Miniaturization Of Instruments Research Articles

A mini-photofragment translational spectrometer with ion velocity map imaging using low voltage acceleration.

A mini time-sliced ion velocity map imaging photofragment translational spectrometer using low voltage acceleration has been constructed. The innovation of this apparatus adopts a relative low voltage (30-150 V) to substitute the traditional high voltage (650-4000 V) to accelerate and focus the fragment ions. The overall length of the flight path is merely 12 cm. There are many advantages for this instrument, such as compact structure, less interference, and easy to operate and control. Low voltage acceleration gives a longer turn-around time to the photofragment ions forming a thicker Newton sphere, which provides sufficient time for slicing. Ion trajectory simulation has been performed for determining the structure dimensions and the operating voltages. The photodissociation and multiphoton ionization of O2 at 224.999 nm is used to calibrate the ion images and examine the overall performance of the new spectrometer. The velocity resolution (Δν/ν) of this spectrometer from O2 photodissociation is about 0.8%, which is better than most previous results using high acceleration voltage. For the case of CF3I dissociation at 277.38 nm, many CF3 vibrational states have been resolved, and the anisotropy parameter has been measured. The application of low voltage acceleration has shown its advantages on the ion velocity map imaging (VMI) apparatus. The miniaturization of the VMI instruments can be realized on the premise of high resolution.

Design and Fabrication of Laser-Machined Hinge Joints on Miniature Tubes for Steerable Medical Devices

With the proliferation of successful minimally invasive surgical techniques, comes the challenge of shrinking the size of surgical instruments further to facilitate use in applications such as neurosurgery, pediatric surgery, and needle procedures. This paper introduces laser machined, multi-degree-of-freedom (DOF) hinge joints embedded on tubes, as a possible means to realize such miniature instruments without the need for any assembly. A method to design such a joint for an estimated range of motion was explored. The effects of design and machining parameters on the mechanical interference, range of motion, and joint dislocation were analyzed. The extent of interference between the moving parts of the joint can be used to predict the range of motion of the joint for rigid tubes and future design optimization. The total usable workspace was also estimated using kinematic principles for a joint in series and for two sets of orthogonal joints. Our work can open up avenues to a new class of miniature robotic medical devices with hinge joints and a usable channel for drug delivery.

Retrograde intrarenal surgery using ureteral access sheaths is a safe and effective treatment for renal stones in children weighing

Surgical treatment of pediatric kidney stones has changed dramatically in recent years because of the miniaturization of surgical instruments and the availability of intracorporeal lithotripters. The retrograde intrarenal surgery (RIRS) technique is nowadays considered an effective and safe procedure but studies in very young children are lacking and use of a ureteral access sheath (UAS) has also been debated. To assess safety and efficacy of RIRS using UAS in children weighing <20kg. Data from 13 children weighing <20kg who underwent RIRS for renal stones were collected. A Double-J stent was positioned 14 days before surgery. Demographics, stone location, stone number and composition, stone-free status (SFS) and complications were evaluated. Descriptive statistics were applied to describe the cohort. Thirteen patients, age 3.91±1.8 years (mean±SD), underwent 16 RIRS. Mean patient weight and stone burden were 14.88±3.81kg (range 10-20kg) and 15.5±3.8mm (median 16mm), respectively. A UAS was used in 15 out of 16 (93.8%) procedures. SFS was achieved in 81.3% of cases after the first procedure and 100% after auxiliary procedures. Postoperative urinary tract infections with fever (Clavien II) were observed in two (12.5%) patients. Hydrocalyx (Clavien IIIb) was noted in one (6.3%) patient. Patients with stones located in the lower polar calices (p=0.024) and with mixed composition (p=0.036) had a greater prevalence of complications than those with calculi of other compositions located in other sites. After a mean follow-up of 22.4 months no cases of ureteral strictures or vesicoureteral reflux were observed (Table). The current findings support previous evidence showing safety and efficacy of RIRS with use of the UAS in pre-stented very young children. In our experience RIRS seems to be an effective and safe option with a stone-free rate of 81.3% and only 1 severe complication (Clavien-Dindo grade IIIb) and no long-term complications. This study is, to date, the first to examine the safety and efficacy of RIRS using UAS for the treatment of intrarenal stones in a selected cohort of pre-school patients weighing <20kg. RIRS using UAS is an effective and safe procedure for treating kidney stones in pre-school patients weighing <20kg without complications at both short and long term follow up. Stones of mixed composition located in the lower polar calices are associated with a greater risk of postoperative complications.

