Correction to "Review on Metal-Organic Framework Classification, Synthetic Approaches, and Influencing Factors: Applications in Energy, Drug Delivery, and Wastewater Treatment".

[This corrects the article DOI: 10.1021/acsomega.2c05310.].

A bio-ionic liquid based self-healable and adhesive ionic hydrogel for the on-demand transdermal delivery of a chemotherapeutic drug.

The non-invasive nature and potential for sustained release make transdermal drug administration an appealing treatment option for cancer therapy. However, the strong barrier of the stratum corneum (SC) poses a challenge for the penetration of hydrophilic chemotherapy drugs such as 5-fluorouracil (5-FU). Due to its biocompatibility and capacity to increase drug solubility and permeability, especially when paired with chemical enhancers, such as oleic acid (OA), which is used in this work, choline glycinate ([Cho][Gly]) has emerged as a potential substance for transdermal drug delivery. In this work, we examined the possibility of transdermal delivery of 5-FU for the treatment of breast cancer using an ionic hydrogel formulation consisting of [Cho][Gly] with OA. Small angle neutron scattering, rheological analysis, field emission scanning electron microscopy, and dynamic light scattering analysis were used to characterize the ionic hydrogel. The non-covalent interactions present between [Cho][Gly] and OA were investigated by computational simulations and FTIR spectroscopy methods. When subjected to in vitro drug permeation using goat skin in a Franz diffusion cell, the hydrogel demonstrated sustained release of 5-FU and effective permeability in the order: [Cho][Gly]-OA gel > [Cho][Gly] > PBS (control). The hydrogel also demonstrated 92% cell viability after 48 hours for the human keratinocyte cell line (HaCaT cells) as well as the normal human cell line L-132. The breast cancer cell line MCF-7 and the cervical cancer cell line HeLa were used to study in vitro cytotoxicity that was considerably affected by the 5-FU-loaded hydrogel. These results indicate the potential of the hydrogel as a transdermal drug delivery vehicle for the treatment of breast cancer.

Multifunctional Ionic Hydrogel-Based Transdermal Delivery of 5-Fluorouracil for the Breast Cancer Treatment.

Transdermal drug delivery systems (TDDS) are a promising and innovative approach for breast cancer treatment, offering advantages such as noninvasiveness, potential for localized and prolonged drug delivery while minimizing systemic side effects through avoiding first-pass metabolism. Utilizing the distinctive characteristics of hydrogels, such as their biocompatibility, versatility, and higher drug loading capabilities, in the present work, we prepared ionic hydrogels through synergistic interaction between ionic liquids (ILs), choline alanine ([Cho][Ala]), and choline proline ([Cho][Pro]) with oleic acid (OA). ILs used in the study are biocompatible and enhance the solubility of 5-fluorouracil (5-FU), whereas OA is a known chemical penetration enhancer. The concentration-dependent (OA) change in morphological aggregates, that is, from cylindrical micelles to worm-like micelles to hydrogels was formed with both ILs and was characterized by SANS measurement, whereas the interactions involved were confirmed by FTIR spectroscopy. The hydrogels have excellent mechanical properties, which studied by rheology and their morphology through FE-SEM analysis. The in vitro skin permeation study revealed that both hydrogels penetrated 255 times ([Cho][Ala]) and 250 times ([Cho][Pro]) more as compared to PBS after 48 h. Those ionic hydrogels exhibited the capability to change the lipid and keratin arrangements within the skin layer, thereby enhancing the transdermal permeation of the 5-FU. Both ionic hydrogels exhibit excellent biocompatibility with normal cell lines (L-132 cells) as well as cancerous cell lines (MCF-7 cells), demonstrating over 92% cell viability after 48 h in both cell lines. In vitro, the cytotoxicity of the 5-FU-loaded hydrogels was evaluated on MCF-7 and HeLa cell lines. These results indicate that the investigated biocompatible and nontoxic ionic hydrogels enable the transdermal delivery of hydrophilic drugs, making them a viable option for effectively treating breast cancer.

