Light Energy Conversion Surface with Gold Dendritic Nanoforests/Si Chip for Plasmonic Polymerase Chain Reaction.

Surfaces with gold dendritic nanoforests (Au DNFs) on Si chips demonstrate broadband-light absorption. This study is the first to utilize localized surface plasmons of Au DNFs/Si chips for polymerase chain reaction (PCR) applications. A convenient halogen lamp was used as the heating source to illuminate the Au DNFs/Si chip for PCR. A detection target of Salmonella spp. DNA fragments was reproduced in this plasmonic PCR chip system. By semi-quantitation in gel electrophoresis analysis, the plasmonic PCR with 30 cycles and a largely reduced processing time provided results comparable with those of a commercial PCR thermal cycler with 40 cycles in more than 1 h. In the presence of an Au DNFs/Si chip, the plasmonic PCR provides superior results in a short processing time.

Role of the Diphosphine Chelate in Emissive, Charge-Neutral Iridium(III) Complexes.

A class of neutral tris-bidentate IrIII metal complexes incorporating a diphosphine as a chelate is prepared and characterized here for the first time. Treatment of [Ir(dppBz)(tht)Cl3 ] (1, dppBz=1,2-bis(diphenylphosphino)benzene, tht=tetrahydrothiophene) with fppzH (3-trifluoromethyl-5-(2'-pyridyl)-1H-pyrazole) afforded the dichloride complexes, trans-(Cl,Cl)[Ir(dppBz)(fppz)Cl2 ] (2) and cis-(Cl,Cl)[Ir(dppBz)(fppz)Cl2 ] (3). The reaction of 3 with the dianionic chelate precursor, 5,5'-di(trifluoromethyl)-3,3'-bipyrazole (bipzH2 ) or 5,5'-(1-methylethylidene)-bis(3-trifluoromethyl-1H-pyrazole) (mepzH2 ), in DMF gave the tris-bidentate complex [Ir(dppBz)(fppz)(bipz)] (4) or [Ir(dppBz)(fppz)(mepz)] (5), respectively. In contrast, a hydride complex [Ir(dppBz)(fppz)(bipzH)H] (6) was isolated instead of 4 in protic solvent, namely: diethylene glycol monomethyl ether (DGME). All complexes 2-6 are luminescent in powder form and thin films where the dichlorides (2, 3) emit with maxima at 590-627 nm (orange) and quantum yields (QYs) up to 90 % whereas the tris-bidentate (4, 5) and hydride (6) complexes emit at 455-458 nm (blue) with QYs up to 70 %. Hybrid (time-dependent) DFT calculations showed considerable metal-to-ligand charge transfer contribution to the orange-emitting 2 and 3 but substantial ligand-centered 3 π-π* transition character in the blue-emitting 4-6. The dppBz does not participate in the radiative transitions in 4-6, but it provides the rigidity and steric bulk needed to promote the luminescence by suppressing the self-quenching in the solid state. Fabrication of an organic light-emitting diode (OLED) with dopant 5 gave a deep-blue CIE chromaticity of (0.16, 0.15). Superior blue emitters, which are vital in OLED applications, may be found in other neutral IrIII complexes containing phosphine chelates.

Improvement of strain discrimination by combination of superantigen profiles, PFGE, and RAPD for Staphylococcus aureus isolates from clinical samples and food-poisoning cases.

Staphylococcus aureus is one of the major bacterial species that may cause clinical infection and food-poisoning cases. Strains of this bacterial species may produce a series of superantigens (SAgs) (i.e., staphylococcal enterotoxins [SEs], staphylococcal enterotoxin-like toxins, and toxic shock syndrome toxin). In this study, S. aureus strains from clinical samples and food-poisoning cases in Taiwan were collected; their SAg profiles, and SmaI digestion patterns determined by pulsed-field gel electrophoresis (PFGE), were then analyzed. Results showed that their SAg gene profiles and SmaI digestion patterns of chromosomal DNA were highly diverse. Although PFGE has been used as a criterion standard for typing of S. aureus strains, and the SAg profiles have been used in combination with PFGE for typing of S. aureus strains, we found that strains grouped in these combined patterns could be further discriminated by the random amplified polymorphic DNA (RAPD) method. Thus, the combined use of SAg profiles, PFGE, and RAPD patterns permits high discrimination for typing of S. aureus strains from not only the clinical samples but also the food-poisoning cases. Such a combined method may be used as a highly accurate approach for epidemiological study and tracing of the contamination origin of staphylococcal infections either in hospitals or food-poisoning cases.

