Swab Sampling Techniques Research Articles

Flexible SERS sensor based on the photodecoration of Au-NPs on Co3O4 NWs/carbon fiber cloth for the ultrasensitive detection of methylene blue in the curved fish surfaces

BackgroundDevelopment of flexible platform via the surface-enhanced Raman spectroscopy (SERS) technique has gained enormous attention as a low-cost and portable substrate for a wide range application. In particular, the fabrication of semiconductors and tuning their surface morphologies with plasmonic nanoparticles are considered to be a fascinating strategy to create numerous hotspots to yield superior SERS enhancement. ResultsThis work involved fabricating a flexible SERS active substrate using the carbon fiber cloth (CFC), which is hydrothermally grown with cobalt oxide nanowires (Co3O4 NWs) and photodecorated with plasmonic gold nanoparticles (Au-NPs) for the ultrasensitive detection of organic dye, methylene blue (MB). The proposed substrate exhibits high enhancement factor (4.5 × 1010), low limit of detection (1.42 × 10−10 M), good uniformity (6.27 %), superior reproducibility (6.30 %) and demonstrate an excellent mechanical strength up to 40 cycles towards the MB detection. The residues of the MB are directly detected on the fish surfaces by adopting a facile swab-sampling technique. Additionally, the proposed flexible SERS sensor exhibit a successful photodegradation of MB at 90 min under UVC light irradiation. Significance and noveltyThe proposed flexible SERS methodology for detecting MB in the curved surfaces exhibited a superior SERS enhancement owing to the synergistic effect raised from the Co3O4 NWs (chemical enhancement) and Au NPs (electromagnetic enhancement). These findings indicate that the CFC-based flexible SERS sensor is a promising candidate for detecting various organic pollutants in real-time and on non-planar surfaces.

Intermediate Cluster Disinfection: Which Disinfection Solution Is Most Effective on Milking Liners? A Comparison of Microorganism Reduction on Liner Inner Surfaces Using Quantitative Swab Sampling Technique.

During machine milking, pathogenic microorganisms can be transmitted from cow to cow through liners. Therefore, in Germany, a spray method for the intermediate disinfection of the milking cluster is often used for prevention. This method of cluster disinfection is easy to perform, requires little time and no extra materials, and the disinfection solution is safe from outside contamination in the spray bottle. Since no data on a systematic efficacy trial are available, the aim of this study was to determine the microbial reduction effect of intermediate disinfection. Therefore, laboratory and field trials were conducted. In both trials, two sprays of 0.85 mL per burst of different disinfectant solutions were sprayed into the contaminated liners. For sampling, a quantitative swabbing method using a modified wet-dry swab (WDS) technique based on DIN 10113-1: 1997-07 was applied. Thus, the effectiveness of disinfectants based on Peracetic Acid, Hydrogen Peroxide and Plasma-Activated Buffered Solution (PABS) was compared. In the laboratory trial, the inner surfaces of liners were contaminated with pure cultures of Escherichia (E.) coli, Staphylococcus (S.) aureus, Streptococcus (Sc.) uberis and Sc. agalactiae. The disinfection of the contaminated liners with the disinfectants resulted in a significant reduction in bacteria with values averaging 1 log for E. coli, 0.7 log for S. aureus, 0.7 log for Sc. uberis and 0.8 log for Sc. agalactiae. The highest reduction was obtained for contamination with E. coli (1.3 log) and Sc. uberis (0.8 log) when PABS was applied and for contamination with S. aureus (1.1 log) and Sc. agalactiae (1 log) when Peracetic Acid Solution (PAS) was used. Treatment with sterile water only led to an average reduction of 0.4 log. In the field trial, after the milking of 575 cows, the liners were disinfected and the total microorganism count from the liner surface was performed. The reduction was measured against an untreated liner within the cluster. Although a reduction in microorganisms was achieved in the field trial, it was not significant. When using PAS, a log reduction of 0.3 was achieved; when using PABS, a log reduction of 0.2 was obtained. The difference between the two disinfection methods was also not significant. Treatment with sterile water only led to a reduction of 0.1 log. The results show that spray disinfection under these circumstances does result in a reduction in the bacteria on the milking liner surface, but for effective disinfection a higher reduction would be preferred.