496 - Percutaneous Assisted-Total Laparoscopic Hysterectomy Using Novel Trocar Configuration: 5-5-2

Advances in technology have been created worthwile interest to further the miniaturization of scar and instruments in minimally invasive surgery. As a consequence, collaboration of surgeons and industry have been focused on to reducing the number of the access ports, decreasing the dimension of trocars from 5- to -3 mm, improving the smaller caliber instruments, and obtaining high resolution optical clarity. Our case is 52 y-old woman was admitted to outpatient clinic with heavy uterine bleeding. Transvaginal ultrasound revealed a 12-week size uterus with multipl fibrodis. After that endometrial biopsy was performed and it showed benign histologic architecture. Hormonal IUD was suggested, but she has opted for surgery instead. Total laparoscopic hysterectomy (TLH) was performed without any complication. She was discharged on postoperative 2nd day. The purpose of this video was to demonstrate the efficacy and feasibility of mini-laparoscopy in combination with percutaneous instrument during TLH.

Percutaneous endoscopic treatment for urinary stones in pediatric patients: where we are now.

Percutaneous nephrolithotomy (PCNL) has been adopted for pyelo-calyceal stones treatment in pediatric patients, starting from the 90's. Very recently, miniaturization of endoscopic instruments allowed less invasive procedures with low complication rate. We reviewed our experience on upper tract stone treatment utilizing two different percutaneous accesses, focusing on the recent new miniaturized devices offered for pediatric renal stones. Patients presenting upper tract urinary stones observed from January 2011 to December 2015 and treated by percutaneous renal access were prospectively evaluated: age, sex, metabolic issues, associated abnormalities, treatment modalities, hospital stay and complication rate were recorded in a specific database. Two different endourological percutaneous modalities were adopted, depending to the stone size and position. PCNL was performed through a direct calyceal puncture under ultrasonographic and fluoroscopic guidance and Amplatz access dilatation till 24 Fr. Ballistic energy was used for fragmentation. Micropercutaneous (Microperc) procedure was recently offered utilizing a 4.85 Fr metallic needle and Holmium:YAG laser lithotripsy under direct vision through a 0.9 mm high resolution optic flexible wire connected with a telescope. Thirty-eight percutaneous access to pyelo-calyceal renal stones were performed on a total of 108 children treated for upper tract stones, aged 4 to 18 years (mean age 7.5 years). The overall number of procedures was 144 (36 repeated procedures). Cystinuria was diagnosed in 5 patients. PCNL was adopted in 28 patients, Microperc was utilized in 8 patients. Hemoglobin dropdown was limited to 1.20±0.80 mg% in PCNL and was not significant in Microperc. No blood transfusion was needed. No significant complications were observed. Stone free rate or minimal not significant residuals were achieved in 82% of PCNL and in 87.5% of Microperc, after a single procedure. Percutaneous endoscopic treatment of renal calculi is feasible in pediatric age, with high success rate in a single step. Advanced miniaturized endoscopic devices as Microperc guarantee high efficacy and reduced complication rate, but endo-urological experience and adequate learning curve are required, especially in small body weight children. Centralization of these patients in Pediatric Stone Centers is welcomed to optimize results and reduce risks.

Performance enhancement of high-field asymmetric waveform ion mobility spectrometry by applying differential-RF-driven operation mode.

