Lower Limit Research Articles

Spectrofluorimetric and smartphone-based detection methods for determination of gentamicin

AbstractThis paper presents the development of spectrofluorimetric and smartphone-based detection methods for gentamicin determination using fluorescamine as a reagent. The research included selecting excitation (415 nm) and emission (489 nm) wavelengths, reaction time, and conditions like reagent concentration, and pH of the reaction medium. Moreover, the optimal operating parameters of the smartphone camera, like ISO, white balance, camera shutter, and RGB model channel were selected. Analytical parameters of the developed spectrofluorimetric and smartphone-based methods were estimated including the linear range: 0.04–15.00 mg dm−3 and 0.18–1.20 mg dm−3, respectively, limits of detection and quantification: 0.01 and 0.04 mg dm−3, and 0.06 and 0.18 mg dm−3, respectively, and precision (CV, n = 6): 5.2% and 2.8%, respectively. The proposed approaches were successfully applied to determine gentamicin in pharmaceutical samples. The obtained results were consistent with values declared by manufacturers and satisfactory recovery values, 93.2–113.6% were obtained for both spectrofluorimetric and smartphone-based methods. The developed fluorimetric method with smartphone-based detection provides a low limit of detection specific to spectrofluorimetric methods whereas the measurement system is a simple, easily accessible, compact, and low-cost device. Hence, it can become a competitive alternative to other gentamicin determination methods. Graphical abstract

A Lanthanide-Incorporated Phospho(III)tungstate Aggregate Constructed from [HPIIIW8O31]10- and [W11O39]12- Building Blocks and Its Nanocomposite with CdS for Ultrasensitive Photoelectrochemical Detection of Oxytetracycline.

A novel tartronic acid decorated hexa-CeIII-incorporated phospho(III)tungstate aggregate (C4H12NO)6Na18H2[(HPW8O31)2[W11O39]2(H2TAD)4(H2O)4W4Ce6H2P2O14]·84H2O (1, H3TAD = tartronic acid) was synthesized by a one-step assembly strategy. Its main skeleton is constructed from two [W11O39]12- fragments, two [HPIIIW8O31]10- segments and one H2TAD--ornamented dodecanuclear heterometallic [W4Ce6H2PIII2O14(H2TAD)4(H2O)4]18+ cluster. In the structure, the [HPIIIO3]2- groups not only work as the heteroatom template to induce the formation of lacunary [HPIIIW8O31]10- segments but also function as the connector to bridge Ce3+ cations. With the help of a reaction strategy of combining ultrasonication treatment with the continuous ion layer adsorption method, the 1/CdS composite was constructed and exhibits prominent photoelectrochemical activity. The 1/CdS composite was used as a photoelectrochemical sensor for oxytetracycline detection at 0 V (vs Ag/AgCl), which displays excellent properties with quick response and low limit of detection (0.042 nM). This work can provide some helpful references in the construction of novel PIII-induced polyoxometalates consisting of different building blocks and can extend the applications of polyoxometalate-based nanocomposites into photoelectrochemical detection for antibiotics as well as biomolecules.

2.7 μm backward wave optical parametric oscillator source for CO2 spectroscopy

In this work, a novel 2.7 µm source used for CO2 and H2O vapor spectroscopy using the backward propagating wave of a backward wave optical parametric oscillator (BWOPO) is demonstrated for the first time to our knowledge. The unique properties of BWOPOs eliminate the need for additional spectral narrowing or wavelength stabilization, enabling the use of a multi-longitudinal mode Q-switched pump laser centered around 1030 nm. A full characterization of the source is presented, revealing a central output at 2712 nm, showcasing a temperature tuning of −1.77 GHz/K, and achieving an output pulse energy of 2.3 µJ. Novel methods are introduced for measuring the linewidth and wavelength stability using the ambient laboratory air. These approaches demonstrate a narrow output of 43 pm and establish an upper limit of stability at 65 MHz, with no active means of stabilization. These findings underscore the potential of BWOPOs as a robust platform for future differential absorption lidar (DIAL) systems.

