Particle Counter Research Articles

DEM simulation of a single screw granulator: The effect of liquid binder on granule properties

The Caleva UK single-screw Variable Density Extruder (VDE) is a continuous powder processing equipment known for spheronization and extrusion. Its suitability for granulation remains uncertain, a common challenge in powder processing industries that deal with granules, pellets, and tablets. This study investigates the VDE's potential for granulation, using 65 µm CaCO3 powder and PEG 4000 as a liquid binder. In order to replicate several experimental setups with varying binder concentrations and liquid-to-solid ratios (L/S) of 0.1 and 0.15, eight DEM simulations were run. Our results indicate that higher binder concentrations yield more consistent products with fewer fines, while lower concentrations result in inconsistent products with increased fines. Low L/S ratios produce fragile, fine-sized products with a broad particle size distribution (PSD). DEM simulations reveal a direct relationship between liquid binder content and contact forces. Analysis of bonds formed, and particle counts in simulations corroborates experimental observations of fines production. Additionally, granule strength appears to be directly proportional to contact force.

Single-particle imaging of nanomedicine entering the brain

Nanomedicine has emerged as a revolutionary strategy of drug delivery. However, fundamentals of the nano-neuro interaction are elusive. In particular, whether nanocarriers can cross the blood-brain barrier (BBB) and release the drug cargo inside the brain, a basic process depicted in numerous books and reviews, remains controversial. Here, we develop an optical method, based on stimulated Raman scattering, for imaging nanocarriers in tissues. Our method achieves a suite of capabilities-single-particle sensitivity, chemical specificity, and particle counting capability. With this method, we visualize individual intact nanocarriers crossing the BBB of mouse brains and quantify the absolute number by particle counting. The fate of nanocarriers after crossing the BBB shows remarkable heterogeneity across multiple scales. With a mouse model of aging, we find that blood-brain transport of nanocarriers decreases with age substantially. This technology would facilitate development of effective therapeutics for brain diseases and clinical translation of nanocarrier-based treatment in general.

Operator-derived particles and falling bacteria in biosafety cabinets

IntroductionTo ensure the sterility of cell products that cannot undergo conventional sterilization processes, it is imperative to establish and maintain a clean room environment, regulated through environmental monitoring, including particle counts. Nevertheless, the impact of particles generated by operators as potential contaminants remains uncertain. Thus, in this study, we conducted an accelerated test to assess the correlation between particles generated by operators and airborne bacteria, utilizing biosafety cabinets within a typical laboratory setting. These biosafety cabinets create a controlled environment with air conditioning and high-efficiency particulate air (HEPA) filters, offering fundamental data relevant to cell production. Materials and methodsWe conducted a simulation followed by real-time experiments involving human operations to explore the quantity of particles, particle sizes, and the percentage of bacteria within these particles. This investigation focused on conditions with heightened particle generation from operators within a biosafety cabinet. The experiment was conducted on operators wearing textile and non-woven dustless clothing within biosafety cabinets. It entailed tapping the upper arms for a duration of 2 min. ResultsObservations under biosafety cabinet-off conditions revealed the presence of various particles and falling bacteria in textile clothing. In contrast, no particles or falling bacteria were detected in operators wearing dustless clothing within biosafety cabinets. Notably, a correlation between 5 μm particles and colony-forming units in textile clothing was identified through this analysis. The ratio of falling bacteria to the total number of particles within the biosafety cabinet was 0.8 ± 0.5 % for textile clothing, while it was significantly lower at 0.04 ± 0.2 % for dustless clothing. ConclusionThis study demonstrated that the number of particles and falling bacteria varied depending on the type of clothing and that quantitative data could be used to identify risks and provide basic data for operator education and evidence-based control methods in aseptic manufacturing areas. Although, this study aims to serve as an accelerated test operating under worst-case conditions, the results need to make sure the study range in general research.