The traditional operation mode of high-field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) uses a one-way radio frequency (RF) voltage input as the dispersion voltage. This requires a high voltage input and limits power consumption reduction and miniaturization of instruments. With higher dispersion voltages or larger compensation voltages, there also exist problems such as low signal intensity or the fact that the dispersion voltage is no longer much larger than the compensation voltage. In this paper, a differential-RF-driven operation mode of FAIMS is proposed. The two-way RF is used to generate the dispersion field, and a phase difference is added between the two RFs to generate a single step waveform field. Theoretical analysis, and experimental results from an ethanol sample, showed that the peak positions of the ion spectra changed linearly (R2 = 0.9992) with the phase difference of the two RFs in the differential-RF-driven mode and that the peak intensity of the ion spectrum could be enhanced by more than eight times for ethanol ions. In this way, it is possible to convert the ion spectrum peaks outside the separation or compensation voltage range into a detectable range, by changing the phase difference. To produce the same separation electric field, the high-voltage direct current input voltage can be maximally reduced to half of that in the traditional operation mode. Without changing the drift region size or drift condition, the differential-RF-driven operation mode can reduce power consumption, increase signal-to-noise ratio, extend the application range of the dispersion voltage and compensation voltage, and improve FAIMS detection performance.

Top-down and bottom-up aerosol–cloud closure: towards understanding sources of uncertainty in deriving cloud shortwave radiative flux

Abstract. Top-down and bottom-up aerosol–cloud shortwave radiative flux closures were conducted at the Mace Head Atmospheric Research Station in Galway, Ireland, in August 2015. This study is part of the BACCHUS (Impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) European collaborative project, with the goal of understanding key processes affecting aerosol–cloud shortwave radiative flux closures to improve future climate predictions and develop sustainable policies for Europe. Instrument platforms include ground-based unmanned aerial vehicles (UAVs)1 and satellite measurements of aerosols, clouds and meteorological variables. The ground-based and airborne measurements of aerosol size distributions and cloud condensation nuclei (CCN) concentration were used to initiate a 1-D microphysical aerosol–cloud parcel model (ACPM). UAVs were equipped for a specific science mission, with an optical particle counter for aerosol distribution profiles, a cloud sensor to measure cloud extinction or a five-hole probe for 3-D wind vectors. UAV cloud measurements are rare and have only become possible in recent years through the miniaturization of instrumentation. These are the first UAV measurements at Mace Head. ACPM simulations are compared to in situ cloud extinction measurements from UAVs to quantify closure in terms of cloud shortwave radiative flux. Two out of seven cases exhibit sub-adiabatic vertical temperature profiles within the cloud, which suggests that entrainment processes affect cloud microphysical properties and lead to an overestimate of simulated cloud shortwave radiative flux. Including an entrainment parameterization and explicitly calculating the entrainment fraction in the ACPM simulations both improved cloud-top radiative closure. Entrainment reduced the difference between simulated and observation-derived cloud-top shortwave radiative flux (δRF) by between 25 and 60 W m−2. After accounting for entrainment, satellite-derived cloud droplet number concentrations (CDNCs) were within 30 % of simulated CDNC. In cases with a well-mixed boundary layer, δRF is no greater than 20 W m−2 after accounting for cloud-top entrainment and up to 50 W m−2 when entrainment is not taken into account. In cases with a decoupled boundary layer, cloud microphysical properties are inconsistent with ground-based aerosol measurements, as expected, and δRF is as high as 88 W m−2, even high (&gt; 30 W m−2) after accounting for cloud-top entrainment. This work demonstrates the need to take in situ measurements of aerosol properties for cases where the boundary layer is decoupled as well as consider cloud-top entrainment to accurately model stratocumulus cloud radiative flux. 1The regulatory term for UAV is remotely piloted aircraft (RPA).

Research progress of rapid detection of ochratoxin A and its application prospect in traditional Chinese medicine

Ochratoxin A (OTA) is a toxic secondary metabolite mainly produced by Aspergillus and Penicillium species, with strong renal toxicity, teratogenic, carcinogenic, mutagenic effect. Studies have shown that OTA is not only widely contaminated in food and feed crops, but also has been widely contaminated in Chinese herbal medicines such as spices, licorice and so on. In view of OTA's universality and harmfulness, this paper summarizes the flow visualization test strip, microsphere, electrochemical sensor, surface enhanced Raman spectroscopy technology in OTA rapid detection, which provides reference for the research and application of high throughout detection instrument miniaturization in order to achieve OTA quick detection and simple operation.

