DETAILED ACTION
The amendment filed on 02/18/2026 has been entered and fully considered. Claims 1 and 5-18 are pending, of which claim 1, 5-6 and 8-10 are amended.
Response to Amendment
In response to amendment, the examiner maintains rejection over the prior art established in the previous Office action.
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1 and 5-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (CN 110862305, IDS) (Li).
Regarding claim 1, Li teaches a method for detecting content and fingerprint of monosaccharide in a sample of carob water extract (par [0065]), comprising:
performing detection by using a high-performance liquid chromatography-evaporative light scattering detection method (par [0061]),
wherein the monosaccharide comprises D-glucose anhydrous, D-fructose, sucrose, and pinitol (Fig. 4, par [0067]),
wherein the chromatographic column in the high-performance liquid chromatography-evaporative light scattering detection method is a ZORBAX Carbohydrate column with a specification of 4.6 mm x 250 mm and 5 μm (par [0061]),
wherein the mobile phase in the high-performance liquid chromatography-evaporative light scattering detection method is a gradient solution of acetonitrile and water (par [0061]-[0063]),
wherein a flow rate of the mobile phase in the high-performance liquid chromatography-evaporative light scattering detection method is 0.95-1.05 ml/min, preferably 1 ml/min (par [0061]).
Li does not specifically teach that the sample is Compound Kushen Injection CKI). However, Li discloses a high-performance liquid chromatography–evaporative light scattering detection (HPLC-ELSD) method for detecting monosaccharides including D-pinitol, fructose, glucose, and sucrose. The presently claimed method likewise uses HPLC-ELSD to detect the same types of monosaccharides. The difference between analyzing carob extract and analyzing CKI represents only a difference in the sample source, not a difference in the analytical principle.
A person of ordinary skill in the art would understand that HPLC-ELSD methods for carbohydrate analysis are broadly applicable to various plant-derived matrices and pharmaceutical preparations containing sugars. Applying the known analytical method of Li to another plant-derived or botanical composition containing the same analytes constitutes a predictable use of prior art elements according to their established functions, consistent with KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398 (2007).
Accordingly, the substitution of CKI for the plant extract analyzed in Li would have been obvious to a person of ordinary skill in the art seeking to analyze monosaccharides in another botanical preparation.
Both Prevail Carbo-hydrate ES column recited in the instant claim and ZORBAX Carbohydrate column used by Li are carbohydrate HPLC columns, 4.6 × 250 mm, 5 μm, designed for separation of simple sugars (glucose, fructose, sucrose, pinitol), commonly used interchangeably in ELSD sugar methods. The only difference is the commercial manufacturer (Prevail in the claim versus the column used by Li). Substituting one commercially available carbohydrate column for another of the same dimensions and particle size would have been an obvious design choice because such columns are widely recognized as interchangeable tools for carbohydrate separations.
Similarly, Li already teaches the use of acetonitrile–water gradient elution for separating the relevant sugars. The particular gradient profile recited in the claims represents a routine adjustment of gradient conditions during method development in chromatography. Adjusting gradient composition and timing to achieve desired retention times or resolution is a well-known practice in HPLC method optimization.
Therefore, the claimed column and gradient conditions represent routine analytical parameter selections, not a patentably distinct invention.
Column temperature in HPLC is a well-known variable affecting:
retention time
peak shape
chromatographic resolution
Accordingly, a person of ordinary skill in the art would routinely adjust column temperature to optimize chromatographic separation for a particular sample matrix.
Li already teaches performing HPLC analysis at 35 °C. Adjusting the temperature upward or downward within commonly used chromatographic ranges—including lower temperatures—would have been an obvious matter of routine experimentation to improve resolution between analytes.
It is well known in the art of ELSD sugar analysis that the drift tube temperature is adjusted empirically to achieve complete evaporation of solvent, adequate droplet drying, minimal thermal degradation and stable baseline.
Because Li already teaches the same sugars (pinitol, fructose, glucose, sucrose) and the same detection technique (HPLC-ELSD), one of ordinary skill in the art would have recognized that the drift tube temperature may be increased or decreased, the precise value depends on column conditions, solvent ratio, flow rate, and desired sensitivity. ELSD drift-tube temperatures in the sugar-detection literature commonly range from 40–80 °C, depending on aqueous mobile-phase proportion
Therefore, moving from Li’s 41 °C to applicant’s claimed 59–61 °C constitutes merely routine parameter optimization, without any unexpected results, yielding predictable performance improvements (e.g., better solvent removal under higher aqueous ratio).