An eco-friendly and ultrasensitive micro-orifice resistance assay for the detection of Listeria monocytogenes based on calcium carbonate signal probes harvested from discarded eggshells

The development of eco-friendly analytical methods for the detection of foodborne pathogens is of great importance for protecting human health and alleviating environmental pressure. Here, we demonstrate that a material (CaCO3 microparticles) prepared from discarded eggshells can be used as signal probes for micro-orifice resistance assay (MORA) and can be combined with ligation-mediated branching hybridization chain reaction (LB-HCR)-based signal-amplification technique (e-LMORA) for high sensitivity detection of Listeria monocytogenes. This strategy used LB-HCR-induced aggregation of streptavidin-modified CaCO3 microparticles, which were recognized by the particle counter for quantitative analysis of the target DNA. Compared with traditional MORA using polystyrene microspheres as signal probes, CaCO3 microparticles prepared from waste eggshells are more environmentally friendly. The combination of DNA-recognition probe, signal probes, and enzyme-free signal-amplification strategy not only reduces the cost synergistically, but also enables the biosensor to attain high sensitivity (limit of detection = 21 CFU/mL) due to its efficient signal amplification.

Plastic and anthropogenic microfiber pollution on exposed sandy beaches in Nova Scotia, Canada

Aim: To investigate the baseline abundance of microplastics on two sandy beaches along an exposed coastline in an understudied region of the Northwest Atlantic. Methods: Sandy sediments were sampled from two beaches along the eastern shore of Nova Scotia, Canada from High, Mid, and Low intertidal positions. Density floatation using a sodium iodide (NaI) solution was used to separate particles from 100 g of sediments in each sample. Particles were characterized by size, shape, and colour, and Fourier transform infrared (FTIR) spectroscopy was conducted for polymer identification. Results: At both beaches, the majority of particles found were small (< 1.4 mm), transparent microfibers. Microplastics were polymers of polyethylene terephthalate (PET), nylon, or alkyds (paints). The mean concentrations at both beaches were similar, at 5.08 ± 3.20 and 5.58 ± 4.52 microplastics per 100 g of sediment. Non-plastic (i.e., natural and semi-synthetic cellulosic) microfibers were up to 19 times more abundant than microplastics, with mean concentrations of 75.9 ± 60.1 and 97.7 ± 87.9 per 100 g sediment. Mean particle counts did not differ significantly across tidal ranges due to their high variability over small spatial scales (10 s of m). Conclusion: Using new investigative tools yielded estimates of microplastic pollution 1-2 orders of magnitude lower than earlier research conducted at these sites, and was generally lower than values reported from other beaches globally. Sources of microfibers were potentially from high recreational use at these sites. Future monitoring could target these sites for time series analysis of microplastic change on exposed sandy beaches.

Beyond Microplastics: Implementation of a Two-Stage Removal Process for Microplastics and Chemical Oxygen Demand in Industrial Wastewater Streams

Wastewater from plastic manufacturing or processing industries is often highly polluted with microplastics (MPs) and high levels of oxidizable organic matter, which results in a high chemical oxygen demand (COD). When industrial wastewater enters wastewater streams, the high microplastic load is a high burden for municipal wastewater treatment plants (WWTPs), as they are not sufficiently removed. To prevent MP from entering the WWTPs, an upstream prevention method is essential. This paper presents a pilot-scale plant study for the removal of MP and COD from industrial wastewater that was tested on-site at a plastic manufacturer in Germany. Eight test phases were performed over 3 months, with each test phase processing 1 m3 wastewater and four treatments. Per test phase, 12 samples were analyzed for 5 parameters: COD, total suspended solids (TSSs), particle count, pH, and turbidity. The results showed an average decrease in MP by 98.26 ± 2.15% measured by TSSs and 97.92 ± 2.31% measured by particle count. This prevents the emission of 1.1 kg MP/m3 water and an estimated 2.7 t MP/year. The COD was reduced efficiently by 94.3 ± 8.9%. Besides MP and COD, this treatment allows reuse of water and agglomerates, resulting in a reduction in the CO2 footprint.