Moving toward Individual Treatment Goals with Pegcetacoplan in Patients with PNH and Impaired Bone Marrow Function

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare, potentially life-threatening haematological disease characterised by chronic complement-mediated haemolysis with multiple clinical consequences that impair quality of life. This post hoc analysis assessed haematological and clinical responses to the first targeted complement C3 inhibitor pegcetacoplan in patients with PNH and impaired bone marrow function in the PEGASUS (NCT03500549) and PRINCE (NCT04085601) studies. For patients with impaired bone marrow function, defined herein as haemoglobin <10 g/dL and absolute neutrophil count <1.5 × 109 cells/L, normalisation of the parameters may be difficult. Indeed, 20% and 43% had normalised haemoglobin in PEGASUS and PRINCE, respectively; 60% and 57% had normalised LDH, and 40% and 29% had normalised fatigue scores. A new set of parameters was applied using changes associated with clinically meaningful improvements, namely an increase in haemoglobin to ≥2 g/dL above baseline, decrease in LDH to ≤1.5× the upper limit of normal, and an increase in fatigue scores to ≥5 points above baseline. With these new parameters, 40% and 71% of PEGASUS and PRINCE patients had improved haemoglobin; 60% and 71% had an improvement in LDH, and 60% and 43% had an improvement in fatigue scores. Thus, even patients with impaired bone marrow function may achieve clinically meaningful improvements with pegcetacoplan.

Search for diphoton decays of an axionlike particle in radiative J/ψ decays

We search for the diphoton decay of a light pseudoscalar axionlike particle, a, in radiative J/ψ decays, using 1010 J/ψ events collected with the BESIII detector. We find no evidence of a signal and set upper limits at the 95% confidence level on the product branching fraction B(J/ψ→γa)×B(a→γγ) and the axionlike particle photon coupling constant gaγγ in the ranges of (3.7–48.5)×10−8 and (2.2–101.8)×10−4 GeV−1, respectively, for 0.18≤ma≤2.85 GeV/c2. These are the most stringent limits to date in this mass region. Published by the American Physical Society 2024

Transparent Perovskite Wafers via Nanocrystals Ordered Coalescence Toward Sensitive and Stable X‐Ray Detection and Imaging

AbstractMetal halide perovskite wafers have shown significant potential in large‐area X‐ray detection and imaging. However, a distinct difference in optical transparency between state‐of‐the‐art perovskite wafers and single crystals indicates the inferior crystal quality of perovskite wafers, which limits the performance and stability of wafer‐based X‐ray detectors. Here, nano‐sized MAPbBr3 powders are utilized to fabricate dense perovskite wafers by low‐temperature hot‐pressing with high transparency above 60% within the 552–800 nm wavelength range. Adjacent nanocrystals assemble following the ordered coalescence mechanism, resulting in the exclusion of nanoscopic pores and crystallographic reorientation. The transparent MAPbBr3 wafer‐based detectors achieve an impressively high X‐ray sensitivity of 1.14 × 105 µC Gyair−1 cm−2 and a low detection limit of 149 nGyair s−1, which is superior to opaque MAPbBr3 wafer detectors (5.64 × 104 µC Gyair−1 cm−2 and 316.7 nGyair s−1) and comparable to MAPbBr3 single‐crystal detectors. Moreover, the detectors demonstrate high uniformity and outstanding stability under continuous X‐ray irradiation of a total dose of up to 5.9 Gyair, equaling to 29 500 times posteroanterior chest examinations. The high sensitivity and low detection limit of the detectors lead to clear X‐ray imaging performance.

Safety and Immunogenicity of Respiratory Syncytial Virus Prefusion F Protein Vaccine when Co-administered with Adjuvanted Seasonal Quadrivalent Influenza Vaccine in Older Adults: A Phase 3 Randomized Trial.