Prevalence and Seasonal Variation of Different Respiratory Pathogens in Post-Weaned Pigs with Signs of Clinical Respiratory Disease Using a Tracheobronchial Swab Sampling Technique: An Update from Belgium and the Netherlands

Besides Mycoplasma hyopneumoniae (M. hyopneumoniae), many other viruses and bacteria can concurrently be present in pigs. These pathogens can provoke clinical signs, known as porcine respiratory disease complex (PRDC). A sampling technique on live animals, namely tracheobronchial swab (TBS) sampling, was applied to detect the major PRDC pathogens in pigs using PCR. The objective was to determine prevalence of different PRDC pathogens and their seasonal variations in Belgium and the Netherlands. A total of 600 pig farms and 9,000 post-weaned piglets were sampled using TBS over a 4-year period. TBS samples were analyzed using mPCR and results were categorized and analyzed according to the season of sampling. In Belgium, 53.8% of the sampled farms were PRRSV-positive, followed by M. hyopneumoniae (48.8%) and IAV-S (40.3%), whereas only 20.6% of the farms were detected PCV-2- positive. In the Netherlands, a similar percentage of farms were detected positive for PRRSV (51.4%) and IAV-S (49.1%), whereas a lower percentage of farms was M. hyopneumoniae-positive (32.4%) and only 8.0% was detected PCV-2-positive. Combined infections consisted of M. hyopneumoniae - PRRSV, PRRSV - IAV-S, and M. hyopneumoniae - PRRSV - IAV-S in both countries. In Belgium, the combination of M. hyopneumoniae - PRRSV - PCV-2 also had a relevant prevalence. For all analyzed PRDC pathogens, clear variations among different seasons could be detected. In conclusion, the present study showed that many respiratory pathogens are present during the post-weaning period, which may complicate the clinical picture of respiratory diseases, and their prevalence may vary among seasons.

Prevalence and Seasonal Variation of Different Respiratory Pathogens in Post-Weaned Pigs with Signs of Clinical Respiratory Disease Using a Tracheobronchial Swab Sampling Technique: An Update from Belgium and the Netherlands

Besides Mycoplasma hyopneumoniae (M. hyopneumoniae), many other viruses and bacteria can concurrently be present in pigs. These pathogens can provoke clinical signs, known as porcine respiratory disease complex (PRDC). A sampling technique on live animals, namely tracheobronchial swab (TBS) sampling, was applied to detect the major PRDC pathogens in pigs using PCR. The objective was to determine prevalence of different PRDC pathogens and their seasonal variations in Belgium and the Netherlands. A total of 600 pig farms and 9,000 post-weaned piglets were sampled using TBS over a 4-year period. TBS samples were analyzed using mPCR and results were categorized and analyzed according to the season of sampling. In Belgium, 53.8% of the sampled farms were PRRSV-positive, followed by M. hyopneumoniae (48.8%) and IAV-S (40.3%), whereas only 20.6% of the farms were detected PCV-2- positive. In the Netherlands, a similar percentage of farms were detected positive for PRRSV (51.4%) and IAV-S (49.1%), whereas a lower percentage of farms was M. hyopneumoniae-positive (32.4%) and only 8.0% was detected PCV-2-positive. Combined infections consisted of M. hyopneumoniae - PRRSV, PRRSV - IAV-S, and M. hyopneumoniae - PRRSV - IAV-S in both countries. In Belgium, the combination of M. hyopneumoniae - PRRSV - PCV-2 also had a relevant prevalence. For all analyzed PRDC pathogens, clear variations among different seasons could be detected. In conclusion, the present study showed that many respiratory pathogens are present during the post-weaning period, which may complicate the clinical picture of respiratory diseases, and their prevalence may vary among seasons.

Seasonal Variation in Prevalence of Mycoplasma hyopneumoniae and Other Respiratory Pathogens in Peri-Weaned, Post-Weaned, and Fattening Pigs with Clinical Signs of Respiratory Diseases in Belgian and Dutch Pig Herds, Using a Tracheobronchial Swab Sampling Technique, and Their Associations with Local Weather Conditions.

Besides Mycoplasma hyopneumoniae (M. hyopneumoniae), many other viruses and bacteria can concurrently be present in pigs. These pathogens can provoke clinical signs, known as porcine respiratory disease complex (PRDC). A sampling technique on live animals, namely tracheobronchial swab (TBS) sampling, was applied to detect different PRDC pathogens in pigs using PCR. The objective was to determine prevalence of different PRDC pathogens and their variations during different seasons, including correlations with local weather conditions. A total of 974 pig farms and 22,266 pigs were sampled using TBS over a 5-year period. TBS samples were analyzed using mPCR and results were categorized and analyzed according to the season of sampling and local weather data. In samples of peri-weaned and post-weaned piglets, influenza A virus in swine (IAV-S), porcine reproductive and respiratory syndrome virus—European strain (PRRSV1), and M. hyopneumoniae were found as predominant pathogens. In fattening pigs, M. hyopneumoniae, porcine circovirus type 2 (PCV-2) and PRRSV1 were predominant pathogens. Pathogen prevalence in post-weaned and finishing pigs was highest during winter, except for IAV-S and A. pleuropneumoniae, which were more prevalent during autumn. Associations between prevalence of several PRDC pathogens, i.e., M. hyopneumoniae, PCV-2 and PRRSV, and specific weather conditions could be demonstrated. In conclusion, the present study showed that many respiratory pathogens are present during the peri-weaning, post-weaning, and fattening periods, which may complicate the clinical picture of respiratory diseases. Interactions between PRDC pathogens and local weather conditions over the 5-year study period were demonstrated.