State-of-the-art mass spectrometry for point-of-care and other applications: A hands-on intensive short course for undergraduate students

Current mass spectrometry techniques and applications, especially those which achieve high speed by using ambient ionization and/or miniature instruments are presented with emphasis on the nature of the instrumentation and methodology. This is done in the context of describing an intensive two-day workshop for upper division undergraduate students (9th annual meeting for the Center for Analytical Instrumentation Development, CAID, Purdue University). Six hands-on demonstrations are detailed. Multiple ionization sources, types of mass spectrometers, and ion manipulation techniques are covered. The meeting “State-of-the-Art Mass Spectrometry for Point-of-Care and other Applications” might serve as a model for intensive short courses that other institutions might wish to develop in their particular research specialties. A hallmark is the emphasis on methodology, fundamental theory, and current applications. The effectiveness of the CAID short course to deeply immerse, motivate, and educate students was confirmed through formal student assessment and feedback.

Telemedicine and Tele-echocardiography in India

India is a vast nation with almost 75% of their population living in rural and remote regions. The obvious challenge is in the health-care delivery mechanism because of the disparity in the availability of services and specialists across the region. Therefore, the technology that facilitates the delivery of this essential health care to these remote areas is the need of the hour today. Telemedicine which essentially encompasses exchange of clinical information through a communication media has provided a platform for the delivery of quality health care. Advances in Information and Communication Technology in the area of video-to-video communication have led to the growth of extending the reach of specialist services for diagnostic investigations to areas wherein specialists are unavailable. For a country of over one billion, the number of cardiologists available for even screening patients is abysmally low. Echocardiography is often used to diagnose and exclude important cardiac diagnoses in adults and children. The use of telemedicine in echocardiography is one way to alleviate this problem, wherein a diagnosis can be made through the transmitted images and an appropriate management plan suggested based on the findings before there is patient movement. With the right diagnosis, some of them do not need medical intervention in terms of a procedure or surgery, and they can just be managed by medicines. The convergence of science and technology in our dynamic digital era has resulted in the development of innovative digital health devices that allow easy and accurate characterization in health and disease. Internet of Things (IoT)-assisted medical devices have found immense potential in addressing some of the long-standing issues related to diagnostic tests such as electrocardiogram and echocardiography. These technological advancements and the miniaturization of diagnostic instruments have led to decreasing health-care costs and improving outcomes.