Development of PCR primers and a DNA macroarray for the simultaneous detection of major Staphylococcus species using groESL gene.

Staphylococcus spp., including S. aureus, S. intermedius, S. hyicus, S. epidermidis, S. saprophyticus, S. haemolyticus, S. xylosus, and S. carnosus, are major bacterial species associated with food poisoning, and human and veterinary clinics. Traditional methods for the identification of these staphylococci are time-consuming, laborious, or inaccurate. Therefore, rapid and accurate diagnostic methods are needed. In this study, we designed the DNA probes and polymerase chain reaction (PCR) primers for the detection of the aforementioned Staphylococcus species. These primers were proved to be specific for the detection of their corresponding target strains. Furthermore, by using a consensus primer pair, we were able to co-amplify the intergenic region of groES-groEL for these staphylococci. Followed by a chromogenic macroarray system with the specific probes on the plastic chips, these staphylococci in milk products or clinical samples could be simultaneously detected. When the system was used for the inspection of milk or urine samples containing N × 10° target cells per milliliter of the sample, all these staphylococcal species could be identified after an 8-h pre-enrichment step. This system also allowed the adequate diagnosis of bacteremia, since N × 10° target cells per milliliter of the blood samples could be detected after a 12-h pre-enrichment. Compared to the multiplex PCR method, this approach has the additional advantage that it allowed the discrimination of more bacterial strains-even some bacterial strains that may generate PCR products with the same molecular sizes.

Development and use of tuf gene-based primers for the multiplex PCR detection of Lactobacillus acidophilus, Lactobacillus casei group, Lactobacillus delbrueckii, and Bifidobacterium longum in commercial dairy products.

PCR primers specific for the detection of Lactobacillus acidophilus, Lactobacillus casei group, Lactobacillus delbrueckii, and Bifidobacterium longum were designed based on the elongation factor Tu gene (tuf). The specificity of these four primer sets were confirmed by PCR with 88 bacterial strains of Lactobacillus, Enterococcus, Bifidobacterium, and other bacterial species. Results indicated that these primer sets generated predicted PCR products of 397, 230, 202, and 161 bp for L. acidophilus, L. delbrueckii, L. casei group, and B. longum, respectively. Bacterial species other than the target organisms tested did not generate false-positive results. When these four primer sets were combined for the simultaneous detection of the lactic acid bacteria (LAB) in fermented milk products including yogurt, the LAB species listed on the labels of these products could be identified without the preenrichment step. The identification limit for each LAB strain with this multiplex PCR method was N X 10(3) CFU/ml in milk samples. The results of our multiplex PCR method were confirmed by PCR assay using primers based on the 16S rDNA or the 16S-23S intergenic spacer region and by biochemical tests using the API 50 CHL kit. When this multiplex PCR method was used with the determination of counts of total viable LAB and bifidobacteria, the quality of commercial fermented milk products could be assured.

Development and use of a chromogenic macroarray system for the detection of Staphylococcus aureus with enterotoxin A, B, C, D, E, and G genes in food and milk samples.

Abstract Staphylococcus aureus is one of the major pathogens that can cause staphylococcal infection and food poisoning. There are five major classical types of staphylococcal enterotoxins (SEs): SEA, SEB, SEC, SED, and SEE, as well as new SEs or SE-like superantigens (SAgs), such as SEG to SEU. Since many S. aureus strains harbor more than one SE gene and identification of SEs involved in food poisoning cases is time consuming, we developed a chromogenic macroarray method that allows convenient and simultaneous detection of classical SE genes and a new SE gene (seg), which is phylogenetically highly related to seb and sec. Two sets of degenerated primers labeled with biotin were used to co-amplify all SE genes in S. aureus strains through the polymerase chain reaction (PCR). Afterwards, these biotin-labeled PCR products were hybridized with SE gene-specific probes spotted on the nitrocellulose membrane. When this macroarray was used to detect enterotoxingenic S. aureus in milk or beef homogenate containing 10(0)-10(4) target cells per milliliter or gram of the sample, all six enterotoxin genes could be identified after a 12-hour enrichment step. This macroarray offers clinical and food inspection laboratories a rapid and economical visual method to detect common enterotoxigenic S. aureus strains.