We evaluated co-administration of adjuvanted seasonal quadrivalent influenza vaccine (FLU-aQIV) and respiratory syncytial virus (RSV) prefusion F protein-based vaccine (RSVPreF3 OA) in ≥65-year-olds. This phase 3, open-label trial randomized ≥65-year-olds to receive FLU-aQIV and RSVPreF3 OA concomitantly (Co-Ad) or sequentially, 1 month apart (Control). Primary objectives were to demonstrate the non-inferiority of FLU-aQIV and RSVPreF3 OA co-administration versus sequential administration in terms of hemagglutination inhibition (HI) titers for each FLU-aQIV strain and RSV-A and RSV-B neutralization titers, 1 month post-vaccination. Reactogenicity and safety were also assessed. Overall, 1045 participants were vaccinated (Co-Ad: 523; Control: 522). Non-inferiority of FLU-aQIV and RSVPreF3 OA co-administration versus sequential administration was demonstrated in terms of HI titers for the A/Victoria(H1N1), B/Victoria, and B/Yamagata influenza strains and RSV-A neutralization titers (upper limits [ULs] of 95% confidence intervals [CIs] for adjusted geometric mean titer [GMT] ratios [Control/Co-Ad] ≤1.50) but not for A/Darwin(H3N2) HI titers (95% CI UL = 1.53). The immune response to A/Darwin(H3N2) was further assessed post-hoc using a microneutralization assay; the post-vaccination adjusted GMT ratio (Control/Co-Ad) was 1.23 (95% CI: 1.06-1.42, ie, UL ≤1.50), suggesting an adequate immune response to A/Darwin(H3N2) following co-administration. RSV-B neutralization titers were comparable between groups (95% CI UL for adjusted GMT ratio ≤1.50). Solicited adverse events were mostly mild or moderate and transient; unsolicited and serious adverse event rates were balanced between groups. Adjuvanted FLU-aQIV and RSVPreF3 OA had acceptable reactogenicity/safety profiles when co-administered in ≥65-year-olds, without clinically relevant interference with the immune responses to either vaccine. NCT05568797.

Rapid nanomolar detection of cocaine in biofluids by electrochemical aptamer-based sensor with low-temperature effect for drugged driving screening.

Cocaine is one of the most abused illicit drugs, and its abuse damages the central nervous system and can even lead directly to death. Therefore, the development of simple, rapid and highly sensitive detection methods is crucial for the prevention and control of drug abuse, traffic accidents and crime. In this work, an electrochemical aptamer-based(EAB) sensor based on the low-temperature enhancement effect was developed for the direct determination of cocaine in bio-samples. The signal gain of the sensor at 10°C was greatly improved compared to room temperature, owing to the improved affinity between the aptamer and the target. Additionally, the electroactive area of the gold electrode used to fabricate the EAB sensor was increased 20 times by a simple electrochemical roughening method. The porous electrode possesses more efficient electron transfer and better antifouling properties after roughening. These improvements enabled the sensor to achieve rapid detection of cocaine in complex bio-samples. The low detection limits (LOD) of cocaine in undiluted urine, 50% serum and 50% saliva were 70nM, 30nM and 10nM, respectively, which are below the concentration threshold in drugged driving screening. The aptasensor was simple to construct and reusable, which offers potential fordrugged driving screening in the real world.

In Situ Defect Engineering of Fe-MIL for Self-Enhanced Peroxidase-Like Activity.

Defect engineering is an effective strategy to enhance the enzyme-like activity of nanozymes. However, previous efforts have primarily focused on introducing defects via de novo synthesis and post-synthetic treatment, overlooking the dynamic evolution of defects during the catalytic process involving highly reactive oxygen species. Herein, a defect-engineered metal-organic framework (MOF) nanozyme with mixed linkers is reported. Over twofold peroxidase (POD)-like activity enhancement compared with unmodified nanozyme highlights the critical role of in situ defect formation in enhancing the catalytic performance of nanozyme. Experimental results reveal that highly active hydroxyl radical (•OH) generated in the catalytic process etches the 2,5-dihydroxyterephthalic acid ligands, contributing to electronic structure modulation of metal sites and enlarged pore sizes in the framework. The self-enhanced POD-like activity induced by in situ defect engineering promotes the generation of •OH, holding promise in colorimetric sensing for detecting dichlorvos. Utilizing smartphone photography for RGB value extraction, the resultant sensing platform achieves the detection for dichlorvos ranging from 5 to 300ngmL-1 with a low detection limit of 2.06ngmL-1. This pioneering work in creating in situ defects in MOFs to improve catalytic activity offers a novel perspective on traditional defect engineering.

Dual-mode detection of glucose based on pistol-like DNAzyme-mediated exonuclease-assisted signal cycle.

Detecting glucose accurately and sensitively from clinical samples like tears and saliva is still difficult. We have created a sensor that can detect glucose with high sensitivity and accuracy by combining the use of glucose oxidase (GOx) to catalyze glucose, a pistol-like DNAzyme (PLDz) to transform the signal, gold nanoparticles (AuNPs) to enhance the optical properties and the exonuclease-III (Exo-III) to amplify the signal. As a result, the proposed method exhibits a low detection limit of 7.5pM and a wide detection range covering seven orders of magnitude. The suggested dual-mode strategy provides a sensitive, precise and specific detection method for glucose. Another advantage is that the dual-mode technique significantly improves the precision and consistency of the measurements, demonstrating its immense potential for use in biomedical research and clinical diagnostics.