Solid Particle Number (SPN) Portable Emission Measurement Systems (PEMS) for Heavy-Duty Applications

A heavy-duty engine is homologated in a test cell. However, starting with Euro VI regulation, the in-service conformity is controlled with the engine installed in the vehicle using portable emission measurement systems (PEMS). In Europe, the application of solid particle number (SPN) PEMS started in 2021 for compression ignition (diesel) vehicles and in 2023 for positive ignition vehicles, thus including those operating with compressed natural gas (CNG). Even though today only particles with sizes > 23 nm are regulated, the Euro 7 proposal includes particles > 10 nm. There are not many studies on the accuracy of the SPN PEMS, especially for heavy-duty applications. In this study, PEMS measuring > 23 and >10 nm from two instrument manufacturers were compared with laboratory-grade instruments. The particle detector of one PEMS was a condensation particle counter (CPC), and of the other a the diffusion charger (DC). The results showed the robustness and good accuracy (40% or 1 × 1011 #/kWh) of the PEMS for ambient temperatures from −7 °C to 35 °C, active regeneration events, different fuels (Diesel B7, HVO, and CNG), different test cycles, cold start or hot engine operations, and high exhaust gas humidity content. Nevertheless, for the DC-based PEMS, sensitivity to pre-charged urea particles was identified, and for the CPC-based PEMS, sensitivity to pressure changes with one vehicle was nnoticed. Nevertheless, the results of this study confirm that the PEMS are accurate enough to measure even the stricter Euro 7 limits.

Evaluating Clinical Safety and Analytical Impact of Subvisible Silicone Oil Particles in Biopharmaceutical Products

Silicone oil is a commonly used lubricant in pre-filled syringes (PFSs) and can migrate over time into solution in the form of silicone oil particles (SiOPs). The presence of these SiOPs can result in elevated subvisible particle counts in PFS drug products compared to other drug presentations such as vials or cartridges. Their presence in products presents analytical challenges as they complicate quantitation and characterization of other types of subvisible particles in solution. Previous studies have suggested that they can potentially act as adjuvant resulting in potential safety risks for patients. In this paper we present several analytical case studies describing the impact of the presence of SiOPs in biotherapeutics on the analysis of the drug as well as clinical case studies examining the effect of SiOPs on patient safety. The analytical case studies demonstrate that orthogonal techniques, especially flow imaging, can help differentiate SiOPs from other types of particulate matter. The clinical case studies showed no difference in the observed patient safety profile across multiple drugs, patient populations, and routes of administration, indicating that the presence of SiOPs does not impact patient safety.

Transradial carotid artery stenting using double layer micromesh stent and novel post-dilation balloon with integrated embolic protection

ObjectivesThe highest rate of embolization during carotid artery stenting occurs during post-dilation. We evaluated the ability of the Paladin system (Contego Medical, Raleigh, NC), a novel PTA balloon with an integrated 40-ɥm pore filter, to collect microemboli that may pass into the cerebral circulation when used during post-dilation. Methods25 symptomatic patients underwent transradial CAS using the Paladin system in conjunction with the Roadsaver (Terumo Corporation, Tokyo, Japan) micromesh stent. No additional embolic protection was used. The Paladin filters were collected following the procedure and preserved in formalin for histological analysis. The contents were evaluated for particle count and size. Subjects were followed for 30 days and evaluated for major cardiac adverse events (death, stroke and MI). Secondary endpoints included procedure success, device success, access site complications according to EASY score classification, major vascular or ischemic complications at follow up and in-stent restenosis rate evaluated with duplex ultrasound. ResultsMean age of patients was 68,5 years. Type 2 aortic arch was present in 77 % of patients and type 1 and type 3 in 12 % and 11 % of patients respectively. Procedural and device success was obtained in all cases without complications. The 30-day MAE rate was 0 %. Twenty-three filters underwent histological analysis. Microscopic debris was present in 100 % of filters, and 75 % of particles were less than 100ɥm in size. The mean number of particles per filter was 3352 ± 1567 (IQR 4300–2343), and the mean number of particles between 40-100ɥm per filter was 2499 ± 1240 (IQR 3227–1575). ConclusionCAS through radial approach can be safely and effectively performed using the IEP technology Paladin device and double-layer micromesh Roadsaver stent. This strategy can simplify the procedure and decrease peri-procedural complications and procedural time.