Fiber-optic ultrasonic sensors and applications

Fiber-optic ultrasonic sensors possess the ability to detect ultrasonic waves by recovery of light intensity, wavelength, phase, and polarization. Compared with traditional electrical ultrasonic transducers, fiber-optic ultrasonic sensors have several merits, such as broadband response, high sensitivity, disturbance resistance, and good reusability, which are helpful to improve the reliability and efficiency of ultrasonic detection in underwater defense security, bioimaging, nondestructive inspection, and imaging of seismic physical models. To date, according to the principle, fiber-optic ultrasonic sensors can be classified into three types, including intensity modulation, fiber-optic interferometers and fiber gratings. For the intensity-modulated fiber-optic ultrasonic sensors, ultrasonic waves can be detected by measuring optical fiber coupling loss, fiber transmission-reflection loss, fiber reflection loss and fiber polarization loss. The phase difference in fiber-optic interferometers can be modulated by ultrasonic strain. According to the interference mechanism, fiber-optic interferometric ultrasonic sensors are generally based on Mach-Zehnder interference, Fabry-Perot interference, Michelson interference and Sagnac interference. For the ultrasonic sensors based on fiber gratings, the grating length is supposed to be shorter than the ultrasonic wavelength so that the ultrasonic stress presents constant along the fiber gratings. Currently, the approaches of spectral edge filtering and wavelength-matched filtering are utilized to transform optical signals into voltage signals, which highly depend on the slope of the grating spectra. Thus, the fiber gratings with extremely narrow 3-dB bandwidth, such as phase shifted fiber Bragg grating, are preferred for highly sensitive ultrasonic detection. Besides the fiber-optic passive sensing, the distributed feedback fiber laser and distributed Bragg reflector also exhibit outstanding advantages in ultrasonic detection. Fiber-optic ultrasonic detecting technique is one of the hot topics in international research community, which is an effective method to evaluate the microstructure and related mechanical properties, and detect the microcosmic and macroscopic discontinuities of solid materials. In this paper, three typical applications of ultrasonic detection, i.e., monitoring of smart structure and health, biomedical imaging, and imaging of seismic physical models are reviewed, respectively. Our group has been engaged in the research fields of fiber-optic geophones and ultrasonic sensors for seismic exploration for decades. Several fiber-optic ultrasonic sensors with smart packaging are proposed and also used for the scanning imaging of two physical models. In this paper we review the sensing mechanism, fabrication method, and current status of three types of fiber-optic ultrasonic sensors, respectively. Besides, the corresponding applications and technology challenges are also summarized. In particular, we present several kinds of home-made optical fiber ultrasonic sensors as a new technology applied in the imaging of seismic physical models. Overall, after decades of efforts, gratifying achievements have been achieved in the research of fiber-optic ultrasonic sensors. Further work needs to solve various technical issues, such as sensitivity, stability, structural microminiaturization, and multiplexing, etc. The next step will focus on the research issues in ultrasonic detection of seismic physical models, performance improvement, and multiplexing technology for distributed sensing. Miniaturization of fiber sensors and instrumentation of sensing system will also be the important research topic. The final objective of the research is to build a well integrated fiber-optic ultrasonic detecting system with high sensitivity and stability, networking construction, and proprietary intellectual property rights.

Spectral Correction Method of Multi-Channels Near-Infrared Spectrometer and Applications

Near-infrared (NIR) spectrometer based on semiconductor lasers can combine light source and splitter into one, which is an important direction for development of miniature instruments. In order to avoid random interference caused by inconsistency between light sources, the novel evaluation indicators for global stability of multi-channels spectral system were proposed based on the correlation between dynamic deviation spectra of any two channels. The NIR analysis of moisture for corn powder samples based on the partial least squares combined with Savitzky-Golay (SG) smoothing was taken as an example, and a spectral correction method for enhancing prediction performance of multi-channels spectral system was further provided using above evaluation indicators. The experiment results showed that the global stability evaluation indicators significantly increased after SG smoothing correction. Meanwhile, the root-mean-square errors of prediction for corn moisture reduced from 0.373 to 0.283 (%), and the correlation coefficient between predicted and actual values was improved from 0.702 to 0.855. The above results indicated that by improving global stability indicators, the prediction ability of multi-channels spectral system can be improved. The proposed method provided a valuable reference for designing multi-channels diminutive spectrometer with high prediction performance, which had significance for large-scale application of NIR technology.

Extending the mass range of a miniature ion trap mass spectrometer using the inverse Mathieu q scan

The mass/charge range of a mass spectrometer operated in either the boundary or resonance ejection mode is usually limited by the highest radiofrequency (rf) voltage that can be attained, although lowering the resonance ejection Mathieu q value (qeject) can increase this range at the expense of resolution and unintended boundary ejection can result in spectral complexity. High voltage requirements are particularly troublesome for miniature instruments, which have tight electronic constraints and closely-spaced electrodes prone to discharging. Here we demonstrate an alternative approach to mass range extension based on a method of scanning the resonance ejection frequency nonlinearly in the form of an inverse Mathieu q scan. The results show an increase in mass range of up to 3.5 times on both a benchtop LTQ linear ion trap and the Mini 12 miniature linear ion trap mass spectrometer without instrumental modifications, and unit resolution is observed on the benchtop instrument by controlling the scan rate and minimizing space charge effects.

Impact of miniport laparoscopic cholecystectomy versus standard port laparoscopic cholecystectomy on recovery of physical activity: a randomized trial.