Disposable electrochemical sensors based on reduced graphene oxide/polyaniline/poly(alizarin red S)-modified integrated carbon electrodes for the detection of ciprofloxacin in milk.

Anelectrochemical sensor based on an electroactive nanocomposite was designedfor the first timeconsisting of electrochemically reduced graphene oxide (ERGO), polyaniline (PANI), and poly(alizarin red S) (PARS) for ciprofloxacin (CIPF) detection. The ERGO/PANI/PARS-modified screen-printed carbon electrode (SPCE) was constructed through a three-step electrochemical protocol and characterized using FTIR, UV-visible spectroscopy, FESEM, CV, LSV, and EIS. The new electrochemical CIPF sensor demonstrated a low detection limit of 0.0021μM, a broad linear range of 0.01 to 69.8μM, a high sensitivity of 5.09 μA/μM/cm2, and reasonable selectivity and reproducibility. Moreover, the ERGO/PANI/PARS/SPCE was successfully utilized to determine CIPF in milk with good recoveries and relative standard deviation (< 5%), which were close to those with HPLC analysis.

WSe2 Negative Capacitance Field-Effect Transistor for Biosensing Applications.

Field-effect transistor (FET) biosensors based on two-dimensional (2D) materials are highly sought after for their high sensitivity, label-free detection, fast response, and ease of on-chip integration. However, the subthreshold swing (SS) of FETs is constrained by the Boltzmann limit and cannot fall below 60 mV/dec, hindering sensor sensitivity enhancement. Additionally, the gate-leakage current of 2D material biosensors in liquid environments significantly increases, adversely affecting the detection accuracy and stability. Based on the principle of negative capacitance, this paper presents for the first time a two-dimensional material WSe2 negative capacitance field-effect transistor (NCFET) with a minimum subthreshold swing of 56 mV/dec in aqueous solution. The NCFET shows a significantly improved biosensor function. The pH detection sensitivity of the NCFET biosensor reaches 994 pH-1, nearly an order of magnitude higher than that of the traditional two-dimensional WSe2 FET biosensor. The Al2O3/HfZrO (HZO) bilayer dielectric in the NCFET not only contributes to negative capacitance characteristics in solution but also significantly reduces the leakage in solution. Utilizing an enzyme catalysis method, the WSe2 NCFET biosensor demonstrates a specific detection of glucose molecules, achieving a high sensitivity of 4800 A/A in a 5 mM glucose solution and a low detection limit (10-9 M). Further experiments also exhibit the ability of the biosensor to detect glucose in sweat.

The Optimization of Aerobic Bacteria Inactivation in Tilapia (Oreochromis niloticus) Fillets using Micro-Nano Bubbles of Carbon Dioxide and Shelf-Life Extension

This study aims to examine the influence of NaOCl, NaCl and contact time on the inactivation of aerobic bacteria in tilapia fillets treated with micro-nano bubbles of CO2 (CO2 MNB) in a washing process of fish fillets, and compared to soaking with tap water and untreated fillets for their shelf-life extensions. Response surface methodology (RSM) with a central composite design was used to compare and predict of the inactivation effects. The fish fillets were soaked in a NaOCl solution before washing with a NaCl solution and CO2 MNB produced from an MNB generator system, maintaining the liquid temperature in the range of 4–7 °C for all experiments. According to the regression analysis from the experimental design, aerobic bacteria inactivation was reduced by 1.509 log CFU/g at 100 mg/L NaOCl, 10%w/v NaCl, and a contact time of 32 min with CO2 MNB. The experimental value of the reduction of aerobic bacteria by 1.503 ± 0.009 log CFU/g (before washing 5.623 log CFU/g; after washing 4.120 log CFU/g) was found after treatment under the aforementioned condition. The number of aerobic bacteria counted on the tilapia fillets treated with the upper condition after being stored at 4 ± 2 °C for 7 d was below the acceptable limits, but untreated and treated with tap water had bacteria counts exceeding the upper microbial limit (6 log CFU/g). The combined results showed that the NaOCl, NaCl solution and CO2 MNB treatment could extend the storage time by more than 7 d.