Molecular diagnosis of scabies using a novel probe-based polymerase chain reaction assay targeting high-copy number repetitive sequences in the Sarcoptes scabiei genome.

The suboptimal sensitivity and specificity of available diagnostic methods for scabies hampers clinical management, trials of new therapies and epidemiologic studies. Additionally, parasitologic diagnosis by microscopic examination of skin scrapings requires sample collection with a sharp scalpel blade, causing discomfort to patients and difficulty in children. Polymerase chain reaction (PCR)-based diagnostic assays, combined with non-invasive sampling methods, represent an attractive approach. In this study, we aimed to develop a real-time probe-based PCR test for scabies, test a non-invasive sampling method and evaluate its diagnostic performance in two clinical settings. High copy-number repetitive DNA elements were identified in draft Sarcoptes scabiei genome sequences and used as assay targets for diagnostic PCR. Two suitable repetitive DNA sequences, a 375 base pair microsatellite (SSR5) and a 606 base pair long tandem repeat (SSR6), were identified. Diagnostic sensitivity and specificity were tested using relevant positive and negative control materials and compared to a published assay targeting the mitochondrial cox1 gene. Both assays were positive at a 1:100 dilution of DNA from a single mite; no amplification was observed in DNA from samples from 19 patients with other skin conditions nor from house dust, sheep or dog mites, head and body lice or from six common skin bacterial and fungal species. Moderate sensitivity of the assays was achieved in a pilot study, detecting 5/7 (71.4% [95% CI: 29.0% - 96.3%]) of clinically diagnosed untreated scabies patients). Greater sensitivity was observed in samples collected by FLOQ swabs compared to skin scrapings. This newly developed qPCR assay, combined with the use of an alternative non-invasive swab sampling technique offers the possibility of enhanced diagnosis of scabies. Further studies will be required to better define the diagnostic performance of these tests.

P193 Audit of cough swab sampling techniques in children with cystic fibrosis

P193 Audit of cough swab sampling techniques in children with cystic fibrosis

Validasi Metode Analisis Residu Mometasone furoate dan CIP100 Setelah Proses Pembersihan Peralatan Produksi di Industri Farmasi “XYZ”

In this study, the HPLC and Total Organic Carbon (TOC) analysis methods have been developed and validated for the determination of the amount of Mometasone furoate and CIP100 residues on the surface of production equipment and to confirm the efficiency of the cleaning procedure. Mometasone furoate and CIP100 have been chosen based on the worst case assessment approach. The limit of mometasone furoate contamination that has been determined is 100 ug/swab and the specified limit of CIP100 contamination is 100 ug/swab which should not be exceeded during sequential cleaning of the equipment. Mometasone furoate shows good linearity in the range 0.1-1.0 ppm for the HPLC method and CIP100 2.0-10.0 ppm for TOC Analysis. The percentage of recovery from stainless steel plates using swab sampling techniques was found in the limits of 95.12% and 99.93% respectively in the HPLC and TOC methods. Both methods are simple, inexpensive, short analysis time and high sensitivity for quantitative determination of Mometasone furoate and CIP100 on the surface of manufacturing equipment well below the contamination limit. The validated method meets the requirements for demonstration of the validation of residual cleaning of mometasone furoate and CIP100 on the surface of production equipment

SERS-based rapid assay for sensitive detection of Group A Streptococcus by evaluation of the swab sampling technique.

Beta-hemolytic, Group A Streptococcus pyogenes (GAS) is a life-threating pathogen and the reason for prominent disease, pharyngitis. The conventional analysis of GAS, gold standard, takes 48 hours and the related rapid tests lack in accuracy and sensitivity. In this study, firstly, the efficiency of swab sampling, which is a must in the GAS detection, was discussed with the proposed surface-enhanced Raman spectroscopy (SERS)-based batch assay and each step was controlled by the plate-counting method. Secondly, SERS-based lateral flow immunoassay (LFIA) test strips were constructed and the variation in the SERS intensity of 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) was observed. Thus, a linear correlation was found with a R2 value of 0.9926 and the LOD was calculated to be 0.2 CFU mL-1 of GAS which could be counted as one cell. The combination of the gold standard with the LFIA-SERS technique enabled the fast and accurate pathogen detection. In addition, GAS was quantified with paper-based test strips up to 100 CFU ml-1 level of bacteria for the first time without any interference. Besides, this study was featured with the discussion of the whole cell and pretreated cell detection of pathogens with LFIAs. Therefore, this work enlightens the points that have never been discussed on pathogen detection with paper-based platforms.

