Patent Description:
In the field of criminal evidence reconnaissance, it is necessary to discover and obtain criminal evidences left by suspects, including fingerprint evidence, palmprint evidence, and trace evidence that can reflect DNA characteristics, thereby constructing an evidence chain of criminal facts and laying a legal evidence basis for punishing crimes.

In the prior art, there were reports on the use of indanedione for developing a handprint, and the inventor had also proposed a method for developing a handprint using indanedione in Chinese Patent <CIT> (application NO. <CIT>), which uses indanedione, glacial acetic acid, ethyl acetate and petroleum ether as raw materials to prepare a fluorescent development reagent, and which can well extract a handprint on a brick, a wooden stick, a fabric and a leather. However, during use, it was found that the fluorescent development reagent used in the method has a strong irritating odor, which is easy to cause discomfort to the operator, and the storage period of the fluorescent development reagent is only <NUM> weeks, which also requires to be stored at <NUM> low temperature, the prepared fluorescent development reagent can only be used within <NUM> weeks, and when more than <NUM> weeks, the fluorescent development reagent may crystallize or produce other variations, and cannot be used, which is easy to cause waste. Further, when the fluorescent development reagent is sprayed, the phenomenon that the precipitated crystals block the nozzle is likely to occur, resulting in uneven spraying.

Levin-elad Michal et al compared the development of fingermarks on used train tickets by three leading reagents for amino acids-ninhydrin, DFO and <NUM>,<NUM>-indanedione. It is found that the superiority of <NUM>,<NUM>-indanedione is demonstrated using both the traditional comparison tests as well as the suggested "PFD" (See "<NPL>.

Chun-Chieh Chen et al determined the optimal components of ninhydrin, <NUM>,<NUM>-illdanedione, <NUM>,<NUM>-diazafluoren-<NUM>-one (DFO), and <NUM>-methylthioninhydrin (<NUM>-MTN) for yielding clear fingerprints on thermal paper by systematically adjusting the relative amounts of the reagents, polar solvents, and the nonpolar diluent petroleum ether, followed by validation on text-printed thermal paper (see "<NPL>).

Bicknell et al found that there exists a direct correlation between the moisture content of the paper on which the prints are deposited and the % RH of the air, such that one can predict the method of processing that will yield the most optimal results based upon these values (see "<NPL>).

The technical problem to be solved by the present invention is to provide a method for developing biological trace evidence on a porous object, and a biological fluorescent development reagent used in this method produces no obvious acid odor, and thus does not cause any unpleasant experience to operator.

The present invention further provides a biological fluorescent development reagent.

To solve the above technical problems, the present invention employs the following technical solution:
a method for developing biological trace evidence on a porous object, comprises immersing a porous object in a biological fluorescent development reagent or spraying a biological fluorescent development reagent on the porous object, drying the porous object in an environment having a relative humidity of less than <NUM>% at a temperature of <NUM> - <NUM>, irradiating the dried porous object with a laser having a wavelength of <NUM> and a full width at half-maximum of less than <NUM>, controlling a surface of the porous object with an illuminance of over <NUM>,<NUM> lux, and using a cut-off filter under <NUM> to develop biological trace evidence on the porous object, and a raw material formulation of the biological fluorescent development reagent is, in percent by weight, <NUM>% - <NUM>% of indanedione, <NUM>% - <NUM>% of ethyl acetate, <NUM>% - <NUM>% of glycerol, <NUM>% - <NUM>% of pure alcohol, and <NUM>% - <NUM>% of petroleum ether.

In some implementations, the biological trace evidence comprises a handprint.

In some implementations, the handprint refers to a fingerprint or a palmprint.

In the present implementations, a cut-off filter under <NUM> refers to a cut-off filter that allows only light waves of or above <NUM> to pass through, while other light waves cannot pass.

The method of the present invention is applicable to various porous objects such as porous objects with high permeability, specifically including napkin, toilet paper, thermal paper, invoice paper, etc.; such as porous objects with moderate permeability, specifically including writing paper, cloth, etc.; such as porous objects with weak permeability, specifically including brick, wood, and stone.

For the porous objects with high permeability, a biological fluorescent development reagent with a relatively low mass concentration of indanedione can be used; for the porous objects with moderate permeability, a biological fluorescent development reagent with a moderate mass concentration of indanedione can be used; for the porous objects with weak permeability, a biological fluorescent development reagent with a relatively high mass concentration of indanedione can be used. However, if the concentration of indanedione is too high, the resulting handprint pattern is easily blurred and cannot be used, and when a low concentration of indanedione is used, a clear handprint pattern is easily generated, and if the concentration is too low, the handprint may also be unclear or cannot be seen.