PCR detection of Staphylococcal enterotoxins (SEs) N, O, P, Q, R, U, and survey of SE types in Staphylococcus aureus isolates from food-poisoning cases in Taiwan.

Staphylococcal enterotoxins (SEs) are superantigenic toxins. They are five major classical types, i.e., SEA, SEB, SEC, SED, SEE, and new SEs or SE-like superantigens, such as SEG to SEU. Only the staphylococcal superantigens (SAgs) that induce emesis following oral administration in a monkey model are designated as SEs while other related toxins are called SE-like (SEl) superantigens. To survey the enterotoxin genotypes for S. aureus strains isolated from food-poisoning cases in Taiwan, we developed PCR primers specific for SEN, SEO, SEP, SEQ, SER, and SEU genes. The complete SE sequences and their expression potential for strains positive to sen, seo, sep, seq, ser, and seu specific primers were also determined. These strains were used as reference strains. With the PCR primers specific for all SEs or SAgs, including toxic shock syndrome toxin I (TSST-1), we assayed the genotypes of 147 S. aureus strains isolated from patients associated with staphylococcal food-poisoning outbreaks occurred during 2001-2003. For these 147 strains, 135 (91.8%) were found positive for one or more SE or SAg genes. For classical enterotoxin and TSST-1 types, the major one was tsst-1 (59.1%) following by sea (29.2%), seb (19.7%), sec (6.8%), and sed (2.0%). For new SE and SAg types, the major one was sei (29.9%) and sep (27.9%) followed by, sek (16.3%), seo (14.3%), seu (14.2%), sem (11.6%), sen (10.9%), seq (10.9%), seh (8.2%), sel (6.8%), and ser (5.4%) etc. This report reveals the whole SE and SAg genotypes for S. aureus strains isolated from staphylococcal food-poisoning cases in Taiwan.

Designing a biochip following multiplex polymerase chain reaction for the detection of Salmonella serovars Typhimurium, Enteritidis, Infantis, Hadar, and Virchow in poultry products.

Salmonella-contaminated foods, especially poultry-derived foods (eggs, chicken meat), are the major source of salmonellosis. Not only in the European Union (EU), but also in the United States, Japan, and other countries, has salmonellosis been an issue of concern for food safety control agencies. In 2005, EU regulation 1003/2005 set a target for the control and reduction of five target Salmonella enterica serovars-S. Typhimurium, S. Enteritidis, S. Infantis, S. Hadar, and S. Virchow-in breeding flocks. Thus, a simple biochip for the rapid detection of any of these five Salmonella serovars in poultry products may be required. The objectives of this study were to design S. Virchow-specific primers and to develop a biochip for the simultaneous identification of all or any of these five Salmonella serovars in poultry and poultry products. Experimentally, we designed novel polymerase chain reaction (PCR) primers for the specific detection of S. Virchow, S. Infantis, and S. Hadar. The specificity of all these primers and two known primer sets for S. Typhimurium and S. Enteritidis was then confirmed under the same PCR conditions using 57 target strains and 112 nontarget Salmonella strains as well as 103 non-Salmonella strains. Following multiplex PCR, strains of any of these five Salmonella serovars could be detected by a chromogenic biochip deployed with DNA probes specific to these five Salmonella serovars. In comparison with the multiplex PCR methods, the biochip assay could improve the detection limit of each of the Salmonella serovars from N×103 cfu/mL to N×102 cfu/mL sample in either the pure culture or the chicken meat samples. With an 8-hour enrichment step, the detection limit could reach up to N×100 cfu/mL.

Real-time PCR detection of Staphylococcus aureus in milk and meat using new primers designed from the heat shock protein gene htrA sequence.

Staphylococcus aureus may cause foodborne disease outbreaks and staphylococcal infections and is one of the major causes of mastitis. Rapid and reliable methods for detection of this microorganism in milk and other foods are needed. In this study, we designed a primer set from the sequence of the heat shock protein gene htrA, a gene coding for high-temperature-requirement A (HtrA) protein, and used it for real-time PCR detection of S. aureus isolates: 16 reference strains and 40 strains isolated from food-poisoning cases. All strains tested generated positive results. Bacterial strains other than S. aureus, including strains of other Staphylococcus species, did not produce positive results. When this primer set was used for the real-time PCR detection of S. aureus in milk and meat samples without the preenrichment step, samples with target cell numbers greater than 10(3) CFU/ml or CFU/g could be detected, indicating the potential quantitative ability of this real-time PCR assay. With a 10-h preenrichment step, however, a detection limit of 1 CFU/ml or CFU/g could be obtained.