We conducted a randomized trial comparing minilaparoscopic cholecystectomy (MLC) to conventional laparoscopic cholecystectomy (CLC) to determine whether MLC accelerated recovery of physical activity after elective surgery (NCT01397565). A total of 115 patients scheduled for elective cholecystectomy were randomized to either CLC or MLC. Both procedures used a 10-mm umbilical port, but the three upper abdominal ports were 5mm in CLC and 3mm in MLC. Primary outcome was self-reported physical activity 1month after surgery as estimated by Community Health Activities Model Program for Seniors questionnaire (kcal/kg/week). Secondary outcomes were umbilical pain, abdominal pain, nausea and fatigue (VAS, 1-10), and cosmetic result at one and 3months. Patients received identical surgical dressings for 1week, and assessors were blinded to group allocation. Forty-two patients randomized to CLC group and 33 patients randomized to MLC remained in the trial and were analyzed. Both groups were similar at baseline characteristics. In the MLC group, at least one 5-mm port was used in 17 (51.5%) mainly due to unavailability of ML equipment. Median (IQR) physical activity for the CLC and MLC groups was similar at baseline (23.4 [13.1, 44.6] vs 23.6 [14.2, 66.9] kcal/kg/week, p=0.35) and at 1month (20 [7.9, 52.5] vs 16.8 [11.8, 28.6] kcal/kg/week, p=0.90). One month post-op, umbilical pain and abdominal pain were similar, but the CLC group reported higher fatigue (4 [1-5] vs 1 [0-4], p=0.05) and worse scar appearance scores (4 [3, 4] vs 4.5 [4, 5], p=0.009). At 3months, the CLC group had worse scar appearance (4 [3-5] vs 5 [4-5], p=0.02) and lower scar satisfaction scores (4 [3, 4] vs 4 [3.5-4], p=0.04). Recovery of physical activity was similar after MLC and CLC. MLC resulted in less fatigue and better scar appearance and satisfaction. These benefits were seen despite the need to upsize one or more ports in more than half of patients related to availability of the miniature instruments.

Chemometric aided NIR portable instrument for rapid assessment of medicine quality

The progress in instrumentation technology has led to miniaturization of NIR instruments. Fast systems that contain no moving parts were developed to be used in the field, warehouses, drugstores, etc. At the same time, in general these portable/handheld spectrometers have a lower spectral resolution and a narrower spectral region than stationary ones. Vendors of portable instruments supply their equipment with special software for spectra processing, which aims at simplifying the analyst’s work to the highest degree possible. Often such software is not fully capable of solving complex problems. In application to a real-world problem of counterfeit drug detection we demonstrate that even impaired spectral data do carry information sufficient for drug authentication. The chemometrics aided approach helps to extract this information and thus to extend the applicability of miniaturized NIR instruments. MicroPhazir-RX NIR spectrometer is used as an example of a portable instrument. The data driven soft independent modeling of class analogy (DD-SIMCA) method is employed for data processing. A representative set of tablets of a calcium channel blocker from 6 different manufacturers is used to illustrate the proposed approach. It is shown that the DD-SIMCA approach yields a better result than the basic method provided by the instrument vendor.

High voltage insulation properties of DLC-Parylene multilayer films for microsurgery instruments

In minimally invasive surgery, there is a continuous trend towards the miniaturization of instruments in order to keep the incisions as small as possible. In this context, extensive use is made of electrosurgery. In order to optimize and miniaturize electrosurgical instruments, new ultrathin insulation methods with film thicknesses below 50μm need to be developed. These electrical insulation films must comply with the requirements of Standard DIN EN ISO 60601-2-2.For this purpose, a high-voltage insulation layer based on a diamond like carbon (DLC) multilayer in combination with a topping layer of Parylene C has been developed. With a total thickness of less than 50μm, this film withstands an electrical high-voltage treatment of more than 1kV required in Standard DIN EN ISO 60601-2-2. In addition to the film's dielectric strength, its adhesion and suitability for reprocessing were investigated.

Novel Technologies in Urologic Surgery: a Rapidly Changing Scenario.

