JP2014052322A - Analysis method of physiologically active substance contained in hair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To analyze a component of hair quantitatively and continuously.SOLUTION: An analysis method of physiologically active substance accumulated in hair includes the following steps: step 1 of slicing hair in a major axis direction and exposing medulla; step 2 of applying internal standard substance to the surface exposed at step 1; and step 3: of performing imaging mass spectrometry (IMS) on the surface obtained at step 2, and detecting a physiologically active substance in hair continuously and quantitatively.

Description

  The present invention relates to an imaging technique for physiologically active substances in hair.

  Conventionally, measurement of drugs, luxury products, etc. in hair has been quantitatively measured with a chromatography / mass spectrometer after extracting and concentrating the target substance from several tens of hairs. However, the measurement result was a discontinuous / average value for a certain period, and the possibility of external contamination / passive intake could not be completely avoided.

  Patent document 1 describes the method of analyzing the physiologically active substance in hair by solvent-extracting hair.

  Non-Patent Document 1 describes a barcode-like analysis of methamphetamine in hair.

  Non-Patent Document 2 describes the analysis of cocaine in hair.

JP2008-232674

J. Mass Spectrometry, 46, 411-416, 2011. Anal.Chem., 83 (11): 4266-72, 2011

  Patent Document 1 can only analyze discontinuous and qualitative chemical substances.

  According to Non-Patent Documents 1 and 2, barcode-like analysis of methamphetamine, cocaine, and the like in hair is possible, but quantitative analysis is not possible, so that it is insufficient as evidence of illegal drug use.

  An object of this invention is to provide the analysis technique which can specify the use time and the usage-amount of the physiologically active substance in hair.

The present invention provides the following hair analysis method.
Item 1. A method for analyzing physiologically active substances accumulated in hair, comprising the following steps: Step 1: slicing hair in the long axis direction to expose medulla Step 2: Internal standard substance on the surface exposed in Step 1 Applying Step 3: Performing imaging mass spectrometry (IMS) on the surface obtained in Step 2, and continuously and quantitatively detecting the physiologically active substance in the hair. Analysis method of accumulated physiologically active substance.
Item 2. Item 2. The analysis method according to Item 1, wherein the physiologically active substance is an illegal drug.
Item 3. Item 3. The analysis method according to Item 1 or 2, wherein the IMS is performed using MALDI-TOFMS.
Item 4. Item 4. The analysis method according to any one of Items 1 to 3, wherein the hair is sliced by a microtome.
Item 5. Item 5. The analysis method according to any one of Items 1 to 4, wherein the hair slice in Step 1 is performed on the frozen and fixed hair.
Item 6. Item 6. The analysis method according to any one of Items 1 to 5, wherein the IMS is a scanning IMS.

  According to the present invention, since a physiologically active substance in hair can be analyzed by slicing hair in the long axis direction using a device such as a microtome, the preparation of a hair sample is quick and reproducibility is good. The properties of hair such as gray hair, dyed hair, comb hair, length, and thickness are irrelevant to the analysis of physiologically active substances, and are not affected by surface contaminants.

  The spatial resolution of the hair is about 50 μm, which corresponds to a 2-3 hour growth of the hair. In other words, continuous analysis of physiologically active substances can be performed in units of 2 to 3 hours, and the use history of illegal drugs such as narcotics and stimulants can be accurately reflected, and there is sufficient evidence capacity in trials. .

  The physiologically active substances analyzed in the present invention are not limited to chemical substances taken from outside the body such as illegal drugs, pharmaceuticals, and luxury products (nicotine, etc.), but include in vivo proteins / peptides / lipids / nucleic acids, etc. It is possible to widely analyze physiologically active substances that can accumulate in

Quantitative mass barcode imaging (QMBI) of nicotine (NC) on the hair surface prepared by a rotating microtome system ^TM equipped with a freezing unit Electron microscope of intact hair, manual scratch and mechanically sliced hair Photo Quantitative Mass Barcode Imaging (QMBI) of Nicotine (NC) on Hair Surface Prepared by Rotating Microtome System ^TM with Freezing Unit NC and NC- ^13C ₃ MALDI-TOF Mass Spectra in SRM Mode Quantitative mass barcode-like imaging (QMBI) of nicotine (NC) on the hair surface prepared by a rotating microtome system ^TM equipped with a freezing unit. Calibration curve with NC content from 1 ng / mL to 50 ng / mL. In triple measurement (▲, ■, ◆), the average value means "X". Quantitative mass barcode-like imaging (QMBI) of nicotine (NC) on the hair surface prepared by a rotating microtome system ^TM equipped with a freezing unit QIMS of NC slices of a 2 cm long slice of heavy smoker and NC MALDI-TOF mass spectrum. The colored heat map of the QIMS image shows the traceability of the NC content with a spatial resolution of every 50 μm. Colored heat map of QIMS image of NC content of sliced hair sample Colored heat map of QIMS image in length sliced hair from 7 regular heavy smokers and 3 non-smokers Colored heat map of QIMS images of NC content of sliced hair samples Comparison of QIMS images between QIMS images of three slices of hair smoker and intact hair (HS-3, 8 and 10) ) Comparison with three treatment methods (untreated, peeling method with sponge abrasive, ultra-thin cutting method with microtome)

  The present invention enables continuous tracking of physiologically active substances present and accumulated in hair by using an ultra-thin cut surface of hair as a sample and combining mass imaging (IMS) as a means.

