Methodology for rapid assessment of blood lithium levels in ultramicro volumes of blood plasma for applications in personal monitoring of patients with bipolar mood disorder

Bipolar disorder (BD) is a common mental health condition, characterized by extreme changes in mood, energy, and behavior. BD is often managed through mood-stabilizing medications, of which lithium formulations remain the most reliable and effective at reducing the risk of suicide. To achieve adequate and consistent efficacy, lithium concentrations need to be maintained within a narrow therapeutic range (0.4 to 1.2  mmol  /  L). Because of its narrow therapeutic index, long-term lithium therapy is associated with serious side effects and risks of toxicity. It is believed that the availability of a personal blood lithium analyzer would benefit patients who are on lithium treatment. We detail the results of a spectrophotometric method performed on ultramicro volumes to determine blood plasma lithium concentrations as compared with reference measurements of flame photometry, and validated in samples of unknown lithium content. Applying multiple linear regression, lithium concentrations could be determined in a rapid manner using full-range spectra or triwavelength data. Both techniques highly correlated with reference standards and could predict lithium levels accurately (R2  =  0.794214 and RMSEP  =  0.209584, and R2  =  0.863921 and RMSEP  =  0.167524, respectively). Therefore, this method can be a useful for rapid assessment of blood lithium in nonlaboratory settings i.e., general practices, hospital clinics, and community health centers by healthcare professionals and/or by patients. Future work will now focus on completion of a miniaturized and integrated system that will deliver a portable and personal lithium-monitoring device

Optical analysis of Lithium Carbonate: Towards the development of a Portable Lithium Blood Level analyzer for Bipolar Disorder Patients

Lithium medication is the gold standard of treatment in Bipolar Disorder patients, preventing and reducing mood swings and suicidality. However, despite its effectiveness, it is a potentially hazardous drug requiring regular monitoring of blood levels to ensure toxic levels are not reached. This paper describes the first steps towards developing a new portable device that can be used by Bipolar Disorder patients to facilitate the analysis of lithium blood levels at home. Solutions of lithium carbonate have been optically fingerprinted using a high-end spectrophotometer. Preliminary measurements indicate that while the visible to near infrared region of the absorption spectra fall heavily within the water band, measurements in the Ultraviolet region show a strong distinction between different lithium concentrations. The optical spectra of Lithium in the 220 nm to 230 nm region demonstrated the ability to differentiate between concentrations representing those found in patients

A Method for Rapid, Reliable, and Low-Volume Measurement of Lithium in Blood for Use in Bipolar Disorder Treatment Management

GOAL: Lithium preparations are considered the most reliable mood stabilizers for patients with Bipolar Disorder (BD), and are the most effective at reducing the risk of suicide. However, maintaining blood lithium concentration within the narrow therapeutic range of 0.4-1.2 mEq is crucial but extremely difficult. The aim of this work is to develop a personal lithium blood level analyzer using a novel method of combined optical and electrical impedance spectroscopy to test micro volumes of spiked samples of human blood. RESULTS: Impedance measurements alone showed a limit of detection of less than 0.1 mEq within the therapeutic range, whereas optical measurements could verify the presence of lithium and provide a degree of lithium content. Optical specificity to lithium was further verified in qualitative assessment of lithium spiked blood samples with varying concentrations of sodium. Moreover, analysis of multiple linear regression yielded a prediction model of R2 = 0.322716 and RMSEP =0.223602 for optical measurements only using feature wavelengths, which were found to appear at minima 560 and 605 nm. Combined with impedance measurements, prediction of lithium concentration in samples with unknown lithium content was significantly increased to R2 = 0.876438, and RMSEP = 0.513554. CONCLUSION: The combination of optical and impedance modalities for determinations of blood lithium resulted in significant improvement to the sensitivity and accuracy of measurement. SIGNIFICANCE: Results are complementary of the proposed opto-impedance method, and future work will now focus on the technical development of an integrated and miniaturized system for measurement of lithium levels in blood with a high level of accuracy and sensitivity

The Embodied and Situated Nature of Moods

This is the final version of the article. Available from Springer via the DOI in this record.In this paper I argue that it is misleading to regard the brain as the physical basis or “core machinery” of moods. First, empirical evidence shows that brain activity not only influences, but is in turn influenced by, physical activity taking place in other parts of the organism (such as the endocrine and immune systems). It is therefore not clear why the core machinery of moods ought to be restricted to the brain. I propose, instead, that moods should be conceived as embodied, i.e., their physical basis should be enlarged so as to comprise not just brain but also bodily processes. Second, I emphasise that moods are also situated in the world. By this I do not simply mean that moods are influenced by the world, but that they are complexly interrelated with it, in at least three different ways: they are shaped by cultural values and norms; they are materially and intersubjectively “scaffolded”; and they can even “experientially incorporate” parts of the world, i.e., include the experience of parts of the world as part of oneself