Designing primers and evaluation of the efficiency of propidium monoazide - Quantitative polymerase chain reaction for counting the viable cells of Lactobacillus gasseri and Lactobacillus salivarius.

The purpose of this study is to evaluate the efficiency of using propidium monoazide (PMA) real-time quantitative polymerase chain reaction (qPCR) to count the viable cells of Lactobacillus gasseri and Lactobacillus salivarius in probiotic products. Based on the internal transcription spacer and 23S rRNA genes, two primer sets specific for these two Lactobacillus species were designed. For a probiotic product, the total deMan Rogosa Sharpe plate count was 8.65±0.69 log CFU/g, while for qPCR, the cell counts of L. gasseri and L. salivarius were 8.39±0.14 log CFU/g and 8.57±0.24 log CFU/g, respectively. Under the same conditions, for its heat-killed product, qPCR counts for L. gasseri and L. salivarius were 6.70±0.16 log cells/g and 7.67±0.20 log cells/g, while PMA-qPCR counts were 5.33±0.18 log cells/g and 5.05±0.23 log cells/g, respectively. For cell dilutions with a viable cell count of 8.5 log CFU/mL for L. gasseri and L. salivarius, after heat killing, the PMA-qPCR count for both Lactobacillus species was near 5.5 log cells/mL. When the PMA-qPCR counts of these cell dilutions were compared before and after heat killing, although some DNA might be lost during the heat killing, significant qPCR signals from dead cells, i.e., about 4-5 log cells/mL, could not be reduced by PMA treatment. Increasing PMA concentrations from 100 µM to 200 µM or light exposure time from 5 minutes to 15 minutes had no or, if any, only minor effect on the reduction of qPCR signals from their dead cells. Thus, to differentiate viable lactic acid bacterial cells from dead cells using the PMA-qPCR method, the efficiency of PMA to reduce the qPCR signals from dead cells should be notable.

First N-Borylated Emitters Displaying Highly Efficient Thermally Activated Delayed Fluorescence and High-Performance OLEDs.

Despite the fast boom of thermally activated delayed fluorescence (TADF) emitters bearing borane-based acceptor, so far, no TADF emitter with a direct B-N linkage between N-donor and boryl acceptor has been reported. The latter should simplify the molecular architecture and hence facilitate the synthetic design and versatility. We report here the preparation and characterization of a new series of N-borylated compounds with functional acridine donor unit; namely: ACBM, PACBM, and SACBM. Spectroscopic studies were performed to explore their photophysical properties that exhibited prominent solvatochromism and thermally activated delayed fluorescence. The time-dependent DFT calculation indicated the involvement of substantial intramolecular charge transfer character for which HOMO and LUMO are spatially separated. For compound SACBM, fabrication of green emitting OLED gave CIE chromaticity of (0.22, 0.59) and maximum external quantum efficiency, luminance efficiency and power efficiency of 19.1%, 60.9 cd/A, and 43.6 lm/W, respectively, demonstrating for the first time the highly efficient OLEDs using N-borylated TADF emitters.

Identification of Bacillus spp., Escherichia coli, Salmonella spp., Staphylococcus spp. and Vibrio spp. with 16S ribosomal DNA-based oligonucleotide array hybridization.

Rapid identification of the genus and species of bacteria in foods and clinical specimens is important. In this report, DNA sequences of bacterial 16S rDNA were used to develop the oligonucleotide array for the identification of bacterial strains of Bacillus spp., Escherichia coli, Salmonella spp., Staphylococcus spp. and Vibrio spp. Most of these bacterial strains may cause food-borne outbreaks or sporadic cases. A rapid (<4 h) detection method that used universal PCR primers to amplify the variable regions of bacterial 16S rDNA, followed by reverse hybridization of the PCR products, which were biotin labeled, to the oligonucleotides arrayed on the chip was developed. Fifteen oligonucleotide probes were selected and spotted on the nylon strip to determine the array hybridization patterns. It was successful in discriminating Bacillus spp., E. coli, Salmonella spp., Staphylococcus spp. and Vibrio spp. with identification, in general, to the genus level, not species level. As 182 randomly selected strains were assayed, the detection rate was found higher than 98%. Except for 3 strains, the remaining 179 strains were correctly identified and no cross reactions were observed. These 179 strains generated five hybridization patterns. Adding more oligonucleotide probes to the array may allow the detection of more bacterial genera and species without significantly increasing the complexity or cost.