Thus, it would have been obvious to one of ordinary skill in the art to optimize the evaporation temperature of the evaporation light detector in the high-performance liquid chromatography-evaporative light scattering detection by routine experimentation.
Nitrogen is the most common carrier gas used in ELSD. Thus, a PHOSITA would inherently choose nitrogen in the absence of any contrary teaching. Li’s ELSD settings assume a standard ELSD configuration; thus, nitrogen is the expected gas.
ELSD gas flow rate is a routine, result-effective parameter. Gas flow rate in ELSD affects aerosol droplet size, nebulization efficiency, signal strength, baseline noise. Thus, it would have been obvious to one of ordinary skill in the art to optimize the flow rate by routine experimentation.
Regarding claim 5, Li teaches that wherein a flow rate of the mobile phase in the high-performance liquid chromatography-evaporative light scattering detection method is 1 ml/min (par [0061]).
Regarding claim 6, it would have been obvious to one of ordinary skill in the art to optimize the column temperature in the high-performance liquid chromatography-evaporative light scattering detection by routine experimentation.
Regarding claim 7, Li teaches that wherein an injection amount in the high-performance liquid chromatography-evaporative light scattering detection method is 10 μ L or 20 μL (par [0065]).
Regarding claim 8, It is well known in the art of ELSD sugar analysis that the drift tube temperature is adjusted empirically to achieve complete evaporation of solvent, adequate droplet drying, minimal thermal degradation and stable baseline.
Because Li already teaches the same sugars (pinitol, fructose, glucose, sucrose) and the same detection technique (HPLC-ELSD), one of ordinary skill in the art would have recognized that the drift tube temperature may be increased or decreased, the precise value depends on column conditions, solvent ratio, flow rate, and desired sensitivity. ELSD drift-tube temperatures in the sugar-detection literature commonly range from 40–80 °C, depending on aqueous mobile-phase proportion
Therefore, moving from Li’s 41 °C to applicant’s claimed 60 °C constitutes merely routine parameter optimization, without any unexpected results, yielding predictable performance improvements (e.g., better solvent removal under higher aqueous ratio).
Thus, it would have been obvious to one of ordinary skill in the art to optimize the evaporation temperature of the evaporation light detector in the high-performance liquid chromatography-evaporative light scattering detection by routine experimentation.
Regarding claim 9, in ELSD operation, the atomizing (nebulization) temperature is a result-effective variable, selected to ensure optimal aerosol formation, governed by solvent volatility, flow rate, and analyte stability.
Because Li performs HPLC-ELSD on aqueous–organic sugar samples, the skilled artisan would understand that atomizer temperature must be adjusted as needed, typical values range from 30–90 °C, and choosing a higher temperature improves droplet formation for aqueous-rich mobile phases.
It would have been obvious to one of ordinary skill in the art to optimize an Atomizing temperature of the evaporation light detector in the high-performance liquid chromatography-evaporative light scattering detection by routine experimentation.
Regarding claim 10, Nitrogen is the most common carrier gas used in ELSD. Thus, a PHOSITA would inherently choose nitrogen in the absence of any contrary teaching. Li’s ELSD settings assume a standard ELSD configuration; thus, nitrogen is the expected gas.
ELSD gas flow rate is a routine, result-effective parameter. Gas flow rate in ELSD affects aerosol droplet size, nebulization efficiency, signal strength, baseline noise. Thus, it would have been obvious to one of ordinary skill in the art to optimize the flow rate by routine experimentation.
Regarding claim 11, in HPLC practice, the blank (injecting solvent with no analyte) must be compatible with the mobile phase, to avoid peak distortion, baseline disturbances, or solvent-front artifacts.
Since Li’s method uses acetonitrile and water exclusively as the mobile phase components, a PHOSITA would automatically prepare the blank from the same solvents.
Choosing 50:50 ACN:H₂O is a routine choice. In carbohydrate analysis, 50:50 acetonitrile–water is one of the most common diluent/blank mixtures because it is miscible with both high-ACN and high-water regions of the gradient, stable toward ELSD nebulization, non-reactive with sugars. Thus, selecting 50:50 is ordinary optimization.
Regarding claim 12, Li teaches weighing the same four reference substances: pinitol, fructose, glucose, sucrose, dissolving them in solvent to prepare reference solutions for HPLC–ELSD detection (par [par [0064]). Use of these reference solutions to identify retention times and quantify sugar content for each analyte (par [0067]). Thus, Li teaches use of multiple reference standards of the same analytes, injected by ELSD for quantification.
