1000/1000
Hot
Most Recent
Photonic devices (sensors, in particular) require that an efficient dynamic control of light at nanoscale through field (electric or optical) variation using substitute low-loss materials. One such option may be plasmonic metasurfaces. Metasurfaces are arrays of optical antenna-like anisotropic structures (sub-wavelength size), which are designated to control the amplitude and phase of reflected, scattered and transmitted components of incident light radiation.
References | Advantages/Disadvantages | Target Analyte | Sensor Configuration | Sensitivity | Frequency (f)/Analyte Concentration Range/Limit of Detection (LOD) |
---|---|---|---|---|---|
[21] | (+) Easy to fabricate at low cost. | biotin and streptavidin | Copper (Cu), Nickel (Ni), and gold (Au) printed on PCB | - | f range: 10.64 GHz to 10.84 GHz |
[22] | (+) Low cost and easy inject printing-based fabrication | No specific analyte stated | Ag nanoparticles on paper and plastic substrate. | - | f range: 0.1 THz to 0.5 THz |
[24] | (+) Minimal number of virus particles can be detected efficiently (-) Sophisticated e-beam lithography was used to fabricate the structure |
60 nm of PRD1 virus and 30 nm of MS2 virus | Metamaterial structure formed by 3 nm-thick Cr followed by 97 nm-thick gold | 6 GHz⋅μm2/particle to 80 GHz⋅μm2/particle | f range: 0.5 THz to 1.5 THz |
[25] | (+) Faster detection in both air and aqueous environments (+) Can detect small number of microorganisms (-) Sophisticated e-beam evaporation-based metal deposition and photolithography |
Yeasts and Escherichia coli BL21 (DE3), Neurospora sitophila (neurospora) and Aspergillus niger (niger) | Cr (2 nm) and Au (98 nm) metal films deposited on Si substrate | ~11.6 GHz/number density | f range: 0.5 THz to 3 THz LOD: 107 units/mL |
[29] | (+) Higher sensitivity for four LC resonator-based SRRs as compared to a single LC resonator | Bovine Serum Albumin | Aluminium layer deposition by metal evaporation method | 85 GHz/RIU | f range: 0.2 THz to 1.2 THz LOD: 1.5 μmol/L |
[30] | (+) Enhanced sensitivity by adding AuNPs | The epidermal growth factor receptor (EGFR) antibody | Cr (20 nm) and Au (100 nm) bilayer film coated with AuNPs and arranged in a bow-tie configuration | 1.5 to 3.9 GHz/pM | f range: 2.2 THz to 2.4 THz Conc. Range: 10 fM to 10 pM |
[33] | (+) Better performance because of the SiNx Film as compared to the bare Si substrate | Doped and undoped protein thin films (silk fibroin) | 200 nm gold patterned on 400 nm thick SiNx film deposited on Si wafer | 4.05 × 10−2 GHz/nm. | f range: 0.1 THz to 1.2 THz |
[34] | (+) High Q factor | Alpha-fetoprotein (AFP) and Glutamine transferase isozymes II (GGT-II) | The 200-nm thickness of gold on the Si wafer | 3.8 GHz/(mu/mL) for GGT-II and 562.6 GHz/(μg /mL) for AFP | f range: 0.4 THz to 1.2 THz |
[39] | (+) FOM > 330 (+) Sensitivity several folds higher than the conventional plasmonic sensor |
Streptavidin-biotin | Au nanorod on alumina matrix | >30,000 nm/RIU | f range: 200 THz to 749 THz LOD: 300 nM |
[40] | (+) high FOM of 590 (+) capable of detecting lower molecular-weight (<500 Da) biomolecules |
Biotin, BSA | gold–Al2O3 and grating-coupled hyperbolic metamaterial structure | 30,000 nm/RIU | f range: 150 THz to 600 THz Conc. Range: 10 pM to 1 µM |
References | Advantages/Disadvantages | Target Analyte | Sensor Configuration | Sensitivity | Frequency (f)/Analyte Concentration Range/Limit of Detection (LOD) |
---|---|---|---|---|---|
[74] | (+) Hot spot region to enhance the plasmonic molecular coupling and improve sensitivity | CO2 and C4H10 | A gap between two gold electrodes | 2.92 × 10−4 ppm−1. |
f range: 60 THz to 150 THz Conc. range: 20 to 388 ppm LOD: 20 ppm |
[75] | (+) compact (+) sensitive (+) Energy-efficient gas detection (+) cascading the spectral responses of MPAs on the emitter and the detector to match the narrow absorption band of the target gas (+) highly scalable due to monolithic integration of MPAs into CMOS devices |
CO2 | Gold-coated Si spacer on a PCB board | 22.4 ± 0.5 ppm·Hz−0.5 | Conc. range: 0 to 5000 ppm |
[76] | (+) Wide detection range (-) Limited to numerical analysis and lacks physical implementation |
CO2 | Nano-cylindrical meta-atoms on a gold layer deposited on a quartz substrate | 17.3 pm/ppm | f range: 294 THz to 319 THz Conc. range: 0 to 524 ppm |
[77] | (+) Fabricated by a low-cost CMOS MEMS technology (+) A high-quality factor of 15.7 (+) features temperature-stable and angular-independent emission characteristics (+) a 5-fold increase in relative sensitivity compared to the conventional blackbody emitter |
CO2 | a cross-shaped top Cu resonator was separated from a Cu backplane by means of a dielectric spacer layer (Al2O3) | 1.7 × 10–4 %/ppm | Conc. range: 0 to 50,000 ppm |