Damage deformation properties and acoustic emission characteristics of hard-brittle rock under constant amplitude cyclic loading

In order to study the deformation and damage characteristics of the limestone specimens with high strength and brittleness under constant amplitude cyclic loading, the deformation and the acoustic emission (AE) characteristics were analysed, and the relationship between them was sought. The damage variables under different amplitude cyclic loading were defined by AE counts. The results showed that the radial deformation of the limestone specimens was more sensitive and unstable than the axial deformation. The concept of apparent residual strain was proposed to describe the specimen deformation characteristics, and it resulted that the radial apparent residual strain produced at higher stress state would recover at lower stress state. The limestone specimens showed obvious Kaiser effect and Felicity effect under cyclic loading. When the upper limit of the cyclic loading was close to the peak stress of the specimen, the AE counts generated in unloading sections were almost the same as that in the loading sections. The damage was increased as the amplitude and the stress level increased and the unloading process at higher stress level would also lead to the aggravation of damages. Specimens would absorb more energy under cyclic loading than under uniaxial loading. Reasonable driving parameters should be controlled in underground excavation practice, to ensure that the stress level of surrounding rock mass in a periodic stress state is located before peak stress and such that to limit the occurrence of rock burst to a certain extent.

High Thermal Conductive Liquid Crystal Elastomer Nanofibers.

Liquid crystal elastomers (LCEs), consisting of polymer networks and liquid crystal mesogens, show a reversible phase change under thermal stimuli. However, the kinetic performance is limited by the inherently low thermal conductivity of the polymers. Transforming amorphous bulk into a fiber enhances thermal conductivity through the alignment of polymer chains. Challenges are present due to their rigid networks, while cross-links are crucial for deformation. Here, we employ hydrodynamic alignment to orient the LCE domains assisted by controlled in situ cross-linking and to remarkably reduce the diameter to submicrons. We report that the intrinsic thermal conductivity of LCE fibers at room temperature reaches 1.44 ± 0.32 W/m-K with the sub-100 nm diameter close to the upper limit determined in the quasi-1D regime. Combining the outstanding thermal conductivity and thin diameters, we anticipate these fibers to exhibit a rapid response and high force output in thermomechanical systems. The fabrication method is expected to apply to other cross-linked polymers.

Ultrafast Scintillator Based on Zirconium‐Doped Cesium Zinc Chloride Single Crystals and Their Charge Carrier Dynamics

AbstractScintillators have been widely used for high‐energy radiation imaging. It is in great demand and challenge to develop scintillator materials with fast decay time, high scintillation light yield, and low detection limit for high‐resolution imaging applications such as time‐of‐flight positron emission tomography. However, it is still a challenge to develop the ultrafast carrier dynamics to achieve 100% ultrafast decay time with high scintillation light yield. To meet the demand, a series of component‐tunable Cs2ZnCl4: x%Zr single crystals as promising ultrafast scintillators is successfully developed. With 8% of Zr‐dopant (Cs2ZnCl4: 8%Zr), the single crystal exhibits high light yield (28000 photons MeV−1) and low detection limit (51 nGy s−1) under X‐ray excitation. Photo‐induced transient absorption signals on sub‐nanosecond and nanosecond scales ensure almost 100% fast decay time (≈3 ns) in nanoseconds under γ‐ray excitation. In particular, the different radiative transition processes are achieved under ultraviolet and high‐energy radiation due to the tunable carrier dynamics from the shallow trapped state to the self‐trapped exciton (STE) state.

Colorimetric aptasensor based on self-screened aptamers and cascaded catalytic reaction for the detection of quarantine plant bacteria

Quarantine plant bacteria (QPB) are significant component of invasive alien species that result in substantial economic losses and serious environmental damage. Herein, a colorimetric aptasensor has been proposed based on the sandwich structure and the cascaded catalytic strategy for on-site detecting Xanthomonas hyacinthi, a type of QPB, in natural environments. The self-screened aptamer obtained through SELEX can bind to specific sites on the surface of viable organism with high affinity and specificity, which guarantees the selectivity of aptasensor. As an important part of the aptasensor, MIL-88-NH2(Fe) not only acts as a multifunctional carrier for both aptamers and glucose oxidase, but also catalyzes enzyme-like reaction because of specific surface area, amino and peroxidase-like activity. The present of Xanthomonas hyacinthi can trigger the formation of a sandwich structure and the occurrence of cascade catalytic reaction, enabling the detection with UV–Vis spectra and naked eyes. The proposed aptasensor presents a low detection limit of 2 cfu/mL and a wide linear range of 10 -107 cfu/mL. Compared to traditional detection methods for QPB, the reasonable design, high selectivity and convenience significantly improve the detection efficiency and contribute to environmental protection.