Green Synthetic Approach for the Preparation of Blue Emitting Gold Nanoclusters: A Simple Analytical Method for Detection of Hexaconazole Fungicide.

Blue emissive Argyreia nervosa-capped gold nanoclusters (A. nervosa-AuNCs) were synthesized via a simple environment-friendly method. The developed probe exhibits rapid response towards the target analyte (hexaconazole fungicide). Several characterizations, including FT-IR, UV-visible, fluorescence, HR-TEM, XPS, and fluorescence lifetime, were studied to confirm the formation of A. nervosa-AuNCs. The A. nervosa-AuNCs displayed emission and excitation peaks at 470 and 390 nm, respectively. Furthermore, the quantum yield (QY) of A. nervosa-AuNCs was 21.25%. The as-synthesized A. nervosa-AuNCs showed a good linear response with hexaconazole in the concentration range of 0.025-180 µM, with a detection limit (LOD) of 21.94 nM, indicating A. nervosa-AuNCs could be used as a sensitive and selective probe for detecting hexaconazole through a fluorescence "turn-off" mechanism. The A. nervosa-AuNCs were successfully used to detect hexaconazole in real samples. Moreover, A. nervosa-AuNCs were used as a bio-imaging probe for visualization of Saccharomyces cerevisiae cells.

Fluorescence 'turn-off-on' assays for neomycin sulphate and K+ ions with orange-red fluorescent molybdenum nanoclusters.

Fluorescent metal nanoclusters (MNCs) have found extensive application in recognizing molecular species. Here, orange-red fluorescent Arg-A. paniculata-MoNCs were synthesized using Andrographis paniculata leaf extract, arginine as a ligand, and MoCl5 as a metal precursor. The Arg-A. paniculata-MoNCs complex exhibited a quantum yield (QY) of 16.91% and excitation/emission wavelengths of 400/665 nm. The synthesized Arg-A. paniculata-MoNCs successfully acted as a probe for assaying neomycin sulphate (NS) via fluorescence turn-off and K+ ions via fluorescence turn-on mechanisms, respectively. Moreover, the developed probe was effectively used to develop a cellulose paper strip-based sensor for detection of NS and K+ ions. Arg-A. paniculata-MoNCs demonstrated great potential for sensing NS and K+ ions, with concentration ranges of 0.1-80 and 0.25-110 µM for NS and K+ ions, respectively. The as-synthesized Arg-A. paniculata-MoNCs efficiently detected NS and K+ ions in food and biofluid samples, respectively.

Zinc nitride quantum dots as an efficient probe for simultaneous fluorescence detection of Cu2+ and Mn2+ ions in water samples.

The exceptional ascending heights of graphene (carbon) and boron nitride nanostructures have invited scientists to explore metal nitride nanomaterials. Herein, Zn3N2 quantum dots (QDs) were prepared via a simple hydrothermal route from the reaction between zinc nitrate hexahydrate and ammonia solution that possess efficient strength towards sensing applications of metal ions (Cu2+ and Mn2+). The as-prepared Zn3N2 QDs show bright fluorescence, displaying an emission peak at 408 nm upon excitation at 320 nm, with a quantum yield (QY) of 29.56%. It was noticed that the fluorescence intensity of Zn3N2 QDs linearly decreases with the independent addition of Cu2+ and Mn2+ ions, displaying good linearity in the ranges 2.5-50 µM and 0.05-5 µM with detection limits of 21.77 nM and of 63.82 nM for Cu2+ and Mn2+ ions, respectively. The probe was successfully tested for quantifying Cu2+ and Mn2+ in real samples including river, canal, and tap water, providing good recoveries with a relative standard deviation < 2%. Furthermore, the masking proposition can successfully eliminate the interference if the two metal ions exist together. It was found that thiourea is efficiently able to mask Cu2+ and selectively quenches Mn2+, and L-cysteine is able to halt the quenching potential of Mn2+ and is selectively able to sense Cu2+. The Zn3N2 QDs provide a simple way for the simultaneous detection of both Cu2+ and Mn2+ ions in environmental samples at low sample preparations requirements.