  Hair has a cortex area around the medulla and a cuticle area on the outermost layer. In the method of the present invention, the hair slices the cuticle region and cortex region in the longitudinal direction until the medulla is exposed. Before this operation, a washing process for washing the contaminants attached to the hair surface may be performed. However, since the contaminants attached to the hair surface are removed at the same time when slicing the hair surface, the hair is removed. It is not always necessary to perform the washing operation.

  The long-axis slicing step of hair can be performed using a microtome. Examples of the microtome include a microtome equipped with a glass knife. The apparatus for slicing hair is not limited to a microtome, and any apparatus that can slice hair very thinly can be used. In the present invention, since the physiologically active substance in the hair is analyzed continuously and quantitatively, it is preferable that the slicing is performed with high accuracy and the medullary portion of the hair is uniformly exposed on the slice surface.

  The hair slicing operation is preferably performed by fixing the frozen hair to a microtome or the like. When a microtome is used after embedding hair in paraffin or the like, peaks of paraffin or the like appear strongly during IMS, making it difficult to quantify the target substance.

Next, a solution containing a labeled internal standard substance is applied to the hair from which the medulla (medulla) is exposed by spraying or the like, and then imaging mass spectrometry (IMS) is performed. The IMS is preferably a scanning type IMS. The internal standard substance can be labeled preferably with ¹³ C, but an internal standard substance labeled with other stable isotopes such as ¹⁵ N and ¹⁷ O may be used. The labeled internal standard is preferably applied to the hair sliced with the matrix when using a matrix-assisted laser ionization method such as MALDI.

  The target substance can be quantified by determining the ratio of the target substance in the hair to the labeled target substance by IMS.

  It takes 2-3 hours for hair to grow 50 μm, and it is possible to analyze the history of the use of physiologically active substances for 40 to 60 hours at 1 mm and 800 to 1200 hours (about 33 to 50 days) at 20 mm. It is possible to verify the usage history of luxury products / pharmaceuticals. Any physiologically active substance that migrates and accumulates in the hair can be quantified continuously / over time. As a result, it is possible to analyze how much and for how long the disease-causing / related molecule has existed in the living body.

  Human hair is most preferable as a sample used in the present invention, but hair other than head hair (pubic hair, armpit hair, eyelashes, eyebrows, eyelashes, etc.) and animal hair such as cows, horses, dogs, cats, mice, rats, etc. Included in “hair”. The present invention can sufficiently quantitate and continuously analyze a physiologically active substance in hair with a single hair.

  Substances in hair that can be analyzed according to the present invention are not particularly limited, for example, stimulants, narcotics, psychotropic drugs, illegal drugs, sports doping controlled drugs, or other drugs, particularly legally controlled drugs or metabolites thereof, Protein (enzyme, hormone, receptor, cytokine, etc.), peptide (hormone, etc.), lipid (neutral fat, wax, ceramide, phospholipid, sphingophospholipid, glycerophospholipid, sphingoglycolipid, glyceroglycolipid, lipoprotein, Sulfolipids, terpenoids, steroids and the like) are exemplified. Moreover, agricultural chemicals, animal and plant toxicants, environmental pollutants, harmful elements, radioactive substances, and other harmful substances and toxic substances are also exemplified. More specifically, for example, stimulants methamphetamine and amphetamine, narcotics MDMA, MDA, morphine, cocaine and heroin, cannabis components THC, pharmaceuticals triazolam and diazepam, sports doping-inhibiting drugs testosterone, Ethyl glucuronide as an indicator of methanol intake, pesticides mesomil, MEP and paraquat, animal and plant toxins tetrodotoxin and aconitine, environmental pollutants dioxin, PCB and benzene, harmful elements arsenic, mercury, lead and thallium, chemical Examples include weapons, radioactive substances, other toxic substances such as nicotine, and metabolites thereof.

Hereinafter, the present invention will be described in more detail with reference to examples.
Example 1
(1) Washing the hair surface Put the hair (about 2cm) into a test tube with a stopper,
1) After ultrasonic cleaning in 0.5% SDS solution for 1 minute, aspirate SDS solution
2) After ultrasonic cleaning for 1 minute in purified water, aspirate purified water
3) After ultrasonic cleaning with methanol for 1 minute, aspirate methanol
4) Repeat 2) → 3) twice
5) Remove the washed hair from the test tube and dry on the Kimwipe