Effect of cuttings particle content on the tribological behavior of Fe/DLC at casing and drill pipe joints: A molecular dynamics study

The presence of cuttings in the drilling fluid can exacerbate the wear of drill pipe joints and casing. Diamond-like carbon (DLC) films have ultra-low friction coefficients and high wear resistance, which have excellent research prospects in reducing the wear between drill pipe joints and casing. To investigate the impact of varying particle counts at the interface between Fe bulk and DLC film, this work builds a pertinent molecular dynamics model. The results show that the interfacial friction increases with increasing particle content, which leads to more severe abrasive wear on the Fe bulk and prevents the amorphous structure atoms in the Fe bulk from recovering to a body-centered cubic crystal structure. On the contrary, the DLC film is difficult to be affected by the particle motion because of its good tribological properties. Simultaneously, more silica particles reduce the space for the movement of water molecules and ultimately weaken the lubrication ability of water molecules.

CHART: a novel system for detector evaluation against toxic chemical aerosols

Concern over the possibility of deliberate dispersion of chemical warfare agents and highly toxic pharmaceutical based agents as persistent aerosols has raised the need for experimental assessment of current and future defensive capabilities of armed forces and law enforcement agencies. Therefor we herewith present the design, realization and validation of the Chemical Hot Aerosol Research Tool (CHART) as a validated and safe experimental set-up for performance evaluation of chemical detection and identification equipment against chemical warfare agents and other highly toxic compounds. In the CHART liquid and solid compounds in solution or suspension are being dispersed as aerosols in a nebulization chamber. A broad dynamic particle size range can be generated, including particles known to be able to reach the lower respiratory tract. The aerosol generated is presented to the detection system-under-test while being monitored and characterized in real-time, using an optical particle counter and a time-of-flight aerosol analyzer, respectively. Additionally, the chemical composition of the aerosol is ex situ measured by analytical chemical methods. Evidently, in the design of the CHART significant emphasis was placed on laboratory safety and containment of toxic chemicals. The CHART presented in this paper has proven to be an indispensable experimental tool to study detectors and fieldable identification equipment against toxic chemical aerosols.

Water–air transfer rates of microplastic particles through bubble bursting as a function of particle size

Microplastic (MP) particles can be ejected into the air by jet drops when gas bubbles burst at water surfaces. For a qualitative and quantitative understanding of this transport mechanism from the hydrosphere to the atmosphere, we studied the transfer of MP due to bubble bursting at the air–water interface in laboratory experiments. Gas bubbles were produced with filtered air that was pushed through a stainless-steel frit at two different volume flow rates in a glass flask filled with polystyrene (PS) particles of six different diameters (0.35 µm, 0.5 µm, 0.75 µm, 1 µm, 1.5 µm, 2 µm) suspended in deionized water. Airborne PS particle concentrations were measured by an optical particle counter. Additionally, size and volume of the bursting bubbles and the resulting jet droplets were analyzed with a camera. Depending on the volume flow rates, bubble bursting rates from 688 s−1 to 1176 s−1 and mean diameters of the bursting bubbles from 0.76 mm to 0.81 mm were observed. The mean diameters of the top jet drops were estimated to be between 0.10 mm and 0.11 mm. The measured number of jet droplets ranged from 2092 s−1 to 2391 s−1. For particle diameters from 0.35 µm – 2.0 µm, the airborne MP particle concentrations ranged from 4.2 l−1 to 348 l−1. We determined size-dependent transfer factors for the water–air transfer and found a maximum for 1 µm particles. For MP particles up to 1 µm diameter, the particle concentration in the jet droplets was enhanced compared to the bulk water concentration, indicating an enrichment of MP particles at the water–air-interface of bubbles.