A PHOSITA would understand that instead of running four separate reference solutions, it is standard and widely accepted practice to combine multiple analytes into a single mixed reference solution to reduce injection time, minimize solvent use, and improve calibration efficiency. This is a routine laboratory optimization.
Changing the concentration of reference standards is a result-effective variable.
Regarding claim 13, Li teaches taking a sample of the test liquid, diluting to a defined volume, dissolving in mobile-phase compatible solvent, filtering, using the filtrate as the test solution for HPLC–ELSD (par [0065]).
This is the same type of routine sample-prep step recited in Claim 13.
CKI is itself a liquid injection containing the analytes of interest (sugars). To run HPLC–ELSD, an aliquot must be taken, diluted to fall inside the detector’s linear range, filtered to remove particulates.
Li performs the same actions for its sample (carob extract liquid).
A PHOSITA analyzing CKI with the HPLC–ELSD method taught by Li would be motivated to dilute the CKI sample to appropriate levels for ELSD calibration, use the same solvent system (ACN/H₂O) to maintain solvent compatibility, filter the sample to protect the column and stabilize the baseline. This is exactly the same reasoning Li uses for its test solution preparation in par [0065].
Claim recited volumes (1 mL → 20 mL) and the use of CKI rather than carob extract are routine, non-critical, predictable modifications.
Regarding claim 14, Li teaches the same detector (ELSD) (par [0061]), the same four analytes (par [0064]), the same class of carbohydrate columns with identical dimensions (par [0061]), the same solvent system (ACN/H₂O) (par [0061]), similar ELSD tuning parameters (par [0061]), the same sample and standard preparation steps (par [0065]), and the same quantitation method (par [0067]).
The Table in Claim 14 merely provides routine, result-effective method parameters that a PHOSITA would predictably select when applying Li’s method to Compound Kushen Injection.
Regarding claim 15, Li teaches that the method comprises constructing a fingerprint of the sample containing D-glucose anhydrous, D-fructose, sucrose, and pinitol (par [0067][0068]).
Thus, simply substituting CKI into an already-known ELSD sugar fingerprinting method is obvious.
Regarding claim 16, the claim merely specifies routine, predictable HPLC–ELSD conditions for performing the same analysis already disclosed by Li.
Li provides same analyzer (ELSD) (par [0061]), same solvent system (par [0061]), same chromatographic hardware (par [0061]), same analytes (par [0064]), same sample-prep steps (par 0065]), same quantitation method (par [0067]).
The Table of parameters in Claim 16 contains only result-effective variables, all of which would have been obvious to optimize.
Regarding claim 17, Li teaches that wherein the standard fingerprint comprises a D-fructose chromatographic peak, a pinitol chromatographic peak, a D-glucose anhydrous chromatographic peak, and a sucrose chromatographic peak plus multiple additional peak (Fig. 1).
Running HPLC–ELSD on a complex botanical extract (such as Li’s carob extract) always produces target peaks (known sugars), and non-target peaks (unknowns). This is the definition of a chromatographic fingerprint.
A PHOSITA would expect CKI to contain sugars, amino acids, organic acids, alkaloids, matrix polysaccharides, trace excipients. HPLC–ELSD of CKI will naturally generate multiple additional peaks beyond simple sugars. Thus, the presence of three unknown peaks is not only obvious—it is expected.
Regarding claim 18, the claim’s relative retention time (RRT) ranges fall within the expected variation created by different columns (ZORBAX vs Prevail), different temperatures (Li uses 35 °C; claim uses 15 °C), different ACN gradients, slight shifts in peak elution under ELSD.
A PHOSITA routinely expects 10–20% drift in retention time between instruments and expresses this number as an RRT range.
Response to Arguments
Applicant's arguments filed 02/18/2026 have been fully considered but they are not persuasive.
Applicant argues that Li discloses analysis of carob pod water extract, whereas the claimed invention analyzes Compound Kushen Injection (CKI), which Applicant characterizes as a “distinct and complex pharmaceutical composition.”
This argument is not persuasive.
Li discloses a high-performance liquid chromatography–evaporative light scattering detection (HPLC-ELSD) method for detecting monosaccharides including D-pinitol, fructose, glucose, and sucrose. The presently claimed method likewise uses HPLC-ELSD to detect the same types of monosaccharides. The difference between analyzing carob extract and analyzing CKI represents only a difference in the sample source, not a difference in the analytical principle.
