This work presents a polymeric centrifugal microfluidic platform for the rapid and sensitive identification of bacteria directly from urine, thus eliminating timeconsuming cultivation steps. This "Lab-on-a-Disc" platform utilizes the rotationally induced centrifugal field to efficiently capture bacteria directly from suspension within a glass-polymer hybrid chip. Once trapped in an array of small V-shaped structures, the bacteria are readily available for spectroscopic characterization, such as Raman spectroscopic fingerprinting, providing valuable information on the characteristics of the captured bacteria. Utilising fluorescence microscopy, quantification of the bacterial load has been achieved for concentrations above 2 Â 10 À7 cells ml À1 within a 4 ll sample. As a pilot application, we characterize urine samples from patients with urinary tract infections. Following minimal sample preparation, Raman spectra of the bacteria are recorded following centrifugal capture in stopped-flow sedimentation mode. Utilizing advanced analysis algorithms, including extended multiplicative scattering correction, high-quality Raman spectra of different pathogens, such as Escherichia coli or Enterococcus faecalis, are obtained from the analyzed patient samples. The whole procedure, including sample preparation, requires about 1 h to obtain a valuable result, marking a significant reduction in diagnosis time when compared to the 24 h and more typically required for standard microbiological methods. As this cost-efficient centrifugal cartridge can be operated using low-complexity, widely automated instrumentation, while providing valuable bacterial identification in urine samples in a greatly reduced time-period, our opto-microfluidic Lab-on-a-Disc device demonstrates great potential for nextgeneration patient diagnostics at the of point-of-care. V C 2015 AIP Publishing LLC.

A disadvantage in Q fever diagnostics and research is the insensitive and difficult culture of Coxiella burnetii. This intracellular organism can only be isolated using embryonated eggs, animal hosts, or mammalian cell culture. In consequence, it has only been possible to isolate a few strains from human patients. Here, we describe the first isolation of C. burnetii from a clinical specimen using the recently developed cell-free medium acidified citrate cysteine medium 2 (ACCM2). We screened the sera of 217 patients who had undergone valvular transplantation but detected one serum with an antibody constellation indicating chronic Q fever. Polymerase chain reaction (PCR) of the corresponding heart valve revealed 3.1 × 10(5) copies/rxn. The strain was successfully isolated using ACCM2. Genomic investigation by multilocus variable-number of tandem repeat (VNTR) analysis (MLVA) revealed the strain to be a new genotype, A10, closely related to one from sheep. As the sensitivity of ACCM2 for different human strains is unknown, we also investigated combining a robust test, egg propagation, with ACCM2. This combination produced four to six logs of growth of the bacteria. The use of ACCM2 in this combination simplified the otherwise elaborate purification steps. Cultivation in ACCM2 has the potential to simplify the isolation of C. burnetii in a clinical setting. As the success rates of cell culture for virulent C. burnetii strains are variable, the sensitivity of ACCM2 for different strains is unknown, and many specimens may contain much fewer bacteria than in our case, the combination of the robust method of egg propagation with ACCM2 is a good alternative to existing single methods for investigating critical specimens.