[78] | (+) Two wavelength-based dual-mode multiplexed gas sensing (+) fast response time (≈2 min) |
CO2 | polyethylenimine (PEI) polymer spun coated on AlN-Mo-Si | 500 nm/RIU | Conc. range: 0 to 177 ppm LOD: 40 ppm |
[79] | (+) Multiplexed sensing of gases in a mixture | H2S, CH4, CO2, CO, NO, CH2O, NO2, SO2 | From the top to the bottom are: Au nanodisk antenna, the 80 nm silicon dioxide spacer, the Au backplate, the 75 µm lithium tantalate (LT) substrate and the 100 nm Au bottom electrode | Not stated | Conc. range: 0 to 20,000 ppm LOD: 489, 63, 2, 11, 17, 27, 54 and 104 ppm for H2S, CH4, CO2, CO, NO, CH2O, NO2 and SO2 |
[80] | (+) Highly reliable, re-usable and selective (+) a new signature evolving at 300 MHz |
NO2 | Fe3O4 nanoparticles on two square ring-shaped slots | 0.2 MHz/ppm | f range: 200 MHz to 800 MHz Conc. range: 0 to 110 ppm |
[81] | (+) the presence or absence of H2 can be monitored by direct visual inspection (+) response time of only 10 s (+) low-cost fabrication using a simple electrochemical technique |
H2 and N2 | Bimetallic Au/Pd nanorod on a glass substrate | - | f range: 333 THz to 750 THz LOD: 1% H2 |
[59] | (+) large sensing area (+) high sensitivity at room temperature (+) fast response in 10 min (-) sophisticated ion reactive etching and atomic deposition layer |
H2 | Aluminium-doped Zinc oxide (AZO nanotubes) on SiO2/Si substrate | 0.0006 a.u./% | f range: 250 THz to 333 THz Conc. range: 0.7 to 4% LOD: 0.7% |
References | Advantages/Disadvantages | Target Analyte | Sensor Configuration | Sensitivity | Frequency (f)/Analyte Concentration Range/Limit of Detection (LOD) |
---|---|---|---|---|---|
[71] | (+) real-time (+) fast (+) low cost (+) durable (+) accurate detection |
Clean and waste transformer oil, Corn, olive and cotton oils, branded and unbranded diesels, aniline-doped ethyl-alcohol and benzene-doped carbon tetrachloride |
Copper pad on both front and backside of FR-4 substrate | 250 MHz/ 0.11 εr | f range: 8 GHz to 12 GHz LOD: Not stated (detection was based on separation of resonance peaks) |
[73] | (+) Linear relationship between pesticide concentrations and transmission amplitudes | 2,4-dichlorophenoxy acetic and chlorpyrifos solutions | multiwalled CNT arrays on a silicon substrate | 1.38 × 10−2/ppm from 1–10 ppm and 3.0 × 10−3/ppm over 10 ppm |
Conc. range: 1–10 ppm and 10–80 ppm |
[108] | (+) improved sensitivity due to the integration of inter-digital capacitor (IDC) topology (+) better frequency resolution compared to existing SRRs (+) simple design (+) easy fabrication (+) economical |
Glucose | Copper SRR made on Rogers RT6006 substrate and integrated with PDMS microfluidic channel | 0.026 MHz/(mg/dL) | f range: 3 GHz to 5 GHz Conc. range: 0–5000 mg/dL |
[109] | (+) miniaturised (24*15*0.6 mm3) (+) reusable (+) label-free (+) non-destructive (+) smaller sample volume (4 µL) (+) multi-band sensing (+) better linearity in ethanol sensing (−2.80%) |
Ethanol-water mixture | Copper coated with 3.5 µm thick Ni/Au layer on Rogers 4003c substrate (0.203 mm thick) | 2.1 × 106 Hz/% | Conc. range: 0–100% of ethanol in water-ethanol mixture |
[110] | (+) Tunable response | Haemoglobin, urine |
amorphous GST (aGST) and crystalline GST (cGST) in different design structures | 825–1795 nm/RIU when tested on haemoglobin, and 1000–2333 nm/RIU when tested on urine |
f range: 181 THz to 200 THz Conc. range: 10–40 g/L for haemoglobin, and 0–10 mg/dL for urine |
[111] | (+) Optimised asymmetric electric split-ring resonator (AESRR) topology (+) distinguish liquids and solid dielectric materials with bigger frequency shift and higher sensitivity. (+) low-cost (+) real-time (+) high sensitivity (+) high robustness |
Peanut oil, Corn oil, Sunflower seed oil, Soybean oil, Isopropyl alcohol, ethyl acetate, ethanol |
Copper pad on FR-4 substrate | 0.612 | LOD: Not stated (detection was based on separation of resonance peaks) |
[112] | (+) compact design on a single PCB (+) low cost (+) contactless (+) reusable (+) easy to fabricate |
Ethanol–water mixture | Copper pad on FR-4 substrate | 0.57 | Conc. range: 0–100% of ethanol in water-ethanol mixture |
[113] | (+) high sensitivity detection of scattered data (+) adequate penetration depth |
Glucose | Copper pad on FR-4 substrate | 0.0125 dB/(mg/dL) | f range: 2.2 GHz to 3.8 GHz Conc. range: 100–300 mg/dl |
[114] | (+) Ultralow limit of detection | anti-BSA | Al coated periodic nanopillar arrays | 0.14 ng/mL | f range: 333 THz to 1000 THz Conc. range: 0.001–1000 ng/mL LOD: 1 pg/mL |
[115] | (+) No pretreatment required | Vitamin D | Au coated cross and star shaped nanostructures on silicon substrate |
500–800 nm/RIU | LOD: 86 pM |