Sampling And Identifying Of Mould In The Library Building

Despite the growing concern over mould and fungi infestations on library building, little has been reported in the literature on the development of an objective tool and criteria for measuring and characterising the mould and fungi. In this paper, an objective based approach to mould and fungi growth assessment using various sampling techniques and its identification using microscopic observation are proposed. This study involved three library buildings of Higher Institution Educational in Malaysia for data collection purpose and study of mould growth. The mould sampling of three libraries was collected using Coriolis air sampler, settling plate air sampling using Malt Extract Agar (MEA), IAQ MOLD Alexeter IAQ-Pro Asp/Pen® Test and swab sampling techniques. The IAQ MOLD Alexeter IAQ-Pro Asp/Pen® Test and traditional method technique identified various mould species immediately on the site, and the microscopic observation identifies common types of the mould such as Aspergillus, Penicillium and Stachybotrys’s. The sample size and particular characteristics of each library will result in the mould growth pattern and finding.

Clinical forensic sample collection techniques following consensual intercourse in volunteers – Cervical canal brush compared to conventional swabs

The purpose of the research was to evaluate gynecological evidence collection techniques; the benefit of cervical canal brush sample compared to vaginal fornix and cervical swab samples and the time frame for detecting Y-chromosomal material QiAmp DNA Mini Kit® and Quantifiler Y Human Male DNA Quantification Kit® in adult volunteers following consensual intercourse.Eighty-four adult female volunteers following consensual intercourse were recruited for the study. By combining all sample collecting techniques, 81.0% of the volunteers were Y-DNA positive. Up to 60 h the conventional swab sampling techniques detected more Y-DNA positive samples when compared to the brush technique. However, after 60 h, the cervical canal brush sample technique showed its benefit by detecting 27.3% (6/22) of Y-DNA positive samples, which were Y-DNA negative in both conventional swab sampling techniques. By combining swab and brush techniques, 75% of the volunteers were still Y-DNA positive in 72–144 post-coital hours. The rate of measurable Y-DNA decreased approximately 3% per hour. Despite reported consensual intercourse, 6.8% (3/44) of volunteers were Y-DNA negative within 48 h. Y-DNA was not detected after 144 post-coital hours (6 days).In conclusion, the brush as a forensic evidence collection method may provide additional biological trace evidence from the cervical canal, although the best biological trace evidence collection can be obtained by combining all three sampling techniques. The time frame for gynecological forensic evidence sample collection should be considered to be at least a week if sexual violence is suspected.

Boot swabs to collect environmental samples from common locations in dairy herds for Mycobacterium avium ssp. paratuberculosis (MAP) detection

The aim of the present study was the examination of the boot swab sampling technique for the collection of environmental material in order to identify Mycobacterium avium ssp. paratuberculosis (MAP)-infected herds. Eight dairy herds were included into the study. Four of them had a well-known history of MAP-infection from a herd surveillance programme conducted since 2006. Cows in these herds were repeatedly tested positive in Pourquier® MAP-ELISA (Pourquier, Montepellier, France); in some MAP could be isolated in individual faecal culture despite that symptoms of paratuberculosis were never reported. In four presumably negative herds nearly all cows were repeatedly tested serologically negative for MAP. The pathogen was never isolated from faecal samples of cows by culture. The study was initiated with the aim of standardising environmental samples as a herd diagnostics, in which overall 130 pairs of boot swab samples from the cows' surroundings were taken In 58 of 64 swab samples (90·6%) from confirmed MAP-infected herds the organism could be isolated by mycobacterial culture of the boot swab. Contrarily, in 66 samples from presumably MAP-negative herds only one swab was positive (1·5%). The utilisation of boot swabs as a standardised technique for environmental sampling offers an effective and inexpensive tool for identifying herds infected with MAP. This is the first report of using boot swabs for the collection of environmental samples for MAP- detection in cattle herds. This easy to perform technique enables the economical detection of MAP herd status.

