An apparatus detects a material within a sample using signal generation circuitry that generates an orbital angular momentum (OAM) twisted light beam having at least one orbital angular momentum applied thereto. The signal generation circuitry applies the at least one OAM twisted light beam to the sample. The OAM twisted light beam includes at least one fractional OAM state, at least one intensity signature and at least one phase signature unique to the material within the sample. A detector receives the OAM twisted light beam after the OAM twisted light beam passes through the sample and detects the material responsive to a presence of a unique combination of the at least one fractional OAM state, the at least one intensity signature and the at least one phase signature.

Provided herein are Mycobacterium smegmatis porin nanopores, systems that comprise these nanopores, and methods of using and making these nanopores. Such nanopores may be wild-type MspA porins, mutant MspA porins, wild-type MspA paralog porins, wild-type MspA homolog porins, mutant MspA paralog porins, mutant MspA homolog porins, or single-chain Msp porins. Also provided are bacterial strains capable of inducible Msp porin expression.

An apparatus that measures a concentration of a material within a sample includes signal generation circuitry that generates a first signal having at least one orthogonal function applied thereto and applies the first signal to the sample. A detector receives the first signal after the first signal passes through the sample and determines the concentration of the material within the sample based on a detected orthogonal function within the first signal received from the sample.

An apparatus that measures a concentration of a material within a sample includes signal generation circuitry that generates a first signal having at least one orthogonal function applied thereto and applies the first signal to the sample. A detector receives the first signal after the first signal passes through the sample and determines the concentration of the material within the sample based on a detected orthogonal function within the first signal received from the sample.

The present disclosure relates to the identification of components in a sample based on the chemical nature of the component. In particular, although not exclusively, the present disclosure relates to the identification of hydrophobic and hydrophilic components using a mass spectrometric technique. The present invention also relates to kits and products used in the identification of the components, as well as other subject matter.

The invention relates to the detection of DHA and EPA. In a particular aspect, the invention relates to methods for detecting DHA and EPA by mass spectrometry and kits for carrying out such methods.

Described herein are mass spectrometry systems and methods which improve the accuracy of isobaric tag-based quantification by alleviating the pervasive problem of precursor interference and co-isolation of impurities through gas-phase purification. During the gas-phase purification, the mass-to-charge ratios of precursor ions within at least a selected range are selectively changed allowing ions having similar unmodified mass-to-charge ratios to be separated before further isolation, fragmentation or analysis.

A method of preparing or operating a mass spectrometer vacuum interface comprising a skimmer apparatus having a skimmer aperture and an internal surface of the skimmer apparatus, comprising disposing an adsorbent or getter material on the internal surface. The internal surface has a deposition region where matter from plasma flows may be deposited and the material is disposed on part or all of the deposition region. The disposing step may be performed before a first use and/or intermittently, especially to refresh a previously disposed material. Providing such material serves to trap or collect deposition matter which might anyway be deposited but in such a way that subsequent liberation of that matter is prevented or at least reduced.

The present invention relates to the field of Alzheimer's disease (AD). More specifically, the present invention provides methods and compositions useful in diagnosing and assessing AD. In another embodiment, a method for diagnosing Alzheimer's Disease (AD) in a patient comprises the steps of (a) obtaining CSF sample from the patient; (b) adding to the sample isotopically labeled peptides identical to a portion of one or more biomarker proteins, wherein the one or more biomarker proteins comprise total APP, APP isoform 751, APP isoform 770, amyloid beta 40 peptide, APOE, and Clusterin; and (c) measuring the one or more biomarker proteins in the sample using mass spectrometry, wherein the level of one or more biomarker proteins compared to a control correlates with AD in the patient.

An apparatus detects a material within a sample and includes signal generation circuitry that generates a first light beam having at least one orbital angular momentum applied thereto and applies the first beam to the sample. The orbital angular momentum imparts a phase factor of exp(im), where m is at least one of an integer value or fractional value and is the azimuth angle, to the first light beam. A detector receives the first light beam after the first light beam passes through the sample and detects the material responsive to a detection of a predetermined phase factor within the first light beam received from the sample.