(2) Hair treatment method
1) Peeling method using sponge abrasive (conventional method)
* Fix both ends of the washed hair, and scrape the surface cuticle with a sponge abrasive (Sumitomo 3M Co., Ltd .: Superfine # 1500) while observing under a stereomicroscope (about 25 times).
* Finish when the spinal cord is visible under the microscope, and lightly wipe off the dust on the surface with moistened absorbent cotton.
* Attach conductive double-sided tape (Nitto Denko Corporation: No.5601) to ITO glass slide (Bruker Daltonics: 237001), and fix the hair firmly so that the rubbing surface is on top for IMS analysis. Provide.
2) Ultra-thin cutting method by microtome (invention method)
* Washed hair is affixed to a conductive double-sided tape (Nitto Denko Corporation: No.5601), fixed to a glass slide, and frozen using a biological sample freezing unit (Japan Microtome Research Laboratories) ° C).
* Attach a biological sample freezing unit with a manual microtome system with a stereomicroscope (Japan Microtome Research Laboratories Co., Ltd.).
* End when the spinal cord appears while observing with a stereomicroscope. Assuming that the average human hair diameter is 100 μm, 25 cycles (2 μm × 25 = 50 μm) may be used.
* After completion, return the biological sample freezing unit to room temperature, gently wipe off the water droplets on the conductive double-sided tape, and then remove the glass slide from the unit.
* Carefully remove the conductive double-sided tape on the glass slide, transfer it to an ITO glass slide, and use it for IMS analysis.

(3) Hair cross section scanning quantitative mass imaging analysis method
1) MALDI-TOFMS equipment Equipment used: Autoflex speed (Bruker Daltonics smart beamII)
SRM quantitative analysis: Monitor ion is Parent ion: 163.2> Fragment ion: 132.2
NC is monitored at m / z = 132.2, ¹³ C ₃ -NC is monitored at m / z = 135.2, and quantified from the peak height ratio of 132.2 / 135.2.
2) Matrix α-Cyano-4-hydroxybenzoic acid (CHCA: SIGMA c2020, Lot No: MKBH1245V) was adjusted to 0.2 mg trifluoroacetic acid / 50% acetonitrile solvent to 7 mg / mL, and ImagePrep ^TM (Bruker Daltonics) To the hair cross section.
3) Internal standard substance
A methanol solution of ¹³ C ₃ -NC (CIL: CLM-3914-0.1) is diluted, added to the CHCA solution at a final concentration of 50 ng / mL, and sprayed onto the hair cross section with the matrix.
4) ImagePrep operation
Spraying operation was performed with the file “HCCA_nsh05” specified by Bruker Daltonics.
5) Quantitative calculation Calculate the “pg / mg hair” value from the peak height ratio of 1 cm long hair (= 0.04 mm ³ ) Formula = (132/135) x 25 x 50

(4) Results
1) Reproducibility of NC value by this method (long-term smoker hair:> 30 / day,> 20 years)
9.5 +/- 1.2 ng / mg Hair
34.5 +/- 2.8 ng / mg Hair CV = around 10%
2) Comparison with conventional method: Non-smoker's hair with NC solution (0.1, 1.0 μg / mL) This method: 0.22, 0.36 ng / mg (Conventional method: 0.21 ng / mg)
0.60, 1.13 ng / mg (conventional method: 0.97 ng / mg)
3) Comparison of 3 treatment methods (untreated, exfoliation method with sponge abrasive, ultra-thin cutting method with microtome) (Figure 3) Sample hair: Hair with NC added at 1.0μg / mL Untreated method: 0.23 ng / mg
Peeling method: 0.58 ng / mg
Ultra-thin cutting method: 1.13 ng / mg
The results are shown in Table 1 and FIGS.

Table I. NC content (ng / mg hair) in hair samples sliced along the length of 15 heavy smokers and 7 non-smokers

(5) Discussion This time, we developed a new hair cross-sectional scanning quantitative imaging analysis method using labeled stable isotope as an internal standard and applied it to the determination of nicotine (NC) in smoker hair. In this method, the cuticle layer on the hair surface is peeled off with a microtome with a glass knife, and the hair cross section (ultra thin slice) is continuously scanned using the MS ions (m / z = 163/132) peculiar to NC as an index. NC value can be continuously tracked every hour / month, and labeled stable isotope ( ¹³ C ₃ -NC: m / z = 166/135) is used as an internal standard, enabling highly accurate and sensitive quantitative measurement. became.

  This method has a wide range of applications from non-biomolecules to biomolecules such as proteins, peptides, carbohydrates, and lipids in addition to NC, such as pharmaceuticals, luxury products, supplements, and cosmetics. Is also applicable.

Claims (6)

A method for analyzing physiologically active substances accumulated in hair, comprising the following steps: Step 1: slicing hair in the long axis direction to expose medulla Step 2: Internal standard substance on the surface exposed in Step 1 Applying Step 3: Performing imaging mass spectrometry (IMS) on the surface obtained in Step 2, and continuously and quantitatively detecting the physiologically active substance in the hair. Analysis method of accumulated physiologically active substance. The analysis method according to claim 1, wherein the physiologically active substance is an illegal drug. The analysis method according to claim 1 or 2, wherein IMS is performed using MALDI-TOFMS. The analysis method according to any one of claims 1 to 3, wherein the hair is sliced in step 1 by a microtome. The analysis method according to claim 1, wherein the hair slice in step 1 is performed on frozen and fixed hair. The analysis method according to claim 1, wherein the IMS is a scanning type IMS.