In-vehicle ultrafine and fine particulate matter exposures during commuting in a South Asian megacity: Dhaka, Bangladesh

We measured ultrafine particle number concentration (PNC) and fine particulate matter mass concentration (PM2.5) levels in public buses and private cars under three conditions: windows open, windows closed with air recirculation off, and windows closed with air recirculation on in Dhaka, Bangladesh—an extremely polluted megacity in South Asia. We collected measurements on ∼10 repeated round trips on unique days for each selected transportation mode, covering various routes that spanned multiple arterial roads over several months (January to March 2020 and November to December 2020) and different times of the day to account for the variability in traffic and meteorological conditions. We used a condensation particle counter (CPC) to measure PNC and a PurpleAir sensor to measure PM2.5 mass concentrations. We applied corrections to the raw data and analyzed quality-assured data to investigate exposure differences across modes, pollutants, locations, and times. Public buses and private cars with open windows had mean PNC levels of 112,000 # cm−3 and 117,000 # cm−3, approximately 5–6 times higher than the mean urban background level of around 20,000 # cm−3. PM2.5 levels in these vehicles were approximately ∼100 μg m−3, about 20% higher than the urban background PM2.5 level of 85 μg m−3. With closed windows and air recirculation off, concentrations were 15% lower for PNC and 10% lower for PM2.5. Under closing windows and keeping air recirculation on, mean PNC and PM2.5 levels were 60,000 # cm−3 and 70 μg m−3, respectively, representing a 50% reduction for PNC and a 30% reduction for PM2.5 compared to open windows. Our findings suggest that commuters in public buses and private cars with open windows have higher and similar exposure levels, whereas those commute in private cars with closed windows and air recirculation on have lower exposure levels.

Drug compatibility with various closed intravenous infusion containers.

Objective: The aim was to systematically compare the drug compatibility with various closed intravenous (i.v.) infusion containers, to provide a reference for selecting a relatively superior infusion container and improve the medication safety for patients in clinical practice. Methods: The compatibility of four commonly used clinical injections (ceftazidime, pantoprazole sodium, ambroxol hydrochloride, edaravone) with three representative closed i. v. infusion containers (non-PVC infusion bags, upright polypropylene infusion bags, inner sealed polypropylene infusion bags) prefilled with infusion fluids (0.9% sodium chloride or 5% dextrose) in the Chinese market were investigated in this study. The particle counts of both infusion fluids and diluted chemical injections by infusion fluids in various infusion containers were determined by the light obscuration method. At 0, 2 and 6h after four injections following dilution with infusion fluids in each container, the pH of the solutions was detected, and the physical properties were examined by visual inspection. Meanwhile, the drug concentrations were assessed by high performance liquid chromatography (HPLC). Results: As for either infusion fluids or diluted injections by infusion fluids, the particle counts in non-PVC infusion bags were significantly greater than those in the other two bags under some circumstances. The particle counts in diluted injections by infusion fluids increased dramatically compared with those in infusion fluids in all infusion containers, especially for the small-size particles. But pH, physical properties and drug concentrations of diluted infusion solutions in all infusion containers remained nearly unchanged over the test period. Conclusion: Closed i. v. infusion containers included in this study are all well-compatible with four injections. Moreover, the closed infusion containers produced by Chinese manufacturers have met the international quality standard. Particularly, the intravenous admixture preparation process needs to be optimized to reduce the overall particulate contaminants.

