a growing antibiotic and antimicrobial resistance crisis is now at a breaking point. In this work, the use of 5 nm zinc oxide quantum dots (ZnO QDs), demonstrating rapid and high antimicrobial activity against Gram‐positive methicillin‐resistant Staphylococcus aureus and highly pathogenic yeast Candida auris cells under both non‐photocatalytic and photocatalytic conditions, is showcased. Results show ZnO QDs adhere and cluster around the microbial cell surfaces, and exhibit antimicrobial response toward attached cells, resulting in the cell membrane damage. With the introduction of ultraviolet‐A light, autogenous reactive oxygen species (ROS) are produced and caused further increase in cell membrane/wall disruption, in particular Gram‐negative Escherichia coli. Nanoscale Fourier transform infrared is used to further confirm the intrinsic biochemical changes that occur with the Gram‐negative cell membrane within 30 min and spectra demonstrate that biochemical alterations are achieved for the protein and carbohydrate component of the membrane, which is a common mechanism of ROS damage. Investigation of the cell membrane–material interaction and mechanism is crucial in developing and optimizing effective antimicrobial materials in combating the rise of antimicrobial resistance.

Adsorption behavior of NO2 molecules in ZnO-mono/multilayer graphene core–shell quantum dots for NO2 gas sensor

We demonstrated the sensing properties and adsorption mechanism of NO2 molecules of monolayer graphene and multilayer graphene encapsulated ZnO QDs for NO2 gas adsorption. The gas response value of ZnO-multilayer graphene (ZMLG) QDs was approximately 23 % and 7.2 and 25.5 times higher than that with ZnO-monolayer graphene (ZG) and ZnO QDs, respectively. The surface potential change of ZMLG QDs increased up to 14.25 times compared to ZnO QDs and 6.33 times increased compared to ZG QDs. We proposed an accurate adsorption mechanism for the improvement of the detection behavior that is occured by covering the graphene shells into ZnO QDs by the Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS), and SKPM measurement. These results are expected to increase the accuracy of gas sensor characteristic analysis.

Electrospun Scaffold of Collagen and Polycaprolactone Containing ZnO Quantum Dots for Skin Wound Regeneration.

Nanofibers (NFs) have been widely used in tissue engineering such as wound healing. In this work, the antibacterial ZnO quantum dots (ZnO QDs) have been incorporated into the biocompatible poly (ε-caprolactone)/collagen (PCL/Col) fibrous scaffolds for wound healing. The as-fabricated PCL-Col/ZnO fibrous scaffolds exhibited good swelling, antibacterial activity, and biodegradation behaviors, which were beneficial for the applications as a wound dressing. Moreover, the PCL-Col/ZnO fibrous scaffolds showed excellent cytocompatibility for promoting cell proliferation. The resultant PCL-Col/ZnO fibrous scaffolds containing vascular endothelial growth factor (VEGF) also exhibited promoted wound-healing effect through promoting expression of transforming growth factor-β (TGF-β) and the vascular factor (CD31) in tissues in the early stages of wound healing. This new electrospun fibrous scaffolds with wound-healing promotion and antibacterial property should be convenient for treating wound healing.Supplementary InformationThe online version contains supplementary material available at 10.1007/s42235-021-00115-7.

Probing defects and their implications in pH-controlled ZnO QDs: a theory-aided experimental investigation

Probing defects and their implications in pH-controlled ZnO QDs: a theory-aided experimental investigation

Antibacterial activity of ZnO quantum dots and its protective effects of chicks infected with Salmonella pullorum

In light of emerging antibiotic resistance, synthesis of active, environmental friendly antimicrobial alternatives becomes increasingly necessary. In this study, ZnO quantum dots (ZnO QDs) were developed by the sol–gel method and characterized. The antibacterial activities of ZnO QDs against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Salmonella Pullorum (S. Pullorum) were systematically investigated. Moreover, the protective effects of ZnO QDs on Salmonella-caused pullorosis in chicks were also explored. The results indicated that the size range of ZnO QDs was 3–6 nm. Antibacterial results showed that ZnO QDs treatment inhibited the growth of E. coli, S. aureus, and S. Pullorum in the rate of 87.06 ± 0.98%, 94.75 ± 2.28%, and 85.55 ± 1.15%, respectively. Its excellent antibacterial property was manifested with the minimum inhibitory concentration of 0.7812, 0.0976, and 0.1953 mg ml−1, which may be attributed to the production of reactive oxygen species, the dissolution of Zn2+ ions, and the loss of cell integrity. Furthermore, in the in vivo test, the ZnO QDs effectively reduced the mortality of chicks infected with S. Pullorum via regulating the balance of the intestinal flora, protecting liver and intestine, and modulating the balance of antioxidation systems. This study reveals that ZnO QDs exerts remarkably antibacterial activity in vitro and anti-pullorosis effect in chicks.