A person of ordinary skill in the art would understand that HPLC-ELSD methods for carbohydrate analysis are broadly applicable to various plant-derived matrices and pharmaceutical preparations containing sugars. Applying the known analytical method of Li to another plant-derived or botanical composition containing the same analytes constitutes a predictable use of prior art elements according to their established functions, consistent with KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398 (2007).
Accordingly, the substitution of CKI for the plant extract analyzed in Li would have been obvious to a person of ordinary skill in the art seeking to analyze monosaccharides in another botanical preparation.
Applicant argues that the claimed invention uses a Prevail Carbo-hydrate ES column and a specific gradient program, which allegedly are not disclosed by Li.
This argument is also not persuasive.
Li teaches the use of a carbohydrate-analysis HPLC column having dimensions 4.6 mm × 250 mm with 5 µm particles. The presently claimed column has the same dimensions and particle size and is likewise a carbohydrate-analysis column. The only difference is the commercial manufacturer (Prevail versus the column used by Li). Substituting one commercially available carbohydrate column for another of the same dimensions and particle size would have been an obvious design choice because such columns are widely recognized as interchangeable tools for carbohydrate separations.
Similarly, Li already teaches the use of acetonitrile–water gradient elution for separating the relevant sugars. The particular gradient profile recited in the claims represents a routine adjustment of gradient conditions during method development in chromatography. Adjusting gradient composition and timing to achieve desired retention times or resolution is a well-known practice in HPLC method optimization.
Therefore, the claimed column and gradient conditions represent routine analytical parameter selections, not a patentably distinct invention.
Applicant asserts that under Li’s chromatographic conditions, fructose and pinitol co-elute, and that the claimed method achieves improved separation by using lower column temperatures.
This argument is not persuasive.
First, Li expressly identifies chromatographic peaks corresponding to the sugars being analyzed, including pinitol and fructose, demonstrating that Li’s method is capable of detecting those analytes.
Second, even assuming that Li’s original chromatographic parameters did not provide optimal separation, it is well known in the art that chromatographic resolution can be adjusted by modifying routine parameters such as temperature, mobile-phase composition, gradient slope, and flow rate. Thus, a person of ordinary skill in the art would reasonably expect that separation between peaks could be improved by routine experimentation adjusting these parameters, including column temperature.
Such optimization of chromatographic parameters is considered routine method development, which does not render the resulting conditions non-obvious.
Applicant further argues that Li processes the sample under acidic conditions (pH 4–5) whereas the claimed method allegedly process under neutral or slightly alkaline conditions and therefore the methods are not comparable.
This argument is not persuasive.
The presently pending claims do not recite any limitation regarding pH conditions for analysis or sample preparation. Patentability must be evaluated based on the limitations actually recited in the claims. See In re Self, 671 F.2d 1344, 1348 (CCPA 1982) (“limitations not appearing in the claims cannot be relied upon for patentability”).
Because the claims contain no pH limitation, differences in pH between Li’s disclosure and Applicant’s described experimental conditions are not relevant to the patentability analysis. Even if Li performs a pretreatment step at pH 4–5, this does not distinguish the claimed method since the claims do not require any particular pH condition.
Furthermore, the claims are directed to a chromatographic detection method using HPLC-ELSD, and Applicant has not demonstrated that the alleged pH differences would prevent the method of Li from being applied to the claimed analysis.
Accordingly, the argument regarding pH does not overcome the rejection under 35 U.S.C. §103.
Applicant further argues that selecting a column temperature of 13–20 °C would not have been obvious and cites In re Stepan Co. in support of this position.
The Examiner does not agree.
The cited case does not preclude a finding of obviousness when the claimed range results from routine optimization of a result-effective variable. Column temperature in HPLC is a well-known variable affecting:
retention time
peak shape
chromatographic resolution
Accordingly, a person of ordinary skill in the art would routinely adjust column temperature to optimize chromatographic separation for a particular sample matrix.
Li already teaches performing HPLC analysis at 35 °C. Adjusting the temperature upward or downward within commonly used chromatographic ranges—including lower temperatures—would have been an obvious matter of routine experimentation to improve resolution between analytes.
Applicant has not provided evidence demonstrating that the claimed temperature range yields unexpected results or a critical effect beyond what would normally be expected from temperature adjustments in chromatography.
Therefore, the argument based on In re Stepan is not persuasive.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to XIAOYUN R XU, Ph. D. whose telephone number is (571)270-5560. The examiner can normally be reached M-F 8am-5pm.
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/XIAOYUN R XU, Ph.D./Primary Examiner, Art Unit 1797