Green Emissive Molybdenum Nanoclusters for Selective and Sensitive Detection of Hydroxyl Radical in Water Samples.

In this work, Cassia tora (C. tora) have been used as a template to synthesize green fluorescent C. tora molybdenum nanoclusters (C. tora-MoNCs) through a green chemistry approach. These C. tora-MoNCs showed a quantum yield (QY) of 7.72% and exhibited a significant emission peak at 498 nm when excited at 380 nm. The as-prepared C. tora-MoNCs had an average size of 3.48 ± 0.80 nm and showed different surface functionality. The as-synthesized C. tora-MoNCs were successfully identified the hydroxyl radical (•OH) via a fluorescence quenching mechanism. Also, fluorescence lifetime and Stern-Volmer proved that after the addition of •OH radicals it was quenched the fluorescence intensity via a static quenching mechanism. The limit of detection is 9.13 nM, and this approach was successfully utilized for sensing •OH radicals in water samples with a good recovery rate.

Serodiagnosis of multiple cancers using an extracellular protein kinase A autoantibody-based lateral flow platform.

Extracellular protein kinase A autoantibody (ECPKA-AutoAb) has been suggested as a universal cancer biomarker due to its higher amounts in serum of several types of cancer patients than that of normal individuals. Herein, we first developed a lateral flow immunoassay (LFIA) tool, using a sandwich format, toward ECPKA-AutoAb in human serum. For this format, 3G2 as a capture antibody was identified using hybridoma technique and a series of screenings where it showed superior capacity to recognize Enzo PKA catalytic subunit alpha (Cα), compared to other PKA antibodies and antigens. Using these components, we performed sandwich ELISA toward a mimic and real sample of ECPKA-AutoAb. As per the results, limit of detection (LOD) was found to be 135 ng/mL and ECPKA-AutoAb levels were higher in various cancer patients than in normal individuals like previous studies. Based on these results, we applied this sandwich format into LFIA tool and found that the LOD of the fabricated LFIA tool showed about 3.8 ng/mL using spiked PKA-Ab, which is significantly improved compared to the LOD of sandwich ELISA. Also, the developed LFIA tool demonstrated a remarkable ability to detect significant differences in ECPKA-AutoAb levels between normal and cancer patients within 15 min, showing a potential for point-of-care (PoC) detection. One interesting point is that our LFIA strip contains an additional conjugation pad II, named because of its position behind the conjugation pad, in which PKA Cα is dried, enabling a sandwich format.

Development of Simple Fluorescence Analytical Strategy for the Detection of Triazophos Using Greenish-Yellow Emissive Carbon Dots Derived from Curcuma longa.

This study describes a new method for synthesizing water-soluble carbon dots (CDs) using "Curcuma longa" (green source) named CL-CDs via a single-step hydrothermal process. The as-synthesized CL-CDs exhibited greenish-yellow fluorescence at 548 nm upon excitation at 440 nm. It shows good water stability and exhibits a quantum yield of 19.4%. The developed probe is utilized for sensing triazophos (TZP) pesticide via a dynamic quenching mechanism, exhibiting favorable linearity ranging from 0.5-500 µM with a limit of detection of 0.0042 µM. The as-prepared CL-CDs probe was sensitive and selective towards TZP. Lastly, the successful application of the CL-CDs-based fluorescent probe in water and rice samples highlights its potential as a reliable and efficient method for the detection of TZP in various real sample matrices. Eventually, bioimaging and biocompatibility aspects of CL-CDs have been assessed on Saccharomyces cerevisiae (yeast) cell and lung cancer (A549) cell lines, respectively.

Development of Copper Nanoclusters-Based Turn-Off Nanosensor for Fluorescence Detection of Two Pyrethroid Pesticides (Cypermethrin and Lambda-Cyhalothrin).