Sol-gel fabrication of Ag-Coated ZnO quantum dots nanocomposites with excellent photocatalytic activity

The development of metal/semiconductor photoactive materials has progressed remarkably with respect to heterogeneous photocatalysis. In this study, pristine ZnO quantum dots (ZQ) and Ag/ZQ nanocomposites with different Ag loadings were prepared using a cost-effective method. The synthesized samples were characterized using X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and electron paramagnetic resonance analyses. Photocatalytic experiments indicated that the Ag11/ZQ nanocomposite (Ag content of 11 wt%), exhibited excellent photocatalytic activity for methylene blue degradation. A combination of ultraviolet–visible spectroscopy, photoluminescence spectroscopy, electrochemical impedance spectroscopy, time-resolved photoluminescence analyses, and analog computational analysis were employed to propose the mechanism underlying the enhanced photocatalytic activity of Ag/ZQ nanocomposites. This was attributed to the effective charge transfer to the surface-decorated Ag, which efficiently suppresses electron–hole recombination in the ZQ, as well as oxygen vacancies (V O ) on the ZQ surface provide more reactive sites. Consequently, Ag/ZQ nanocomposites are promising photocatalytic materials for the removal of organic pollutants from wastewater. • Pristine ZnO QDs (ZQ) and Ag/ZQ nanocomposites were obtained by a cost-effective sol-gel approach. • Density functional theory was used to assess the influence of oxygen vacancies on the electronic properties of ZnO. • PL, EIS, and TRPL decay spectra were obtained to precisely inspect the transportation processes of the photocarriers. • The strong charge transmission action of Ag and the presence of oxygen vacancies in ZQ enhanced photocatalytic activity.

Boosting near-infrared photoluminescence efficiency of erbium ions and ZnO quantum dots codoped amorphous silica thin films

Er3+ ions and ZnO QDs codoped amorphous silica thin films are prepared by the modified sol-gel spin-coating technique. By introducing the ZnO QDs as sensitizers, the PL emission intensity of Er3+ ions is enhanced by more than two orders of magnitude. With the increasing annealing temperature, the lengthening PL emission lifetime indicates the gradual passivation of the non-radiative trap states. The thermal quenching behavior of PL emission intensity is analyzed by the temperature-dependent PL spectra. With the increasing annealing temperature, the decrease of activation energy suggests the narrowing of energy level difference between the excited state of Er3+ ions and the defect state of ZnO QDs. The gradually improved phonon-assisted energy transfer efficiency results in the greatly enhanced PL efficiency of Er3+ ions. These results will be a starting point for further research on the sensitization mechanisms in the rare earth ions and wide-bandgap QDs codoped amorphous silica.

Fluorescence ‘turn-on’ probe for Al3+ detection in water based on ZnS/ZnO quantum dots with excellent selectivity and stability

In this work, an efficient and stable fluorescent probe for Al3+ was established. The fluorescent probe based on the fluorescence ‘turn-on’ mode of zinc sulfide crystal composite zinc oxide quantum dots (ZnS/ZnO QDs). The ZnS/ZnO QDs were synthesized via two-step method using L-Cysteine (L-Cys) as a sulfur source and stabilizer. In the synthesis of ZnS/ZnO QDs, the fluorescence of zinc oxide quantum dots (ZnO QDs) decreased and its stability increased in aqueous solution after the addition of L-Cys. In addition, the as-synthesized ZnS/ZnO QDs shows fluorescent enhancement to Al3+. The ZnS/ZnO QDs based fluorescence ‘turn-on’ probe presented wide linear ranges (1 nM–8 μM and 8–100 μM). The availability of as-established sensing probe was also estimated by real water sample tests. Furthermore, the fluorescent enhancing mechanism was carried out by recording the fluorescent lifetime of samples, which might be related to the QDs dispersion and charge transfer weaken.

Synergism of Zinc Oxide Quantum Dots with Antifungal Drugs: Potential Approach for Combination Therapy against Drug Resistant Candida albicans

Candidiasis caused by Candida albicans is one of the most common microbial infections. Azoles, polyenes, allylamines, and echinocandins are classes of antifungals used for treating Candida infections. Standard drug doses often become ineffective due to the emergence of multidrug resistance (MDR). This leads to the use of higher drug doses for prolonged duration, resulting in severe toxicity (nephrotoxicity and liver damage) in humans. However, combination therapy using very low concentrations of two or more antifungal agents together, can lower such toxicity and limit evolution of drug resistance. Herein, 4–6 nm zinc oxide quantum dots (ZnO QDs) were synthesized and their in vitro antifungal activities were assessed against drug-susceptible (G1, F1, and GU4) and resistant (G5, F5, and GU5) isolates of C. albicans. In broth microdilution assay, ZnO QDs exhibited dose dependent growth inhibition between 0 – 200 µg/ml and almost 90% growth was inhibited in all Candida strains at 200 µg/ml of ZnO QDs. Synergy between ZnO QDs and antifungal drugs at sub-inhibitory concentrations of each was assessed by checkerboard analysis and expressed in terms of the fractional inhibitory concentration (FIC) index. ZnO QDs were used with two different classes of antifungals (azoles and polyenes) against Candida isolates: combination 1 (with fluconazole); combination 2 (with ketoconazole); combination 3 (with amphotericin B), and combination 4 (with nystatin). Results demonstrated that the potency of combinations of ZnO QDs with antifungal drugs even at very low concentrations of each was higher than their individual activities against the fungal isolates. The FIC index was found to be less than 0.5 for all combinations in the checkerboard assay, which confirmed synergism between sub-inhibitory concentrations of ZnO QDs (25 µg/ml) and individual antifungal drugs. Synergism was further confirmed by spot assay where cell viabilities of Candida strains were significantly reduced in all combinations, which was clearly evident from the disappearance of fungal cells on agar plates containing antifungal combinations. For safer clinical use, the in vitro cytotoxic activity of ZnO QDs was assessed against HeLa cell line and it was found that ZnO QDs were non-toxic at 25 µg/ml. Results suggested that the combination of ZnO QDs with drugs potentiate antimicrobial activity through multitargeted action. ZnO QDs could therefore offer a versatile alternative in combination therapy against MDR fungal pathogens, wherein lowering drug concentrations could reduce toxicity and their multitargeted action could limit evolution of fungal drug resistance.