PCR primers for the detection of staphylococcal enterotoxins K, L, and M and survey of staphylococcal enterotoxin types in Staphylococcus aureus isolates from food poisoning cases in Taiwan.

Staphylococcal enterotoxins (SEs) are important causative agents in gastroenteritidis and food poisoning cases. They are serologically grouped into five major classical types, i.e., SEA, SEB, SEC, SED, and SEE. In addition, new SEs, such as SEG through SEM, have recently been identified and characterized. In an attempt to survey the distribution of classical and new SEs in organisms responsible for staphylococcal infections in Taiwan, we developed PCR primers for the genes that define the SEK, SEL, and SEM types. Bacterial strains other than sek, sel, and sem Staphylococcus aureus, including strains of other Staphylococcus species, did not generate any false-positive results when examined with these primers. The expression potential for the sek, sel, and sem types were also determined by reverse transcription-PCR. Together with the PCR primers specific for the classical SEs and other new SEs, including SEG, SEH, SEI, and SEJ, we surveyed the SE genes in S. aureus strains isolated from food poisoning cases. For 147 S. aureus isolates originating from food poisoning cases, 109 (74.1%) were positive for one or more SE genes. Of them, the major classical enterotoxin type was sea (28.6%), followed by seb (20.4%), sec (8.2%), and sed (2.0%). For the new SE types, sei (30.6%) was detected the most often, followed by sek (18.4%), sem (12.9%), and sel (8.2%). Also, 64 (43.5%) of the total bacterial strains had more than one enterotoxin gene.

Rapid screening of roundup ready soybean in food samples by a hand-held PCR device.

Insulated isothermal PCR (iiPCR) method was recently available for rapid on-site detection of roundup ready soybean (RRS; event GTS40-3-2) in food materials and products. Performance of this method was evaluated in this study. The 100% detection endpoint for the RRS by iiPCR was found in samples containing 0.1% RRS, equivalent to the results of the reference real-time PCR (rtPCR). Analysis of nucleic acids of soybean-based processed food products indicated 95% agreement between the iiPCR and rtPCR for RRS detection. By testing soybean milk and tofu samples using simple pretreatment methods, we found that the agreements between iiPCR and rtPCR methods of the aforementioned samples were 80% and 90%, respectively. Replicated tests of all discrepant samples implied that these samples had trace amounts of RRS, suggesting that the iiPCR system is more sensitive than the rtPCR method. In conclusion, the iiPCR technology can be a useful point-of-need tool to help make a timely decision in the consumption of genetically modified organisms.

Strain Discrimination of Staphylococcus aureus Using Superantigen Profiles.

Staphylococcus aureus is one of the major bacterial species that may cause clinical infection and food-poisoning cases. Strains of this species may produce a series of superantigens (SAgs). Due to the importance of staphylococcal infections, reliable methods for the discrimination of strains of this species are important. Such data may allow us to trace the infection origins and be used for epidemiological study. For strain discrimination, genotyping methods, such as pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD), and multi-locus sequence typing (MLST), etc., could be used. Recently, toxin gene profiles, which can be used for the elucidation of the genetic and pathogenic relatedness between strains, also have been used to improve the strain discrimination. For S. aureus, as more SAg genes were discovered, the SAg profiles become more useful for the strain discrimination of S. aureus. In this chapter, a method for the discrimination of S. aureus strains using superantigen profiles will be described in detail.

The sequence heterogenicities among 16S rRNA genes of Salmonella serovars and the effects on the specificity of the primers designed.

Previously, we have reported a 16S rDNA targeted polymerase chain reaction (PCR) method for the specific detection of Salmonella serovars [J. Appl. Bacteriol. 80 (1996) 659]. The target sites of its primers, i.e. 16SFI and 16SIII, according to the data in GenBank, were found mismatched to the corresponding sequences of some Salmonella serovars, such as those of S. Houten, S. Chingola, S. Bareilly, and S. Weltevreden. Accordingly, a PCR method using a nonspecific primer MINf combined with a primer modified from our 16SFI primer, i.e. the primer MINr, was developed and displayed better detection specificity [Int. J. Food Microbiol. 80 (2003) 67]. In this study, we show the sequence heterogenicity at the primer 16SFI targeting sites for some Salmonella serovars. Thus, the sequence used for designing of PCR primers might be just one of the several possible sequences. Such a situation may lead to the misjudgment on evaluation of the specificity of the primers if this was only based on the data in GenBank. Strains of the above described Salmonella serovars with target sequences from GenBank mismatched to the primer 16SF1 were reidentified and their PCR results were confirmed. Meanwhile, their 16SFI/16SIII primer annealing sites were sequenced and the sequences obtained were found completely and highly homologous to those of 16SFI and complementary to those of 16SIII primer, respectively.