Fluorescent copper nanoclusters (Cu NCs) were synthesized by using Withania somnifera (W. somnifera) plant extract as a biotemplate. Aqueous dispersion of W. somnifera-Cu NCs displays intense emission peak at 458 nm upon excitation at 350 nm. This fluorescence emission was utilized for the detection of two pyrethroid pesticides (cypermethrin and lambda-cyhalothrin) via "turn-off" mechanism. Upon the addition of two pyrethiod pesticides independently, the fluorescence emission of W. somnifera-Cu NCs was gradually decreased with increasing concentrations of both pesticides. It was noticed that the decrease in emission intensity at 458 nm was linearly dependent on the logarithm of both pesticides concentrations in the ranges of 0.01-100 µM and of 0.05-100 µM for cypermethrin and lambda-cyhalothrin, respectively. Consequently, the limits of detection were found to be 27.06 and 23.28 nM for cypermethrin and lambda-cyhalothrin, respectively. The as-fabricated W. somnifera-Cu NCs acted as a facile sensor for the analyses of cypermethrin and lambda-cyhalothrin in vegetables (tomato and bottle gourd), which demonstrates that it could be used as portable sensing platform for assaying of two pyrethroid pesticides in food samples.

Synthesis of Greenish-Yellow Fluorescent Copper Nanocluster for the Selective and Sensitive Detection of Fipronil Pesticide in Vegetables and Grain Samples.

In this paper, a new synthetic route is introduced for the synthesis of high-luminescent greenish-yellow fluorescent copper nanoclusters (PVP@A. senna-Cu NCs) using Avaram senna (A. senna) and polyvinylpyrrolidone (PVP) as templates. A. senna plant extract mainly contains variety of phytochemicals including glycosides, sugars, saponins, phenols, and terpenoids that show good pharmacological activities such as anti-inflammatory, antioxidant, and antidiabetic. PVP is a stable and biocompatible polymer that is used as a stabilizing agent for the synthesis of PVP@A. senna-Cu NCs. The size, surface functionality, and element composition of the fabricated Cu NCs were confirmed by various analytical techniques. The as-prepared greenish-yellow fluorescent Cu NCs exhibit significant selectivity towards fipronil, thereby favoring to assay fipronil pesticide with good linearity in the range of 3.0-30 µM with a detection limit of 65.19 nM. More importantly, PVP@A. senna-Cu NCs are successfully applied to assay fipronil in vegetable and grain samples.

Synthesis of copper nanoclusters from Bacopa monnieri leaves for fluorescence sensing of dichlorvos.

In this work, a facile one-step green synthesis was developed for the fabrication of blue fluorescent copper nanocluster (Brahmi-CuNCs) from the extract of Bacopa monnieri (common name is Brahmi) via a microwave method. The as-prepared Brahmi-CuNCs emitted blue fluorescence at 452 nm when excited at 352 nm and showed a quantum yield of 31.32%. Brahmi-derived blue fluorescent CuNCs acted as a probe for fluorescence sensing of dichlorvos. Upon the addition of dichlorvos, the blue emission for Brahmi-CuNCs was gradually turned off, favouring establishment of a calibration graph in the range 0.5-100 µM with a detection limit of 0.23 µM. The as-synthesized Brahmi-CuNCs exhibited marked sensitivity and selectivity towards dichlorvos, favourable for assaying dichlorvos in various samples (cabbage, apple juice, and rice).

Fluorescence "Turn OFF-ON" detection of Fe3+ and propiconazole pesticide using blue emissive carbon dots from lemon peel.

In this study, water-soluble carbon dots (CDs) were employed as a novel fluorescence "turn OFF-ON" sensor to detect Fe3+ ions in pharmaceutical sample and propiconazole (PC) in food samples. Blue fluorescent "LPCDs" are synthesized from the lemon peel that exhibited emission at 468 nm when excited at 378 nm. The average size of the as-prepared LPCDs is 2.03 nm, displaying a quantum yield of 32 %. Fluorescence "turn OFF-ON" strategy was developed for sensing of Fe3+ ion and PC, demonstrating favorable linearity in the range of 0.5-180 µM and 0.1-40 µM with the detection limits of 0.18 µM and 0.054 µM for Fe3+ and PC, respectively. Further, LPCDs-loaded cellulose paper was used as visual reader to detect Fe3+ and PC. This approach was effectively applied to detect Fe3+ and PC in pharmaceutical and vegetable samples.