Efficiency of four sampling methods used to detect two common nosocomial pathogens on textiles

Detecting microorganisms on textiles is useful for many purposes, for example to determine the bioburden before laundering, assess the reduction in bacterial counts in connection with various laundry processes, or trace transfer routes in infection control investigations. Therefore a validated, reproducible and rational method is needed. For sampling microorganisms on textile surfaces the most commonly used method is the contact plate method using RODAC plates, first described by Hall and Hartnett followed by the swab sampling technique. Both methods can only capture microorganisms on the surface of the textiles while microorganisms that have penetrated into the deeper structure of the material will not be detected. In our research the contact plate method and the swabbing technique were compared with two wash-off methods. For the first wash-off method the destructive elution method was used, where microorganisms were eluted from the fabrics by shaking the fabrics for a certain time in an elution medium. For the fourth sampling method a nondestructive method that included a compact test device called Morapex® was used, which is based on forced desorption by pressing the microorganisms through the fabric without destroying the fabric. In our research, two types of microorganisms were included ( Klebsiella pneumoniae and Staphylococcus aureus) that cause common nosocomial infections. The aim of this study was to compare the efficiency of the four sampling methods for detecting microorganisms on textiles and to determine the lowest concentration, which can still be detected. The percentage of microorganisms that were detected by both elution methods was substantially higher than by sampling of fabrics with the contact plate method or swabbing. It can be concluded that a nondestructive method using a modified Morapex® device can be applied for quick determination of the hygienic condition of textiles.

Comparison of Two Sampling Techniques for the Detection of Malassezia pachydermatis on the Skin of Dogs with Chronic Dermatitis

Adhesive tape strip and dry swab sampling techniques were compared for the detection of Malassezia pachydermatis on the skin of dogs with chronic dermatitis. One hundred and four dogs were sampled by each of the techniques. Two methods, a culture method and a stain method, were used to assess the sampling techniques. By the adhesive tape strip sampling technique, M. pachydermatis was detected on 83 (80%) dogs using the culture method and on 45 (43%) dogs using the stain method. By the dry swab sampling technique, M. pachydermatis was detected on 55 (53%) dogs using the culture method and on 33 (32%) dogs using the stain method. The study showed that the adhesive tape strip sampling technique, using the culture method, detected Malassezia on the skin of significantly more dogs ( P<0.001) than the same technique using the stain method and also significantly more than the dry swab sampling technique, using either the culture or stain methods. It was also shown that an adhesive tape sample could be used to transfer cells to a slide for staining and microscopy prior to being used for culturing Malassezia.

Presence of Yersinia enterocolitica Serotype O:5,27 in Slaughter Pigs

The tonsils, tongue, mesenteric lymph nodes, cecal contents, and feces from 50 slaughter pigs were evaluated for the presence of pathogenic Yersinia enterocolitica. The cecal contents and feces of two pigs were positive (4%) with the pathogenic serotype O:5,27, biotype 3, whereas all other pigs were negative for pathogenic serotypes of Y. enterocolitica. The pathogenic serotypes were isolated from the cecal contents and feces using the stomacher sampling method. The cold enrichment in phosphate buffered saline and plating in Cefsulodin-irgasan-novobiocin medium. No pathogenic serotypes were recovered using the swab sampling technique, enrichment in Irgasan-ticarcillin-chlorate, and plating in modified Salmonella-Shigella deoxycholate-calcium chloride medium. The isolation of only 4% positive pathogenic Y. enterocolitica in our sampling of pigs in one production unit provides some encouragement that detection and control procedures might be effectively implemented to reduce or eliminate serotype O:5,27 from that herd.

SALMONELLA CONTAMINATION OF EQUIPMENT AND BEEF CARCASSES IN THE BERLIN (WEST) SLAUGHTERHOUSE EVALUATED BY VARIOUS ENRICHMENT PROCEDURES

ABSTRACTThe spread of salmonellae in the abattoir environment during the slaughtering of cattle in the Berlin (West) slaughterhouse was investigated. A total of 99 (3. 66%) out of 2704 swab samples were positive. Cutting off the hooves and preskinning gave the highest recovery of salmonellae. Less recoveries were obtained after opening the abdominal cavity. Removal of head, loosening the skin of head, removing the hide and splitting the breastbone and the carcass did not result in the isolation of the organism. Salmonella anatum was the most common isolate. The same serotypes were isolated from both carcasses and equipment. A comparison between Tetrathionate‐enrichment (TTE) and Cystine‐Seleniteenrichment (CSE) was made with 2 different pre‐enrichment periods (6h and 24 h); this was done with swab samples from red meat carcasses and slaughterhouse equipment. Overall, TTE had a higher isolation rate at 24 h preenrichment. The variation between enrichment media may be partly attributable to the multiple swab sampling technique used in the study.