Analysis of aerosol generation during Er:YAG laser-assisted caries treatment: A randomized clinical trial.

Maintaining biosafety in dental practice involves the effective elimination of aerosols produced during dental treatment. To assess the quantity of aerosols and aerobic bacteria in the air during the treatment of caries. The study involved 60 patients with a total of 60 molar teeth (n = 60) in the mandible who were divided into 2 groups based on caries treatment method. Group 1 (G1, n = 30) received treatment with a conventional dental turbine (W&H Synea TA-98LC; W&H, Burmoos, Austria), while group 2 (G2, n = 30) underwent treatment with an Er:YAG (erbium-doped yttrium aluminium garnet) laser (LightWalker, Fotona, Slovenia). Measurements of aerosol particles between 0.3 Ęm and 10.0 Ęm near the operatorfs mouth were taken using the PC200 laser particle counter (Trotec GmbH, Schwerin, Germany). The number of aerobic bacteria in the air was determined using 60 Petri plates with a microbiological medium (Columbia agar with 5% sheep blood) and the sedimentation method. A control group (G3) was established to measure initial aerosol levels and initial total number of bacteria colony-forming units (CFUs) before each treatment. In G1 (dental turbine), the median value of aerosol particles was 57,021 (42,564.67,568), while in G2 (Er:YAG laser), it was significantly lower at 33,318 (28,463.35,484) (p < 0.001). The median total bacteria count per cubic meter of air in G1 (conventional dental turbine + high volume evacuator (HVE)), G2 (Er:YAG laser + HVE) and G3 (control group before caries treatment) were 734 (420.988), 158 (96.288) and 48 (32.74), respectively, with a statistically significant difference between the groups (p < 0.001). The use of Er:YAG laser during caries treatment resulted in a 41.6% reduction in aerosol amounts and a 78.5% decrease in the total bacterial count (TBC) compared to treatment with a dental turbine.

IR-finite thermal acceleration radiation

A charge accelerating in a straight line following the Schwarzschild–Planck moving mirror motion emits thermal radiation for a finite period. Such a mirror motion demonstrates quantum purity and serves as a direct analogy of a black hole with unitary evolution and complete evaporation. Extending the analog to classical electron motion, we derive the emission spectrum, power radiated, and finite total energy and particle count, with particular attention to the thermal radiation limit. This potentially opens the possibility of a laboratory analog of black hole evaporation.

Differences in ultrasonic cavitation damage between new and used engine coolants with varying time in operation

This study investigates the cavitation erosion performance of heavy-duty engine coolants before and after operation in trucks using an ultrasonic test rig based on ASTM G32. Fresh coolants with 35% and 50% v/v glycol were compared with used coolants. One coolant was obtained from a gasoline-fueled vehicle with a mileage of 27000 km, and two from diesel-fueled vehicles with mileages of 16000 and 180 000 km, respectively. Surface tension and boiling point at atmospheric pressure were measured, a chemical analysis was carried out, and suspended particles were quantified by dynamic image analysis. The results showed that the used coolants caused a lower mass loss in ultrasonic cavitation testing than the fresh ones, and that they had higher boiling points, lower pH and a higher number of suspended particles, especially of those smaller than 30μm. Surface tension was higher for the used coolants from Diesel engines.The lower mass loss caused by all three used coolants can be attributed mainly to their high boiling point and high particle count. The presence of particles is believed to promote the heterogeneous nucleation of smaller, more stable bubbles, which may protect the exposed surface by shockwave absorption and microjet deflection. Some dissolved ions in the used coolants may help reduce their aggressivity by inhibiting bubble coalescence, reducing bubble collapse energy, despite increasing surface tension. Surface tension has complex interactions with the solutes, particles and bubble formation and cannot, in isolation, explain the differences in performance of the coolants.

Moving toward point-of-care surgery in Ukraine: testing an ultra-portable operating room in an active war zone.