Synthesis of multicolor silver nanostructures for colorimetric sensing of metal ions (Cr3+, Hg2+ and K+) in industrial water and urine samples with different spectral characteristics.

In this work, we have synthesized four different color (yellow, orange, green, and blue (multicolor)) silver nanostructures (AgNSs) by chemical reduction method where silver nitrate, sodium borohydride and hydrogen peroxide were used as reagents. The as-synthesized multicolor AgNSs were successfully functionalized with bovine serum albumin (BSA) and applied as a colorimetric sensor for the assaying of metal cations (Cr3+, Hg2+, and K+). The addition of metal ions (Cr3+, Hg2+, and K+) into BSA functionalized AgNSs (BSA-AgNSs) causes the aggregation of BSA-AgNSs, and are accompanied by visual color changes with red or blue shift in the surface plasmon resonance (SPR) band of BSA-AgNSs. The BSA-AgNSs show different SPR characteristic for each metal ions (Cr3+, Hg2+, and K+) with exhibiting different spectral shift and color change. The yellow color BSA-AgNSs (Y-BSA-AgNSs) act as a probe for sensing Cr3+, orange color BSA-AgNSs (O-BSA-AgNSs) act as probe for Hg2+ ion assay, green color BSA-AgNSs (G-BSA-AgNSs) act as a probe for the assaying of both K+ and Hg2+, and blue color BSA-AgNSs (B-BSA-AgNSs) act as a sensor for colorimetric detection of K+ ion. The detection limits were found to be 0.26 µM for Cr3+ (Y-BSA-AgNSs), 0.14 µM for Hg2+ (O-BSA-AgNSs), 0.05 µM for K+ (G-BSA-AgNSs), 0.17 µM for Hg2+ (G-BSA-AgNSs), and 0.08 µM for K+ (B-BSA-AgNSs), respectively. Furthermore, multicolor BSA-AgNSs were also applied for assaying of Cr3+, and Hg2+ in industrial water samples and K+ in urine sample.

Microwave-assisted synthesis of blue fluorescent molybdenum nanoclusters with maltose-cysteine Schiff base for detection of myoglobin and γ-aminobutyric acid in biofluids.

The fabrication of stable fluorescent MoNCs (molybdenum nanoclusters) in aqueous media is quite challenging as it is not much explored yet. Herein, we report a facile and efficient strategy for fabricating MoNCs using 2,3 dialdehyde maltose-cysteine Schiff base (DAM-cysteine) as a ligand for detecting myoglobin and γ-aminobutyric acid (GABA) in biofluids with high selectivity and sensitivity. The DAM-cysteine-MoNCs displayed fluorescence of bright blue color under a UV light at 365 nm with an emission peak at 444 nm after excitation at 370 nm. The synthesized DAM-cysteine-MoNCs were homogeneously distributed with a mean size of 2.01 ± 0.98 nm as confirmed by the high-resolution transmission electron microscopy (HR-TEM). Further, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) techniques were utilized to confirm the elemental oxidation states and surface functional groups of the DAM-cysteine-MoNCs. After the addition of myoglobin and GABA, the emission peak of DAM-cysteine-MoNCs at 444 nm was significantly quenched. This resulted in the development of a quantitative assay for the detection of myoglobin (0.1-0.5 µM) and GABA (0.125-2.5 µM) with the lower limit of detection as 56.48 and 112.75 nM for myoglobin and GABA, respectively.

Functionalization of Gold Nanostars with Melamine for Colorimetric Detection of Uric Acid.