In a specific implementation, the porous object is a napkin, toilet paper, thermal paper or invoice paper, the raw material formulation of the biological fluorescent development reagent is, in percent by weight, <NUM>% - <NUM>% of indanedione, <NUM>% - <NUM>% of ethyl acetate, <NUM>% - <NUM>% of glycerol, <NUM>% - <NUM>% of pure alcohol, and <NUM>% - <NUM>% of petroleum ether. In a specific implementation, the porous object is a writing paper or cloth, the raw material formulation of the biological fluorescent development reagent is, in percent by weight, <NUM>% - <NUM>% of indanedione, <NUM>% - <NUM>% of ethyl acetate, <NUM>% - <NUM>% of glycerol, <NUM>% - <NUM>% of pure alcohol, and <NUM>% - <NUM>% of petroleum ether.

In a specific implementation, the porous object is a brick, wood or stone, the raw material formulation of the biological fluorescent development reagent is, in percent by weight, <NUM>% - <NUM>% of indanedione, <NUM>% - <NUM>% of ethyl acetate, <NUM>% - <NUM>% of glycerol, <NUM>% - <NUM>% of pure alcohol, and <NUM>% - <NUM>% of petroleum ether.

In the present invention, pure alcohol refers to > <NUM>% absolute ethanol, C<NUM>H<NUM>OH. Preferably, when immersing the porous object in the biological fluorescent development reagent, the immersing time is controlled to be <NUM> -<NUM> sec.

Preferably, before immersing in the biological fluorescent development reagent or spraying the biological fluorescent development reagent, a moisture content of the porous object is controlled to be less than <NUM>%.

More preferably, before immersing in the biological fluorescent development reagent or spraying the biological fluorescent development reagent, the moisture content of the porous object is controlled to be <NUM> - <NUM>%.

Preferably, the porous object is dried in an environment having a relative humidity of less than <NUM>% at a temperature of <NUM> - <NUM>.

The present invention provides another technical solution:
A biological fluorescent development reagent for developing biological trace evidence on a porous object is provided, and a raw material formulation of the biological fluorescent development reagent is, in percent by weight, <NUM>% - <NUM>% of indanedione, <NUM>% - <NUM>% of ethyl acetate, <NUM>% - <NUM>% of glycerol, <NUM>% - <NUM>% of pure alcohol, and <NUM>% - <NUM>% of petroleum ether.

The present invention further provides an alternative technical solution:
a method for developing biological trace evidence on a porous object comprises immersing a porous object in a biological fluorescent development reagent or spraying a biological fluorescent development reagent on the porous object, drying the porous object in an environment having a relative humidity of less than <NUM>% at a temperature of <NUM> - <NUM>, irradiating the dried porous object with a laser having a wavelength of <NUM> and a full width at half-maximum of less than <NUM>, controlling a surface of the porous object with an illuminance of over <NUM>,<NUM> lux, and using a cut-off filter under <NUM> to develop the biological trace evidence on the porous object, a raw material formulation of the biological fluorescent development reagent is indanedione, ethyl acetate, glycerol, pure alcohol and petroleum ether; wherein, in volume ratio, ethyl acetate: glycerol: pure alcohol: petroleum ether = (<NUM> - <NUM>): (<NUM> - <NUM>): (<NUM> - <NUM>): (<NUM> - <NUM>); when preparing, indanedione is dissolved in ethyl acetate at a mass concentration of <NUM> - <NUM>/mL.

In a specific implementation, the porous object is a napkin, toilet paper, thermal paper or invoice paper, the biological fluorescent development reagent is prepared by dissolving indanedione in ethyl acetate at a mass concentration of <NUM> - <NUM>/mL. In a specific implementation, a preferable formulation of the biological fluorescent development reagent is, <NUM> - <NUM> of indanedione; <NUM> - <NUM> of ethyl acetate, <NUM> - <NUM> of glycerol, <NUM>-<NUM> of pure alcohol, and <NUM> - <NUM> of petroleum ether.