In conflict zones, providers may have to decide between delaying time-sensitive surgeries or performing operative interventions in the field, potentially subjecting patients to significant infection risks. We conducted a single-arm crossover study to assess the feasibility of using an ultraportable operating room (U-OR) for surgical procedures on a porcine cadaver abdominal traumatic injury model in an active war zone. We enrolled participants from an ASSET-type course designed to train Ukrainian surgeons before deployment to active conflict zones. They performed three standardized consecutive abdominal surgical procedures (liver, kidney, and small bowel injury repair) with and without the U-OR. Primary outcomes included surgical procedurecompletion rate, procedure time, and airborne particle count at the start of surgery. Secondary survey-based outcomes assessed surgery task load index (SURG-TLX) and perceived operative factors. Fourteen surgeons performed 76 surgical procedures (38 with the U-OR, 38 without the U-OR). The completion rate for each surgical procedure was 100% in both groups. While the procedure time for the liver injury repair did not differ significantly between the two groups, the use of the U-OR was associated with a longer time for kidney (155 vs. 56s, p = 0.002), and small bowel (220 vs. 103s, p = 0.004) injury repair. The average airborne particle count within the U-OR was substantially lower compared to outside the U-OR (6,753,852 vs. 232,282 n/m3, p < 0.001). There was no statistically significant difference in SURG-TLX for procedures performed with and without the U-OR. The use of the U-OR did not affect the procedure completion rate or SURG-TLX. However, there was a marked difference in airborne particle counts between inside and outside the U-OR during surgery. These preliminary findings indicate the potential feasibility of using a U-OR to perform abdominal damage-control surgical procedures in austere settings.

Development of a radiochemical test procedure for the separation of aerosol-borne allergens

An innovative radiochemical method has been developed to determine the filtration efficiency of HEPA filters for biological nanoparticles. The setup based on EN 1822, for flat sheet media, is up to 40 times more sensitive for a single particle than methods based on particle counting, even for low particle concentrations. To achieve such a high sensitivity the radioactive tracer technique is utilised using a solution of bovine serum albumin (BSA) labelled with radioactive iodine (131I). With the aid of an aerosol generator, this solution is nebulised into nanoparticles of a defined size, which are then passed to the test filter via a compressed air flow. On the raw and clean gas side of the test filter, the 131I is measured with two NaI(Tl) detectors. By balancing the measurement data with each other, the filter efficiency can be determined. Initially, the setup has been validated with current particle counting methods, according to EN 1822, to ensure its functionality. Subsequently, the first experiments with radiolabelled nanoparticles gave promising results, as will be shown below. Further experiments also yielded information about filter clogging and its influence on the filter efficiency.

Rancang Bangun Particle Counter untuk Monitoring Konsentrasi PM1, PM2.5 dan PM10 di Udara Berbasis IoT

Poor air quality is a serious health and environmental issue. Microscopic particles such as PM1, PM2.5, and PM10 cause respiratory disorders and other health problems. Therefore, accurate and continuous air quality monitoring is crucial to mitigate the impacts of air pollution. This research aims to design an Internet of Things (IoT)--based particle counter capable of real-time air quality monitoring and reporting via an online platform. The system utilizes a PMS5003 sensor to measure PM1, PM2.5, and PM10 concentrations precisely. Data from the sensor is processed by an ESP8266 microcontroller connected to the internet, enabling direct data transmission to an online platform for further analysis and visualization. Testing is done by creating a 1x1x1 meter testing chamber to simulate various environmental conditions and validate the device's performance. Results show that the particle counter provides accurate data, with an error rate of less than 10% compared to standard devices. The device demonstrates reliable operation across different environmental conditions, showcasing its robustness in practical applications. This IoT-based particle counter offers an innovative solution for effective and efficient air quality monitoring. It is expected to significantly contribute to human health protection efforts and minimize the adverse environmental impacts of air pollution.