Tidal connectivity modelling in wetlands associated with coastal lagoon of Punta Rasa natural reserve, Argentina

Tidal flows play a crucial role in connecting coastal lagoons to the sea through channels, in this way determining the hydrological dynamics of these environments. The Punta Rasa Natural Reserve (Ramsar site) is located in a transitional zone between the outer limit of the estuary of the Río de la Plata and the open sea. In this work, we study the northernmost lagoon at the end of the spit, which is connected to the sea by a narrow tidal channel. Wetlands are developing at the edges of the lagoon and in lower lying sectors. The aim of this study is to develop a conceptual model that explains the tidal connectivity of the coastal lagoon and to assess how it affects the marsh environments. Detailed topographic surveys were performed using Structure from Motion Multi-View Stereo from a UAV, while sea level data was analyzed using recordings at 20-min intervals over a five-year period. This dataset facilitated an analysis of the frequency of exceedances for threshold values of 0.8, 1.0, 1.2 and 1.4 m. The frequency analysis reveals that the highest exceedances of these thresholds occur during the summer months. When the water level reaches 1 m, the lagoon is fully connected to the sea via the tidal channel, resulting in complete inundation of the low marshland and the margins of the high marshland. At a tidal level of 1.4 m, the high marsh connected to the tidal channel and the coastal lagoon experience flooding. The results obtained in this study provides insights into modelling hydrological connectivity between marshes and the sea, as well as determining the frequency of tidal inundation in each wetland.

Daily and Weekly “High Doses” of Cholecalciferol for the Prevention and Treatment of Vitamin D Deficiency for Obese or Multi-Morbidity and Multi-Treatment Patients Requiring Multi-Drugs—A Narrative Review

Daily vitamin D supplementation using higher than normal dosing (up to the upper limit value) and intermittent (once or twice per week) dosing were studied in patients with increased risk of vitamin D deficiency. Using a PubMed database, a thorough search for published randomized controlled trials and other studies was conducted, and the results were analyzed. This review provides an overview of the use of 7000 IU daily, 30,000 IU per week or twice weekly, and 50,000 IU weekly of vitamin D for obtaining and maintaining 25(OH)D concentrations of at least 30 ng/mL in patients at high risk of vitamin D deficiency. The abovementioned dosages should be considered in adults with obesity, liver disease or malabsorption syndromes, or multi-diseased patients, mainly seniors requiring multi-drug treatment, including drugs affecting vitamin D metabolism. The simple schedules of 7000 IU/day, 30,000 IU/week or twice weekly, and 50,000 IU/week for use by patients with an increased risk of vitamin D deficiency were provided for consideration. Without monitoring of 25(OH)D, daily doses of 7000 IU or intermittent doses of 30,000 IU/week should be considered for a prolonged time as prophylactic or maintenance doses, mainly in obese patients, patients with liver disease and patients with malabsorption syndromes. For the treatment of possible vitamin D deficiency without assessment of 25(OH)D in these groups, intermittent doses of 30,000 IU twice weekly or 50,000 IU per week should be considered for a 6–8-week period only. The higher daily doses or the intermittent doses suggested above are effective, safe and responsive based on patient’s preferences.

Can Stiff Matter Solve the Hubble Tension?

A new form of the mathematical expression for the co-moving volume element of a flat universe with cosmological constant, cold matter, and stiff matter is presented. It is used to determine the constraints from the Planck measurements of the Hubble parameter on the amount of stiff matter in the universe. These constraints are used to investigate whether the presence of stiff matter can solve the Hubble tension. It is found that the Planck measurements lead to an upper bound on the present value of the density parameter of stiff matter ΩS0&lt;5⋅10−23, and that this is too small to solve the Hubble tension. Report. The main objective of this article is to introduce a novel mathematical expression for the co-moving volume element in a flat universe that includes a cosmological constant, cold matter, and stiff matter. This expression is utilized to derive constraints on the amount of stiff matter in the universe based on the Planck measurements of the Hubble parameter. These constraints are then examined to assess whether stiff matter could potentially resolve the Hubble tension. The findings indicate that the Planck measurements impose an upper limit on the current value of the density parameter of stiff matter, ΩS0&lt;5⋅10−23, which is insufficient to resolve the Hubble tension.