Gold nanostars (AuNSs) are synthesized using a seed-mediated growth method. The synthesized AuNSs solution is stable and shows a localized surface plasmon resonance (LSPR) band in the visible range, which is confirmed using ultraviolet-visible (UV-Vis) spectroscopy. Furthermore, the as-synthesized AuNSs were functionalized with melamine and used as a sensor for the colorimetric detection of uric acid (UA). The detection mechanism could be assessed through various analytical techniques such as UV-Vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), zeta potential, field emission scanning electron microscopy (FE-SEM), and transmission electron microscopic techniques. These methods exhibited a good linear regression between the absorption ratio of LSPR band of melamine-AuNSs and the concentration of UA (0-120 µM), with the detection limit of 8.50 nm. As a result, UA was quantitatively detected in biofluids by using melamine-AuNSs as a colorimetric sensor, revealing melamine-AuNSs-based colorimetric approach which could be used as a simple platform for UA assay in biofluids.

Perspectives of different colour-emissive nanomaterials in fluorescent ink, LEDs, cell imaging, and sensing of various analytes.

In the past 2 decades, multicolour light-emissive nanomaterials have gained significant interest in chemical and biological sciences because of their unique optical properties. These materials have drawn much attention due to their unique characteristics towards various application fields. The development of novel nanomaterials has become the pinpoint for different application areas. In this review, the recent progress in the area of multicolour-emissive nanomaterials is summarized. The different emissions (white, orange, green, red, blue, and multicolour) of nanostructure materials (metal nanoclusters, quantum dots, carbon dots, and rare earth-based nanomaterials) are briefly discussed. The potential applications of different colour-emissive nanomaterials in the development of fluorescent inks, light-emitting diodes, cell imaging, and sensing devices are briefly summarized. Finally, the future perspectives of multicolour-emissive nanomaterials are discussed.

Advances in Ultra-small Fluorescence Nanoprobes for Detection of Metal Ions, Drugs, Pesticides and Biomarkers.

Identification of trace level chemical species (drugs, pesticides, metal ions and biomarkers) plays key role in environmental monitoring. Recently, fluorescence assay has shown significant advances in detecting of trace level drugs, pesticides, metal ions and biomarkers in real samples. Ultra-small nanostructure materials (metal nanoclusters (NCs), quantum dots (QDs) and carbon dots (CDs)) have been integrated with fluorescence spectrometer for sensitive and selective analysis of trace level target analytes in various samples including environmental and biological samples. This review summarizes the properties of metal NCs and ligand chemistry for the fabrication of metal NCs. We also briefly summarized the synthetic routes for the preparation of QDs and CDs. Advances of ultra-small fluorescent nanosensors (NCs, QDs and CDs) for sensing of metal ions, drugs, pesticides and biomarkers in various sample matrices are briefly discussed. Additionally, we discuss the recent challenges and future perspectives of ultra-small materials as fluorescent sensors for assaying of wide variety of target analytes in real samples.

Applications of advanced MXene-based composite membranes for sustainable water desalination.

MXenes are an innovative class of 2D nanostructured materials gaining popularity for various uses in medicine, chemistry, and the environment. A larger outer layer area, exceptional stability and conductivity of heat, high porosity, and environmental friendliness are all characteristics of MXenes and their composites. As a result, MXenes have been used to produce Li-ion batteries, semiconductors, water desalination membranes, and hydrogen storage. MXenes have recently been used in many environmental remediations, frequently surpassing conventional materials, to treat groundwater contamination, surface waters, industrial and municipal wastewaters, and desalination. Due to their outstanding structural characteristics and the enormous specific surface area, they are widely utilized as adsorbents or membrane materials for the desalination of seawater. When used for electrochemical applications, MXene-composites can deionize via Faradaic capacitive deionization (CDI) and adsorb various organic and inorganic pollutants to treat the water. In general, as compared to other 2D nanomaterials, MXene has superb characteristics; because of their magnificent characteristics and they exhibit strong desalination capability. The current review paper discusses the desalination capability of MXenes and their composites. Focusing on the desalination capacity of MXene-based nanomaterials, this study discusses the characteristics and synthesis techniques of MXenes their composites along with their ion-rejection capability and pervaporation desalination of water via MXene-based membranes, capacitive deionization capability, solar desalination capability. Furthermore, the challenges and prospects of MXenes and their composites are highlighted.