Preserving confidentiality when sharing medical database with the Cellsecu system.

We propose a computer system called Cellsecu that maintains the anonymity and the confidentiality of each cell containing sensitive information in medical database. Cellsecu attains this by automatically removing, generalizing, and expanding information. It is designed to enhance data privacy protection so a data warehouse can automatically handle queries. In most cases, health organizations collect medical data with explicit identifiers, such as name, address and phone number. Simply removing all explicit identifiers prior to release of the data is not enough to preserve the data confidentiality. Remaining data can be used to re-identify individuals by linking or matching the data to other database, or by looking at unique characteristics found in the database. A formal model based on Modal logic is the theoretical foundation of Cellsecu. As well, a new confidentiality criteria called "non-uniqueness" is defined and implemented. We believe modeling this problem formally can clarify the issue as well as clearly identify the boundary of current technology. Base on our preliminary performance evaluation, the confidentiality check module and the confidentiality enhancing module only slightly degrade system performance.

Enhancement of the immune response against Salmonella infection of mice by heat-killed multispecies combinations of lactic acid bacteria.

Heat-killed lactic acid bacteria (LAB) has advantages over live LAB in that it has a long shelf-life and is therefore easy to store and transport. From four LAB strains selected by immunomodulatory activity and adherent properties, we prepared the heat-killed multispecies combination of LAB (MLAB) and the cell walls from MLAB under two conditions (100 °C for 30 min and 121 °C for 15 min). Different effects on the adherent properties of these four LAB strains were observed, depending on the heating conditions. With mouse macrophage cells, the two heat-killed MLABs (HMLABs) showed significantly higher induction activities on the production of interleukin 12 (IL-12) than their individual strains did. Heat-killed MLABs and cell-wall preparations were able to reduce the Salmonella invasion of Caco-2 and mouse macrophage cells. Feeding mice with HMLAB could inhibit the Salmonella invasion of mice significantly. For these mice, the expression level of pro-inflammatory cytokines, such as TNF-α and IL-6, in mouse serum was reduced while that of the anti-inflammatory cytokine, i.e. IL-10, was enhanced. The HMLABs developed in this study showed higher protective effect against Salmonella invasion either of Caco-2 cells or of mice, relative to the heat-killed lactobacilli, which consisted of Lactobacillus acidophilus strains selected at random. In conclusion, the HMLABs were potentially useful for the protection of mice against Salmonella infection and the induced inflammation.

Detection of Salmonella in chicken meat by insulated isothermal PCR.

Consumption of Salmonella-contaminated foods, such as poultry and fresh eggs, is known to be one of the main causes of salmonellosis. Conventional PCR methods, including real-time PCR for rapid detection of Salmonella, in general require skilled technicians and costly instruments. A recently developed novel convective PCR, insulated isothermal PCR (iiPCR), is carried out in polycarbonate capillary tubes. In this study, we designed TaqMan probes and PCR primers based on the yrfH gene encoding a heat shock protein for the iiPCR detection of Salmonella in chicken meat samples. The TaqMan probe was labeled with 6-carboxyfluorescein and 6-carboxytetramethylrhodamine at the 5' and 3' ends, respectively. The PCR amplicon was 133 bp. A typical run of this iiPCR assay was completed within 1 h. Specific PCR products were obtained for 148 strains representing 49 serotypes of Salmonella tested. Under the same conditions, false-positive results were not obtained for 98 non-Salmonella strains tested, including strains of Enterobacteriaceae closely related to Salmonella. For chicken meat samples, with a 5-h enrichment step Salmonella at as low as 10° CFU/g of poultry meat could be detected. Because the amplification signals from the probes are detectable at 520 nm, identification of the PCR products by gel electrophoresis is not required. Compared with conventional PCR, the iiPCR system requires less expertise and provides an economical, reliable, and rapid tool for result interpretation. Detection results can be obtained within 8 h, including the enrichment and DNA extraction steps.