The introduction of laparoscopy and robotic surgery revolutionized the surgical management of urologic patients. Nonetheless, we live in an era of rapid changes, and we are probably still in the infancy of technology applied to surgery. When considering currently available technologies, there are several unmet needs to be addressed. These include the application of augmented reality, haptic feedback, tissue recognition, distant remote control, miniaturization of surgical instruments, the learning curve typical of the introduction of novel techniques, and excessive costs. In the next few years, evolution in imaging modalities in pre- and intraoperative surgical planning, as well as the introduction of novel minimally invasive platforms, would in part address these issues, substantially improving surgical outcomes. In addition, validated training programs would allow for the safe implementation of novel techniques in the clinical practice. Finally, a reduction in costs would be necessary to make technology affordable and to optimize healthcare resources.

Mobile technology and the digitization of healthcare.

The convergence of science and technology in our dynamic digital era has resulted in the development of innovative digital health devices that allow easy and accurate characterization in health and disease. Technological advancements and the miniaturization of diagnostic instruments to modern smartphone-connected and mobile health (mHealth) devices such as the iECG, handheld ultrasound, and lab-on-a-chip technologies have led to increasing enthusiasm for patient care with promises to decrease healthcare costs and to improve outcomes. This 'hype' for mHealth has recently intersected with the 'real world' and is providing important insights into how patients and practitioners are utilizing digital health technologies. It is also raising important questions regarding the evidence supporting widespread device use. In this state-of-the-art review, we assess the current literature of mHealth and aim to provide a framework for the advances in mHealth by understanding the various device, patient, and clinical factors as they relate to digital health from device designs and patient engagement, to clinical workflow and device regulation. We also outline new strategies for generation and analysis of mHealth data at the individual and population-based levels.

Green Analytical Methods in Analysis of Aflatoxins

The detection and determination of aflatoxins at nanogram level is important from human health point of view. Aflatoxins exhibit acute toxicity demonstrating teratogenic, mutagenic and carcinogenic effects. Amongst the available aflatoxins, B1, B2, G1, G2, M1 and M2 have been the more frequently analysed aflatoxins by chromatographic, spectroscopic and immuochemical methods. Because of the presence of aflatoxins at trace level in food and feedstuff used for human and animal consumption, new analytical methods have been designed for sensitive and selective detection and quantification of aflatoxins. Each of the employed analytical methods, described herein, such as thin layer chromatography, high performance liquid chromatography, gas chromatography and immunochemical methods, among others, has inherent merits and demerits in aflatoxins analysis. This chapter critically examines each of the analytical methods currently in use in the analysis of aflatoxins. Deviating from the earlier approaches, this chapter focuses on the need of methodologies that have negligible environmental impact. Though most of the existing methods are highly sensitive and reasonably safer to use but still there is the need of development of new green methodologies focusing on the reduction of solvent consumption, replacement of environmentally hazardous solvents with more benign alternatives, miniaturization of instrumentation and solvent-free sample preparation.

Miniaturized ultra-high performance liquid chromatography coupled to electrochemical detection: Investigation of system performance for neurochemical analysis

The interest in implementation of miniaturized ultra-high performance liquid chromatography (UHPLC) in neurochemical research is growing because of the need for faster, more selective and more sensitive neurotransmitter analyses. The instrument performance of a tailor designed microbore UHPLC system coupled to electrochemical detection (ECD) is investigated, focusing on the quantitative monoamine determination in in vivo microdialysis samples. The use of a microbore column (1.0mm I.D.) requires miniaturization of the entire instrument, though a balance between extra-column band broadening and injection volume must be considered. This is accomplished through the user defined Performance Optimizing Injection Sequence, whereby 5μL sample is injected on the column with a measured extra-column variance of 4.5–9.0μL2 and only 7μL sample uptake. Different sub-2μm and superficially porous particle stationary phases are compared by means of the kinetic plot approach. Peak efficiencies of about 16000–35000 theoretical plates are obtained for the Acquity UPLC BEH C18 column within 13min analysis time. Furthermore, the coupling to ECD is shown suitable for microbore UHPLC analysis thanks to the miniaturized flow cell design, sufficiently fast data acquisition and mathematical data filtering. Ultimately, injection of in vivo samples demonstrates the applicability of the system for microdialysis analysis.