In a specific implementation, the porous object is a writing paper or cloth, the biological fluorescent development reagent is prepared by dissolving indanedione in ethyl acetate at a mass concentration of <NUM> - <NUM>/mL. In a specific implementation, a preferable formulation of the biological fluorescent development reagent is, <NUM> - <NUM> of indanedione; <NUM>-<NUM> of ethyl acetate, <NUM> - <NUM> of glycerol, <NUM>-<NUM> of pure alcohol, and <NUM> - <NUM> of petroleum ether.

In a specific implementation, the porous object is a brick, wood or stone, the biological fluorescent development reagent is prepared by dissolving indanedione in ethyl acetate at a mass concentration of <NUM> - <NUM>/mL. In a specific implementation, a preferable formulation of the biological fluorescent development reagent is, <NUM> - <NUM> of indanedione; <NUM>-<NUM> of ethyl acetate, <NUM> - <NUM> of glycerol, <NUM>-<NUM> of pure alcohol, and <NUM> - <NUM> of petroleum ether.

The present invention further provides another alternative technical solution:
A biological fluorescent development reagent for developing biological trace evidence on a porous object, a raw material formulation of the biological fluorescent development reagent is indanedione, ethyl acetate, glycerol, pure alcohol and petroleum ether; wherein, in volume ratio, ethyl acetate: glycerol: pure alcohol: petroleum ether = (<NUM> - <NUM>): (<NUM> - <NUM>): (<NUM> - <NUM>): (<NUM> - <NUM>); when preparing, indanedione is dissolved in ethyl acetate at a mass concentration of <NUM> - <NUM>/mL.

Due to the implementation of the above technical solution, the present invention has the following advantages over the prior art:
The biological fluorescent development reagent used in the present invention produces no obvious acid odor, and thus does not cause any unpleasant experience to operator.

Glycerol is used in the biological fluorescent development reagent used in the method of the present invention, and glycerol has a function of slow volatility, and therefore, when the spraying method is employed, the phenomenon that the precipitated crystals block the nozzle will not occur after spraying a plurality of times (four times or more).

The storage condition of the fluorescent development reagent of the present invention is widened, and the appearance of crystallization will not occur after storage at room temperature (<NUM>) for <NUM> days.

In the following, the present invention is further explained in detail combining with the specific embodiments, but not limited to these embodiments.

This embodiment provides a method for developing a handprint on a porous object, and a formulation of a biological fluorescent development reagent used in this method was: indanedione <NUM>; ethyl acetate <NUM>; glycerol <NUM>; pure alcohol <NUM>; petroleum ether <NUM>.

The developing method comprises the following steps:.

The state of the biological fluorescent development reagent used in the method of this embodiment after <NUM> days of storage is shown in <FIG>, and it was found that there was no crystallization or other variation appeared in the reagent.

The state of the biological fluorescent development reagent used in the method of this embodiment after <NUM> days of storage is shown in <FIG>, and it was found there was no crystallization or other variation appeared in the reagent.

This embodiment provides a method for developing a handprint on a porous object, and the biological fluorescent development reagent used in this embodiment was the same with that used in Embodiment <NUM>.

The state of the biological fluorescent development reagent used in the method of this embodiment after <NUM> days of storage is shown in <FIG>, and it was found that was no crystallization or other variation appeared in the reagent.

This control embodiment provides a method for developing a handprint on a porous object, and a formulation of a biological fluorescent development reagent used in this method was: indanedione <NUM>; ethyl acetate <NUM>; glycerol <NUM>; pure alcohol <NUM>; petroleum ether <NUM>.

This control embodiment provides a method for developing a handprint on a porous object, and the biological fluorescent development reagent used in this control embodiment was the same with that used in Control <NUM>.

Claim 1:
A method for developing biological trace evidence on a porous object, comprising immersing a porous object in a biological fluorescent development reagent or spraying a biological fluorescent development reagent on the porous object, drying the porous object in an environment having a relative humidity of less than <NUM>% at a temperature of <NUM> - <NUM>, irradiating the dried porous object with a laser having a wavelength of <NUM> and a full width at half-maximum of less than <NUM>, controlling a surface of the porous object with an illuminance of over <NUM>,<NUM> lux, and using a cut-off filter under <NUM> to develop the biological trace evidence on the porous object, is characterized in that, a raw material formulation of the biological fluorescent development reagent is, in percent by weight, <NUM>% - <NUM>% of indanedione, <NUM>% - <NUM>% of ethyl acetate, <NUM>% - <NUM>% of glycerol, <NUM>% - <NUM>% of pure alcohol, and <NUM>% - <NUM>% of petroleum ether.